[Federal Register: August 25, 2005 (Volume 70, Number 164)]
[Rules and Regulations]               
[Page 49977-50073]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr25au05-12]                         


[[Page 49977]]

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Part II





Department of Transportation





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Federal Motor Carrier Safety Administration



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49 CFR Parts 385, 390, and 395



Hours of Service of Drivers; Final Rule


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DEPARTMENT OF TRANSPORTATION

Federal Motor Carrier Safety Administration

49 CFR Parts 385, 390 and 395

[Docket No. FMCSA-2004-19608; formerly FMCSA-1997-2350]
RIN-2126-AA90

 
Hours of Service of Drivers

AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT.

ACTION: Final rule.

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SUMMARY: FMCSA is publishing today its final rule governing hours of 
service for commercial motor vehicle drivers, following its Notice of 
Proposed Rulemaking published January 24, 2005. The rule addresses 
requirements for driving, duty, and off-duty time; a recovery period, 
sleeper berth, and new requirements for short-haul drivers. The hours-
of-service regulations published on April 28, 2003, were vacated by the 
U.S. Court of Appeals for the District of Columbia Circuit on July 16, 
2004. Congress subsequently provided, through the Surface 
Transportation Extension Act of 2004, that the 2003 regulations will 
remain in effect until the effective date of a new final rule 
addressing the issues raised by the court or September 30, 2005, 
whichever occurs first. Today's rule meets that requirement.

DATES: This rule is effective October 1, 2005.

FOR FURTHER INFORMATION CONTACT: Tom Yager, Chief, Driver and Carrier 
Operations Division, Office of Bus and Truck Standards and Operations 
(MC-PSD), Federal Motor Carrier Safety Administration, 400 Seventh 
Street. S.W., Washington, DC 20590. Phone 202-366-4009, E-mail 
MCPSD@fmcsa.dot.gov.


SUPPLEMENTARY INFORMATION:

Table of Contents

A. Legal Basis for the Rulemaking
B. Background Information
C. Executive Summary
D. Research Review Process
E. Driver Health
F. Driver Fatigue
G. Current and Future FMCSA Research
H. Crash Data
I. Operational Data
J. Comments to Docket and FMCSA Responses
    J.1. Sleep Loss
    J.2. Exposure to Environmental Stressors
    J.3. Workplace Injuries and Fatalities
    J.4. Lifestyle Choices
    J.5. Driving Time
    J.6. Duty Tour
    J.7. Off-Duty Time
    J.8. The 34-Hour Restart and 60/70-Hour Rules
    J.9. Sleeper-Berth Use
    J.10. Regulation of Short-Haul Operations
    J.11. Combined Effects
    J.12. Effective and Implementation Dates
    J.13. Electronic On-Board Recording Devices
    J.14. Other Provisions
    J.15. Legal Issues
K. Rulemaking Analyses and Notices
    K.1. Executive Order 12866 (Regulatory Planning and Review) and 
DOT Regulatory Policies and Procedures
    K.2. Regulatory Flexibility Act
    K.3. Unfunded Mandates Reform Act of 1995
    K.4. National Environmental Policy Act
    K.5. Paperwork Reduction Act
    K.6. Executive Order 13211 (Energy Supply, Distribution, or Use)
    K.7. Executive Order 12898 (Environmental Justice)
    K.8. Executive Order 13045 (Protection of Children)
    K.9. Executive Order 12988 (Civil Justice Reform)
    K.10. Executive Order 12630 (Taking of Private Property)
    K.11. Executive Order 13132 (Federalism)
    K.12. Executive Order 12372 (Intergovernmental Review)
L. List of References

Table of Abbreviations

AHAS Advocates for Highway and Auto Safety
AMI Acute Myocardial Infarction
AMSA American Moving and Storage Association
ANPRM Advance Notice of Proposed Rulemaking
APA Administrative Procedure Act
ATA American Trucking Associations
BAC Blood Alcohol Content
BLS U.S. Bureau of Labor Statistics
BMI Body Mass Index
CATF Clean Air Task Force
CDL Commercial Drivers License
CEQ Council on Environmental Quality
CFR Code of Federal Regulations
CHP California Highway Patrol
CMV Commercial Motor Vehicle
CRASH Citizens for Reliable and Safe Highways
CRMCA Colorado Ready Mixed Concrete Association
CTC Corporate Transportation Coalition
CVD Cardiovascular Disease
CVSA Commercial Vehicle Safety Alliance
dBA Decibels Adjusted
DE Diesel Exhaust
DOT Department of Transportation
EA Environmental Assessment
ECMT European Conference of Ministers of Transport
EEI Edison Electric Institute
EOBR Electronic On-Board Recorder
EPA U.S. Environmental Protection Agency
FARS Fatality Analysis Reporting System
FHWA Federal Highway Administration
FMCSA Federal Motor Carrier Safety Administration
FMCSR Federal Motor Carrier Safety Regulations
FMP Fatigue Management Program
FONSI Finding of No Significant Impact
FR Federal Register
GVWR Gross Vehicle Weight Rating
HEI Health Effects Institute
HOS Hours of Service
IBT International Brotherhood of Teamsters
ICC Interstate Commerce Commission
ICCTA ICC Termination Act of 1995
IIHS Insurance Institute for Highway Safety
IRP International Registration Plan
ISO International Standards Organization
LBP Lower Back Pain
LH Long Haul
LR Long Regional
LTL Less-Than-Truckload
MCMIS Motor Carrier Management Information System
MCSAP Motor Carrier Safety Assistance Program
MFCA Motor Freight Carriers Association
MPH Miles per Hour
MTA Minnesota Trucking Association
NACA National Armored Car Association
NAICS North American Industrial Classification System
NEPA National Environmental Policy Act
NHTSA National Highway Traffic Safety Administration
NIH National Institutes of Health
NIOSH National Institute for Occupational Safety and Health
NITL National Industrial Transportation League
NPRM Notice of Proposed Rulemaking
NPTC National Private Truck Council
NRMCA National Ready Mixed Concrete Association
NSSGA National Stone, Sand, and Gravel Association
NTSB National Transportation Safety Board
OMB Office of Management and Budget
OOIDA Owner-Operator Independent Drivers Association
OOS Out-of -Service
OSHA U.S. Occupational Safety and Health Administration
OTR Over-the-Road
PATT Parents Against Tired Truckers
PM Particulate Matter
PMC PubMed Central
PRA Paperwork Reduction Act of 1995
PVT Psychomotor Vigilance Test
RIA Regulatory Impact Analysis
RMA Risk Management Association
R&T Research and Technology
RODS Records of Duty Status
SBA Small Business Administration
SH Short Haul
SR Short Regional
STAA Surface Transportation Assistance Act
TCA Truckload Carriers Association
TIFA Trucks Involved in Fatal Accidents
TL Truckload
TOT Time-on-Task
TRB Transportation Research Board
UMTRI University of Michigan Transportation Research Institute
UPS United Parcel Service
USV Utility Service Vehicle
VIUS Vehicle Inventory and Use Survey
VMT Vehicle Miles Traveled
VSL Value of a Statistical Life
VTTI Virginia Tech Transportation Institute
WBV Whole Body Vibration

[[Page 49979]]

A. Legal Basis for the Rulemaking

    This rule is based on the authority of the Motor Carrier Act of 
1935 and the Motor Carrier Safety Act of 1984.
    The Motor Carrier Act of 1935 provides that ``The Secretary of 
Transportation may prescribe requirements for--(1) qualifications and 
maximum hours of service of employees of, and safety of operation and 
equipment of, a motor carrier; and (2) qualifications and maximum hours 
of service of employees of, and standards of equipment of, a motor 
private carrier, when needed to promote safety of operation'' [49 
U.S.C. 31502(b)].
    The hours-of-service regulations adopted today deal directly with 
the ``maximum hours of service of employees of * * * a motor carrier 
[49 U.S.C. 31502(b)(1)] and the ``maximum hours of service of employees 
of * * * a motor private carrier'' [49 U.S.C. 31502(b)(2)]. The 
adoption and enforcement of such rules was specifically authorized by 
the Motor Carrier Act of 1935. This rule rests squarely on that 
authority.
    The Motor Carrier Safety Act of 1984 provides concurrent authority 
to regulate drivers, motor carriers, and vehicle equipment. It requires 
the Secretary of Transportation to ``prescribe regulations on 
commercial motor vehicle safety. The regulations shall prescribe 
minimum safety standards for commercial motor vehicles.'' Although this 
authority is very broad, the Act also includes specific requirements: 
``At a minimum, the regulations shall ensure that--(1) Commercial motor 
vehicles are maintained, equipped, loaded, and operated safely; (2) the 
responsibilities imposed on operators of commercial motor vehicles do 
not impair their ability to operate the vehicles safely; (3) the 
physical condition of operators of commercial motor vehicles is 
adequate to enable them to operate the vehicles safely; and (4) the 
operation of commercial motor vehicles does not have a deleterious 
effect on the physical condition of the operators'' [49 U.S.C. 
31136(a)].
    This rule is based on the authority of the 1984 Act and addresses 
the specific mandates of 49 U.S.C. 31136(a)(2), (3), and (4). Section 
31136(a)(1) of 49 U.S.C. deals almost entirely with the mechanical 
condition of commercial motor vehicles (CMVs), a subject not included 
in this rulemaking. The phrase ``operated safely'' in paragraph (a)(1) 
refers primarily to the safe operation of the vehicle's equipment, but 
to the extent it encompasses safe driving, this rule also addresses 
that mandate.
    Before prescribing any regulations, FMCSA must also consider their 
``costs and benefits'' [49 U.S.C. 31136(c)(2)(A) and 31502(d)]. Those 
factors are also discussed later.

B. Background Information

B.1. History of the Hours-of-Service Rule

    The Interstate Commerce Commission (ICC) promulgated the first 
Federal hours-of-service regulations (HOS) in the late 1930s. The rules 
were based on the Motor Carrier Act of 1935. The regulations remained 
largely unchanged from 1940 until 2003, except for an important 
amendment in 1962. Prior to 1962, driver hours-of-service regulations 
were based on a 24-hour period from noon to noon or midnight to 
midnight. A driver could be on duty no more than 15 hours in a 24-
consecutive-hour period. In 1962, among other rule changes, the 24-hour 
cycle was removed and replaced by minimum off-duty periods. A driver 
could ``restart'' the calculation of his or her driving and on-duty 
limitations after any period of 8 or more hours off duty.
    Section 408 of the ICC Termination Act of 1995 (ICCTA) (Pub. L. 
104-88, 109 Stat. 803, at 958) required the Federal Highway 
Administration (FHWA) to conduct rulemaking ``dealing with a variety of 
fatigue-related issues pertaining to commercial motor vehicle safety.'' 
In response, FHWA published an advance notice of proposed rulemaking 
(ANPRM) on November 5, 1996 (61 FR 57252). FMCSA was established as a 
separate Agency on January 1, 2000. At that time, responsibility to 
promulgate CMV regulations was transferred from FHWA to FMCSA, which 
published an hours-of-service Notice of Proposed Rulemaking (NPRM) on 
May 2, 2000 (65 FR 25540) and a final rule on April 28, 2003 (68 FR 
22456). Technical amendments to the final rule were published on 
September 30, 2003 (68 FR 56208). Motor carriers and drivers were 
required to comply with the final rule on January 4, 2004.
    FMCSA's 2003 rule did not change any hours-of-service requirements 
for motor carriers and drivers operating passenger-carrying vehicles. 
They were required to continue complying with the hours-of-service 
rules existing before the 2003 rule (see 68 FR 22461-22462). Changes in 
hours-of-service provisions in the new rule applied only to motor 
carriers and drivers operating property-carrying vehicles. Compared to 
the previous regulations, the 2003 rule: (1) Required drivers to take 
10, instead of 8, consecutive hours off-duty (except when using sleeper 
berths); (2) retained the prior prohibition on driving after 60 hours 
on duty in 7 days or 70 hours in 8 days; (3) increased allowable 
driving time from 10 to 11 hours in any one duty period; and (4) 
replaced the so-called 15-hour rule (which prohibited drivers from 
driving after being on duty more than 15 hours, not including 
intervening off-duty time) with a 14-hour rule (which prohibited 
driving after the 14th hour after the driver came on duty, with no 
extensions for off-duty time). Note that the 15-hour limit had been 
cumulative--so it could be interspersed with off-duty time--while the 
non-extendable 14-hour limit was consecutive. Additionally, FMCSA 
allowed drivers to ``restart'' the calculations for the 60- and 70-hour 
limits by taking 34 consecutive hours off duty. Based on the data and 
research available at the time, FMCSA was convinced that these new 
rules constituted a significant improvement in the hours-of-service 
regulations, compared to the rules they replaced, by providing drivers 
with better opportunities to obtain off-duty time offering daily 
restorative sleep, thereby reducing the incidence of crashes wholly or 
partially attributable to drowsiness or fatigue.
    On June 12, 2003, Public Citizen, Citizens for Reliable and Safe 
Highways (CRASH) and Parents Against Tired Truckers (PATT) filed a 
petition to review the new hours-of-service rule with the United States 
Court of Appeals for the District of Columbia Circuit (D.C. Circuit). 
On July 16, 2004, the D.C. Circuit issued an opinion holding that the 
rule was arbitrary and capricious because the Agency failed to consider 
the impact of the rules on the health of drivers, as required by 49 
U.S.C. 31136(a)(4). Public Citizen et al. v. Federal Motor Carrier 
Safety Administration, 374 F.3d 1209, at 1216. The D.C. Circuit noted, 
however, that neither Public Citizen nor the court was ``suggest[ing] 
that the statute requires the agency to protect driver health to the 
exclusion of those other factors [i.e., the costs and benefits of the 
rule], only that the agency must consider it.'' Id. at 1217 (emphasis 
in original). Although FMCSA argued that the effect of driver health on 
vehicle safety had permeated the entire rulemaking process, the court 
said that driver health and vehicle safety were distinct factors that 
must be considered separately.
    In dicta the court also stated that: (1) FMCSA's justification for 
increasing allowable driving time from 10 to 11 hours might be legally 
inadequate because the Agency failed to show how additional off-duty 
time compensated for more driving time, and especially

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because it failed to discuss the effects of the 34-hour recovery 
provision; (2) splitting off-duty time in a sleeper berth into periods 
of less than 10 hours was probably arbitrary and capricious, because 
FMCSA itself asserted that drivers need 8 hours of uninterrupted sleep; 
(3) failing to collect and analyze data on the costs and benefits of 
requiring electronic on-board recording devices (EOBRs) probably 
violated section 408 of the ICC Termination Act, which requires FMCSA 
to ``deal with'' EOBRs; and (4) the Agency failed to address or justify 
the additional on-duty and driving hours allowed by the 34-hour 
recovery provision.
    On September 1, 2004 (69 FR 53386), FMCSA published an ANPRM 
requesting information about factors the Agency should consider in 
developing performance specifications for EOBRs. As the Agency said in 
the preamble to that document, ``FMCSA is attempting to evaluate the 
suitability of EOBRs to demonstrate compliance with the enforcement of 
the hours-of-service regulations, which in turn will have major 
implications for the welfare of drivers and the safe operation of 
commercial motor vehicles.'' The ANPRM asked for comments and 
information, both on technical questions relating to EOBRs, and on the 
potential costs and benefits of such devices. The EOBR rulemaking has 
been and will remain separate from this hours-of-service rulemaking. 
(For additional discussion of EOBRs, see Section J.13.)
    On September 30, 2004, the President signed the Surface 
Transportation Extension Act of 2004, Part V (Public Law 108-310, 118 
Stat. 1144). Section 7(f) of the Act provides that ``[t]he hours-of-
service regulations applicable to property-carrying commercial drivers 
contained in the Final Rule published on April 28, 2003 (68 FR 22456-
22517), as amended on September 30, 2003 (68 FR 56208-56212), and made 
applicable to motor carriers and drivers on January 4, 2004, shall be 
in effect until the earlier of--(1) the effective date of a new final 
rule addressing the issues raised by the July 16, 2004, decision of the 
United States Court of Appeals for the District of Columbia in Public 
Citizen, et al. v. Federal Motor Carrier Safety Administration (No. 03-
1165); or (2) September 30, 2005.'' (118 Stat. at 1154).

B.2. Notice of Proposed Rulemaking (January 24, 2005)

    FMCSA published an NPRM on January 24, 2005 (70 FR 3339) to 
reconsider the 2003 rule and determine what changes might be necessary 
to correct the deficiencies identified by the court. The Agency used 
the 2003 rule as a proposal for the purpose of soliciting public 
comments, but also announced that ``[t]his rulemaking is necessary to 
develop hours-of-service regulations to replace those vacated by the 
Court'' (70 FR 3342). The NPRM asked a series of questions on driver 
health, sleep loss and deprivation, driving time, sleeper berths, and 
other subjects; the answers are discussed later. While awaiting the 
submission and review of docket comments, the Agency pursued a research 
program to identify relevant studies on the same issues; the results of 
that effort are also described in later sections of the preamble.

C. Executive Summary

    Today's rule requires all drivers of property-carrying commercial 
motor vehicles (CMVs) in interstate commerce to take at least 10 
consecutive hours off duty before driving, limits driving time to 11 
consecutive hours within a 14-hour, non-extendable window after coming 
on duty, and prohibits driving after the driver has been on duty 60 
hours in 7 consecutive days, or 70 hours in 8 consecutive days. Drivers 
may restart the 60- or 70-hour ``clock'' by taking 34 consecutive hours 
off duty.
    These provisions are the same as those of FMCSA's 2003 final rule 
that was vacated by the U.S. Court of Appeals for the D.C. Circuit and 
then reinstated by Congress for the duration of fiscal year 2005. These 
limits, however, are significantly different from the pre-2003 HOS 
regulation, which required only 8 hours off duty before driving, 
allowed 10 hours of driving time, and prohibited driving after having 
been on duty for 15 hours (but allowed any off-duty time taken during 
the work shift to be excluded from the calculation of the 15-hour 
limit). The pre-2003 rule had no counterpart to today's 34-hour 
recovery provision. The recovery role was played by the 60- and 70-hour 
limits, the only element of the pre-2003 rule which has been adopted 
without change for property-carrying vehicles in today's rule.
    The 14-hour driving window and the 10-hour off-duty requirement of 
today's rule combine to move most drivers toward a 24-hour cycle, which 
allows the body to operate in accord with its normal circadian rhythm 
and the driver to sleep on the same schedule each day. A driver may 
remain on duty after the 14-hour window closes or go off duty after the 
11th hour of driving, in each case returning to work after 10 hours off 
duty on something other than a 24-hour cycle. Nonetheless, FMCSA 
believes that most drivers, most of the time, will go off duty at or 
before the end of the 14th hour, since their principal responsibility--
driving--is illegal after that point. The circadian friendliness of 
today's rule is bolstered by the requirement for 10 consecutive hours 
off duty. This is enough time to enable drivers to get the 7-8 hours of 
sleep most people need to maintain alertness and prevent the onset of 
cumulative fatigue.
    The original restart provisions were the 60- and 70-hour limits. 
Drivers could not drive after having been on duty for those periods 
until they had been off duty long enough to reduce their 7- or 8-day 
on-duty totals below the 60- or 70-hour threshold. These limits are 
being adopted in today's rule, but the Agency is also adding a second 
and more flexible recovery provision, as it did in 2003--the 34-hour 
restart. A 34-hour period gives a large majority of drivers the 
opportunity for two night sleep periods, and all drivers the 
opportunity for two consecutive 8-hour sleep periods separated by a 
full 18-hour day. Comments to the docket stated that the 34-hour 
restart provides far more flexibility than the 60- and 70-hour limits 
alone, enabling drivers to tailor their schedules to their business 
requirements while still spending more time at home.
    Today's rule also creates a new regulatory regime for drivers of 
CMVs that do not require a CDL, provided they operate within a 150-mile 
radius of their work-reporting location. These drivers are not required 
to keep logbooks, though their employers must keep accurate time 
records, and the driver may use a 16-hour driving window twice a week. 
Driving time may not exceed the normal 11 hours, but the longer 
operational window twice a week enables short-haul carriers to meet 
unusual scheduling demands. Short-haul drivers rarely drive anything 
close to 11 hours, and available statistics show that they are greatly 
under-represented in fatigue-related accidents. On a per-mile basis, 
long-haul trucks are almost 20 times more likely to be involved in a 
fatigue-related crash. One study suggested that a contributing factor 
to this statistical imbalance is the variety of work short-haul drivers 
typically perform; variety seems to minimize fatigue.
    The rule adopted today balances considerations of driver and public 
safety, driver health, and costs and benefits to the motor carrier 
industry--all factors the Agency is required to take into account. The 
provisions are described separately in the preamble, but they 
constitute an interconnected whole and cannot be adequately understood 
in isolation.

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    The rule addresses driver health issues in detail, and provides a 
lengthy explanation and justification for the requirements adopted 
today. FMCSA has examined a wide range of scientific evidence, 
independently collected, summarized, and reviewed by a health panel 
created at the Agency's request by the Transportation Research Board of 
the National Academies of Science. FMCSA has concluded that the 
operation of CMVs under this rule does not have a deleterious effect on 
the physical condition of drivers. Because relatively little of the 
available evidence was derived from motor carrier operations, the 
Agency had to evaluate and weigh information from different fields and 
adapt it to a trucking environment. We believe our conclusions 
accurately reflect a preponderance of the scientific data. The 
additional off-duty time provided by the rule, along with the 14-hour 
driving window, should have a particularly beneficial effect on 
drivers' sleep opportunities, and indirectly on their health as well. 
In an indication of the fatigue-reducing benefits of the 2003 rule, 
preliminary information on sleep habits under that rule shows drivers 
are getting, on average, at least an additional hour of sleep compared 
to the pre-2003 rule. There is no indication that drivers are averaging 
more hours of work, as opponents of the 2003 rule had feared.
    The Agency has examined all of the data on crash risk. Virtually 
every study has weaknesses or limitations. The largest database on 
fatal truck crashes (Trucks Involved in Fatal Crashes, or TIFA) records 
accidents that occurred entirely under the pre-2003 HOS rule, when off-
duty time could have been as short as 8 hours. Furthermore, while the 
crash risk reflected in TIFA data rises with the number of hours driven 
before the crash, the risk in the 11th hour generally reflects illegal 
driving, since the normal limit at the time was 10 hours. Also, despite 
being the largest database available, the data contain relatively few 
fatigue-related crashes after long hours of driving. All in all, we 
thus must be careful in applying this data to the 2003 rule or today's 
rule, where the minimum off-duty time is 25 percent greater.
    On the other hand, we also examined recent data collected while the 
2003 rule was in effect. Although this data suggests that fatigue-
related crashes have fallen since the 2003 rule became effective, this 
newer data is mostly preliminary, self-reported without statistical 
controls, and also reflects small sample sizes, all of which--once 
again--sometimes leads to inconsistent findings.
    The rule and the Regulatory Impact Analysis discuss the strengths 
and weaknesses of each data source and balance the shortcomings of one 
against the advantages of another. The TIFA data from 1991 to 2002 are 
very comprehensive. In order to ensure that its safety analysis erred 
on the side of caution, the Agency used TIFA data to estimate the risk 
of additional driving hours, knowing that the risk is probably over-
stated given the better opportunities for restorative sleep available 
under the 2003 rule and today's final rule. It is also clear that newer 
CMVs, with their quieter and more comfortable cabs, are less fatiguing 
to drive. That change may also affect the usefulness of the TIFA data, 
though this factor is impossible to quantify.
    Using the most conservative estimates of crash risk for a given 
amount of driving time, FMCSA's analysis shows that the safety 
differential between a 10-hour and an 11-hour driving limit is very 
small while the economic cost differential is very large. The 
operational and scheduling flexibility of an 11-hour limit, even when 
it is not utilized fully, is both economically and socially valuable. 
According to the drivers who commented to the docket, the 11-hour limit 
in the 2003 rule enables them to get home more often, when the 10-hour 
limit would leave them stranded at roadside, out of hours. It also 
allows them to get home without pushing quite as hard as they might be 
tempted to do under a 10-hour limit.
    FMCSA examined a range of options and found that today's rule is 
the only one that is cost-beneficial, with a net annual benefit 
estimated at $270 million. Reducing driving time from 11 to 10 hours, 
while leaving the rest of today's rule intact, would increase net costs 
by $526 million per year. To confirm our findings, we conducted a 
sensitivity analysis of the data and assumptions used. We changed these 
parameters in a way that was unfavorable to today's rule in general and 
to allowing 11 hours of driving in particular. No parameters tested, 
either singly or in combination, produced a basis for either replacing 
the 11-hour driving limit with a 10-hour limit, or suggested that 
another option could be more cost-beneficial.

D. Research Review Process

    In preparing this final rule, FMCSA thoroughly, systematically, and 
extensively researched both U.S. and international health and fatigue 
studies and consulted with Federal safety and health experts. In 
addition, FMCSA asked the Transportation Research Board (TRB) of the 
National Academies to contract with a research team of experts in the 
field of health and fatigue to prepare a summary of relevant literature 
through the TRB Commercial Truck and Bus Safety Synthesis Program. The 
literature review was conducted using two teams of health and 
transportation experts to identify and summarize the available research 
literature relevant to this HOS rulemaking. This review included 
research findings that discussed in a scientific, experimental, 
qualitative, and quantitative way the relationship between the hours a 
commercial motor vehicle driver works, drives, and the structure of the 
work schedule (on-duty/off-duty cycles, time-on-task, especially time 
in continuous driving, sleep time, etc.), and the impact on his/her 
health.
    Dr. Peter Orris, M.D., Professor of Occupational Health at the 
University of Illinois, led a team of six prominent medical doctors, 
epidemiologists, and an ergonomist to identify relevant research on CMV 
driver health. Dr. Alison Smiley, President of Human Factors North 
Inc., Professor in the Department of Mechanical and Industrial 
Engineering, University of Toronto, and the Department of Civil 
Engineering, Ryerson University, led a team of three leading 
transportation and fatigue experts to review relevant fatigue studies. 
Each team conducted two literature reviews, a review of the literature 
at the beginning of the project and a review of the literature that was 
submitted by commenters to the 2005 NPRM. It was through this rigorous 
process that FMCSA ensured that not only the latest research, but the 
best available science was used to support this rulemaking. The final 
reports are located in the docket and are entitled ``Literature Review 
on Health and Fatigue Issues Associated with Commercial Motor Vehicle 
Driver Hours of Work,'' Part I and Part II.
    The driver health team used PubMed Central (PMC), which is the U.S. 
National Institutes of Health (NIH) digital archive of biomedical and 
life sciences journal literature. PMC includes MEDLINE, which is the 
premier bibliographic database covering the fields of medicine, 
nursing, dentistry, veterinary medicine, the health care system, and 
the preclinical sciences. MEDLINE contains over 12 million 
bibliographic citations dating back to the mid-1960s and author 
abstracts from more than 4,800 biomedical journals published in the 
United States and 70 other countries.
    The initial driver health literature search from 1975 to present 
resulted in

[[Page 49982]]

over a thousand research articles. The driver health team screened 
these studies based on relevance to the topics of commercial vehicle 
operator health and the health effects of work hours, shift work, and 
sleep schedules. A total of 55 of the relevant studies were reviewed in 
greater detail. Twenty-five were chosen and summarized by a primary 
reviewer to be included in the Part I final report. The criteria for 
inclusion were the validity of the methodology, the relevance of the 
studied population to truck driving, and the quality of the statistical 
analysis of health outcomes.
    Similarly, the TRB driver fatigue team used the TRANSPORT database, 
a bibliographic database of transportation research and economic 
information produced by the 25-nation Organization for Economic Co-
operation and Development, together with the United States TRB, and the 
31 nations of the European Conference of Ministers of Transport (ECMT). 
TRANSPORT includes the Transportation Research Information Services, 
International Road Research Documentation, and ECMT's TRANSDOC.
    Collectively these sources contain over 530,000 citations from 
publications, most with abstracts, of research information on all 
surface transportation modes, air transport, and highway safety. The 
driver fatigue team searched these studies for relevance concerning 
hours of service, and CMV operator performance and fatigue. Because 
FMCSA had previously docketed summaries of fatigue-related studies used 
in preparing the 2003 rule, the scope of this literature review was 
limited to studies published after 1995. Primary sources were selected 
if they addressed truck driver performance (on road or simulated), and 
included driving performance measures (vehicle control or critical 
incidents). Only studies were selected which involved drivers on 
typical work-rest schedules, involving extended hours of driving, 
driving in a sleep-deprived state, and/or driving at night. After the 
initial set of research reports was screened based on relevance, the 
driver fatigue team reviewed a total of 26 relevant studies, and 13 
were chosen to be summarized for the Part I report.
    As a result of the questions posed in the 2005 NPRM, commenters 
referenced over 200 studies. The driver health and fatigue teams 
reviewed the titles and abstracts of studies referenced by commenters 
using the identical criteria that were used for screening the initial 
research discussed earlier. Articles considered most relevant were 
those involving epidemiological studies, studies of CMV crash risk, or 
field studies of performance of commercial drivers in relation to 
fatigue issues such as daily and weekly hours, time of day, and short 
sleep, or studies of non-CMV drivers showing the effects of sleep loss 
and comparing sleep loss and alcohol impacts. The reasons for not 
reviewing the remaining articles suggested by commenters included the 
following: an article was not published as a report of a recognized 
Agency or in a peer-reviewed journal; an article was very general in 
nature (e.g. a discussion of circadian rhythm); or, an article was not 
sufficiently relevant to the task of CMV driving. The driver health 
team selected 11 of these studies to review and summarize for inclusion 
in the Part II report, while the driver fatigue team selected 21 
studies for the Part II report.
    In addition to reviewing the studies mentioned above, FMCSA 
internally reviewed, summarized, and evaluated research reports that 
were previously cited in the 2003 rule, 2004 litigation, 2005 NPRM, and 
driver fatigue and performance studies that were excluded from the TRB 
literature review (i.e., published before 1996).
    The Agency also assembled an intermodal team of experts on operator 
fatigue and health to help FMCSA further identify and analyze relevant 
research. The Federal agencies represented were the Federal Aviation 
Administration, Federal Railroad Administration, U.S. Coast Guard, and 
the National Institute for Occupational Safety and Health (NIOSH).

E. Driver Health

    The D.C. Circuit held that FMCSA failed to consider the possibly 
deleterious effect of the 2003 hours-of-service rule on the physical 
condition of drivers, as required by 49 U.S.C. 31136(a)(4).
    To assess driver health and better comprehend the impact of the 
findings, one must understand the differences in the types of relevant 
medical research. Epidemiology is the study of diseases in populations 
of humans or animals, specifically how, when, and where they occur. 
Epidemiology attempts to determine what factors are associated with 
diseases (risk factors). Epidemiological studies can never prove 
causation; that is, they cannot prove that a specific risk factor 
actually causes the disease being studied. Epidemiological evidence can 
only show that a risk factor is associated (correlated) with a higher 
incidence of disease in the population exposed to that risk factor. The 
higher the correlation the more certain the association, but it cannot 
prove the causation.
    Another type of study is a dose-response study. A dose-response 
study is based on the principle that there is a relationship between a 
toxic reaction (the response) and the amount of substance received (the 
dose). Knowing the dose-response relationship is a necessary part of 
understanding the cause and effect relationship between chemical 
exposure and illness.
    A third type of study is a case-control study, which investigates 
the prior exposure of individuals with a particular health condition 
and those without it to infer why certain subjects, the ``cases,'' 
become ill and others, the ``controls,'' do not. The main advantage of 
the case-control study is that it enables the study of rare health 
outcomes without having to track thousands of people. One primary 
disadvantage of a case-control study is a greater potential for bias. 
Because the health status is known before the exposure is determined, 
the study does not allow for broader-based health assessment.
    These are important distinctions for the following discussion of 
the research on driver health, specifically regarding exposure to 
environmental stressors such as exhaust, chemicals, noise, and 
vibration. FMCSA has reviewed and evaluated the available and pertinent 
information concerning driver health, with emphasis on chronic 
conditions potentially associated with changes from the pre-2003 and 
2003 rules, to this final rule. The research on CMV driver health falls 
into several broad categories: (1) Sleep loss/restriction, (2) exposure 
to exhaust, (3) exposure to noise, (4) exposure to vibration, (5) 
cardiovascular disease, (6) long work hours, and (7) shift work and 
gastrointestinal disorders.

E.1. Sleep Loss/Restriction

    The lack of adequate sleep has been shown to have detrimental 
impacts on the overall health of humans. Research suggests that sleep 
deprivation adversely affects human metabolism as well as the endocrine 
and immune systems [Spiegel, K., et al. (1999), p. 1438]. Chronic 
partial sleep loss is associated with decreased glucose tolerance, 
decreased leptin levels, increases in evening cortisol levels, and 
adverse cardiovascular effects [Spiegel, K., et al. (2004), p. 5770]. 
Consistent with these studies, epidemiologic research demonstrates that 
short sleep duration is modestly associated with symptomatic diabetes 
[Ayas, N. T. et al. (2003), p. 383], cardiovascular disease, and 
mortality [Alvarez, G.G., & Ayas, N. T. (2004), p. 59]. Other studies 
have shown that short sleepers (less than 6

[[Page 49983]]

hours) have hormone and metabolic changes which result in weight gain 
[Hasler, G., et al. (2004), p. 661; Morikawa, Y., et al. (2003), p. 
136; Taheri, S., et al. (2004), p. 210; Vioque, J., et al. (2000), p. 
1683]. Interleukin 6 (IL-6) is a marker of systemic inflammation that 
may lead to insulin resistance, cardiovascular disease, and 
osteoporosis. Sleep loss of as little as two hours per night increases 
daytime IL-6 and causes drowsiness and fatigue during the next day, 
whereas post-deprivation decreases nighttime IL-6 and is associated 
with deeper sleep [Vgontzas, A. N., et al. (2004), p. 2125].
    As to the amount of sleep necessary, the National Sleep Foundation 
recommends 8 hours per day. This standard comes primarily from studies 
by the National Institutes of Health (NIH), which notes that this was 
the mean time period that healthy young adults gravitated to when 
external influences were removed. Not all sleep researchers agree with 
this conclusion, particularly with regard to individual health and 
well-being. Two large-scale studies have found no relationship between 
longer sleep and better health [Kripke, D. F., et al. (2002), p. 131; 
Patel, S. R., et al. (2004), p. 440]. The epidemiological research on 
sleep duration suggests that mortality may even begin to rise with 
sleep durations greater than 8 hours. Likewise, mortality risk 
increases for short sleep durations less than 6 hours per day [Id.].
    The research identified that prior to the 2003 HOS rule, CMV 
drivers were not getting enough sleep (i.e., 7-8 hours per day) as 
needed to maintain individual health. In four major research studies, 
where sleep was verified using either an actigraph watch (wrist-worn 
monitoring device) or electroencephalogram, CMV drivers averaged from 
3.8 to 5.25 hours of sleep per day [Dinges, D. F., et al. (2005), p. 
38; Balkin, T., et al. (2000), p. 4-48; Mitler, M. M., et al. (1997), 
p. 755; Wylie, C. D., et al. (1996), p. ES-10]. These averages are 
below the 6 to 8 hours of sleep that are associated with lower 
mortality or a healthy lifestyle.
    Preliminary data from the following sources suggest that, on 
average, CMV drivers are obtaining more sleep than before under the 
2003 rule, which requires at least 10 consecutive hours of off-duty 
time. First, an ongoing joint National Highway Traffic Safety 
Administration (NHTSA) and FMCSA study conducted in 2005 found that 
drivers were averaging 6.28 hours of sleep per day, a figure that was 
verified with an actigraph watch [Hanowski, R.J., et al. (2005), p.1]. 
Second, in a survey of its membership, the Owner-Operator Independent 
Drivers Association (OOIDA) found that of the 1,264 drivers responding, 
355 or 30 percent of drivers stated that they were getting more rest as 
a result of the 2003 HOS rule with 10 consecutive hours of off-duty 
time. The other 70 percent of the drivers responded that they were 
getting either the same amount of rest or no additional rest was needed 
as a result of the 2003 rule.
    Comparing study findings before and after the 2003 HOS rule change 
suggests that drivers are getting more than an hour of additional sleep 
per night than they previously were able to obtain. While the Agency 
would like to see drivers obtain a sleep period between 7 to 8 hours 
per day to maximize driver alertness, the finding of 6.28 hours of 
sleep per night is within normal ranges consistent with a healthy 
lifestyle and is a vast improvement over previous sleep findings. Based 
on the research that led to the 2003 final HOS rule, FMCSA knew that 
short sleep (less than 6 hours) among drivers was a concern from both a 
safety and health standpoint. As a result, FMCSA increased off-duty 
time to 10 consecutive hours thereby increasing driver sleep by up to 
an additional two hours per day. This final rule adopts the requirement 
for the 10 consecutive hours of off-duty time.

E.2. Exposure to Diesel Exhaust

    The Environmental Protection Agency's (EPA) Health Assessment 
Document for Diesel Engine Exhaust (2002) concluded that ``long-term 
(i.e., chronic) inhalation exposure is likely to pose a lung cancer 
hazard to humans, as well as damage the lung in other ways depending on 
exposure'' [EPA (2002), p. ii].
    Diesel exhaust (DE) is not a single ``thing'' but a mixture of 
hundreds of gases and particles, which differ with the type of engine 
generating them, operating conditions, and fuel formulations. Some of 
the components of DE are known carcinogens (e.g., benzene) and others 
are mutagenic or toxic. Particulates from diesel engines, which 
constitute about 6 percent of the total ambient particulate matter (PM) 
with an aerodynamic diameter of 2.5 micrometers or less (PM-2.5), are 
highly respirable and able to reach the deep lung. Yet EPA has not 
formally declared DE to be a carcinogen. There are several reasons for 
this ambiguity.
    A dose/response curve is the classic means of measuring the effect 
of exposure. A curve is typically established in a laboratory. Very 
high doses are given over a relatively short period, and the 
physiological response is measured. A dose/response curve is assumed to 
be a straight line, which can be extended downward to the lower 
exposures typical of ambient conditions outside the laboratory. If the 
dose/response curve is not a straight line (because the physiological 
response decreases disproportionately when exposure is reduced), the 
curve will overstate the effect of ambient exposure by some unknown 
amount. In that case, long-term population studies might be an 
alternative, provided long-term exposure can be established.
    Attempts to establish a dose/response curve for DE have not 
produced clear-cut results. In animal studies, rats develop lung tumors 
after lifetime inhalation of DE at exposures vastly higher than any 
ambient condition; but these cancers appear to be at least partially 
the result of particle overload, which prevents lung clearance and 
causes chronic inflammation and subsequent lung disease. Chronic 
inhalation studies in mice show equivocal results, and hamsters do not 
develop cancer [Bunn, W.B., et al. (2002), p. S126; EPA (2002), p. 7-
139]. EPA therefore concluded that ``the rat lung tumor response is not 
considered relevant to an evaluation of the potential for a human 
environmental exposure-related hazard'' [Id.]. EPA further noted that 
``[t]he gaseous phase of DE (filtered exhaust without particulate 
fraction) was found not to be carcinogenic in rats, mice, or hamsters'' 
[Id.].
    Although EPA has declared DE to be a ``probable human carcinogen,'' 
based in part on a review of 22 epidemiologic studies of workers 
exposed to DE in various occupations, it also noted that the

    ``Increased lung cancer relative risks generally range from 1.2 
to 1.5, though a few studies show relative risks as high as 2.6. 
Statistically significant increases in pooled relative risk 
estimates (1.33 to 1.47) from two independent meta-analyses further 
support a positive relationship between DE exposure and lung cancer 
in a variety of DE-exposed occupations. The generally small increase 
in lung cancer relative risk (less than 2) observed in the 
epidemiologic studies and meta-analyses tends to weaken the evidence 
of causality. When a relative risk is less than 2, if confounding 
factors (e.g., smoking, asbestos exposure) are having an effect on 
the observed risk increases, they could be enough to account for the 
increased risk'' [EPA (2002), pp. 7-138 and 7-139].

Overall, the evidence is not sufficient for DE to be considered a 
proven human carcinogen because of exposure uncertainties (lack of 
historical exposure data for workers exposed to DE) and an inability to 
reach a full and direct accounting for all possible confounders [Id.].

[[Page 49984]]

    The actual cancer risk involved in operating a diesel-engine truck 
depends on the degree and duration of exposure to DE, and especially to 
smaller particulate matter (PM-2.5). Information on the real-world DE 
exposure of truck drivers is limited by many uncertainties. Because 
trucks spend a great deal of time in motion, the exposure levels of 
different highway, municipal, and regional environments have to be 
collected and combined. Idling time at terminals, in traffic jams, or 
while using a sleeper berth presumably generates higher exposure than 
does highway driving, but estimating the possible combinations of 
conditions for a large population of drivers is difficult. Furthermore, 
because of the long latency period of most cancers, the extent of the 
risk to truck drivers depends on the length of their exposure. This in 
turn is influenced by the factors that existed several decades ago: 
engine design, formulation of diesel fuel, prevalence of smoking among 
driver populations, total particulate levels from all sources, etc. In 
most cases, this information is less well known than comparable data on 
these factors today. Nor can one project previous (assumed) conditions 
forward or current conditions backward; virtually everything about DE 
has been changing in the last few decades and will continue to change 
as EPA tightens the regulations that govern diesel engine design and 
diesel fuel. Also, given EPA initiatives to reduce truck idling, and 
Federal financing available for idle-reduction programs, FMCSA expects 
additional reductions in exposure of CMV drivers to DE.
    Before discussing the studies reviewed by the driver health team, 
it is useful to analyze a potential exposure effect of a feature of the 
2003 rule, which is adopted in this final rule--the availability of 
additional driving and on-duty hours through the use of the 34-hour 
recovery provision. If utilized to the extreme, this would allow 
another 17 hours of driving time and 24 hours of on-duty time in a 7-
day work week, compared to the limit of 60 hours of driving time 
without the recovery provision. To examine the effect of the 2003 rule 
on driver work hours, FMCSA compared an earlier survey of drivers 
operating under the pre-2003 rule with a recently completed survey. In 
a 7-day work week, the 451 drivers who responded to the earlier survey 
worked, on average (driving and other on-duty time), 64.3 hours per 
week [Campbell, K.L., & Belzer, M.H. (2000), p. 104]. In 2005, FMCSA 
evaluated a sample of driver logs and determined that the 489 drivers 
included, with a total of 5,397 7-day periods, worked an average of 
61.4 hours (driving and other on-duty time) per week [FMCSA Field 
Survey Report (2005), p. 4].
    At the annual meeting of the TRB in Washington, D.C. in January 
2005, Schneider National, a large motor carrier, provided a 
distribution of the weekly (8-day period) on-duty hours for its drivers 
(available in the docket for this rule). The data shows that 
Schneider's employee drivers averaged 62 hours on duty per 8-day period 
and its leased drivers averaged 65 hours on duty per 8-day period. In 
addition, J.B. Hunt, another large motor carrier, in comments to the 
NPRM, reviewed the work records of 80 randomly selected over-the-road 
drivers for a 30-day period. J.B. Hunt found that 74 percent of its 
drivers used the 34-hour restart at least once during the 30-day 
period. On average, J.B. Hunt's drivers accumulated 62.25 hours on duty 
per eight-day period.
    This data provides some indication of the hours worked as a result 
of the 2003 rule. Given the data from surveys and comments regarding 
work hours from motor carriers, it does not appear that CMV drivers are 
working on average significantly more hours as a result of the 2003 
rule as compared to the pre-2003 regulation. Consequently, based on 
review of the data, the average exposure of drivers to DE has remained 
essentially unchanged.
    The driver health team identified and reviewed four studies that 
address the issue of hours of work and duration of DE exposure in 
transportation workers. A large case-control study in Germany found 
significant associations between lung cancer and employment as a 
professional driver. The risk reached statistical significance for 
exposures longer than 30 years [Br[uuml]ske-Hohlfeld, I., et al. 
(1999), p. 405]. An exposure response analysis and risk assessment of 
lung cancer and DE found a 1 to 2 percent lifetime increased risk of 
lung cancer above a background risk of 5 percent among workers in the 
trucking industry, based on historical extrapolation of elemental 
carbon levels [Steenland, K., et al. (1998), p. 220]. A large case-
control study of bus and tramway drivers in Copenhagen found a negative 
association between lung cancer and increased years of employment 
[Soll-Johanning, H., et al. (2003), p. 25]. Finally, a meta-analysis of 
29 studies addressing occupational exposure to DE and lung cancer 
showed that 21 of the 23 studies meeting the inclusion criteria, 
observed relative risk estimates greater than one (probability of a CMV 
driver developing lung cancer divided by the probability of the control 
group developing lung cancer). A positive duration response was noted 
in all studies that quantified exposure [Bhatia, R., et al. (1998), p. 
84].
    Several studies have shown an association between truck driving and 
bladder cancer. The driver health team reviewed three studies that 
addressed the association between duration of exposure to DE and 
bladder cancer. A population-based case-control study in New Hampshire 
found a positive association between bladder cancer and tractor-trailer 
driving, as well as a positive trend with duration of employment [Colt, 
J.S., et al. (2004), p. 759]. A large study in Finland found increased 
standard incidence ratios for six types of cancer in truck drivers. 
Cumulative exposure to DE was negatively associated with all cancers 
except ovarian cancer in women with high cumulative exposure [Guo, J., 
et al. 2004, p. 286]. A meta-analysis of 29 studies on bladder cancer 
and truck driving found an overall significant association between 
``high'' exposure to DE and bladder cancer as well as a dose-response 
trend. The authors concluded that DE exposure may result in bladder 
cancer, but the effects of misclassification, publication bias, and 
confounding variables could not be fully taken into account [Boffetta, 
P., & Silverman, D.T. (2001), p. 125].
    As a result of the number of studies showing an association, DE is 
considered to be a ``probable'' carcinogen by the World Health 
Organization and the U.S. Department of Health and Human Services' 
National Toxicology Program. Because of the complexity of proving a 
definitive link between DE and cancer, no organization, other than the 
California EPA, has classified DE as a known carcinogen [Garshick, E., 
et al. (2003), p. 17]. Studies have a great degree of uncertainty due 
to study design and exposure assumptions, measurement issues, and 
synergistic effects of various pollutants, among other variables. 
[Bailey, C.R., et al. (2003), p. 478]. Excluding rats, animal studies 
are overall negative with regard to lung tumor formation following DE 
exposure. In rats, lung tumors are produced by lifetime inhalation 
exposure to many different particle types. These exposures are 
characterized as ``lung overload;'' however, numerous analyses point to 
a lack of relevance of data from lung-overloaded rats to human risk 
calculations, particularly at environmental or ambient levels [Bunn, 
W.B., et al. (2002), p. S122]. As noted earlier, EPA's risk assessment 
on DE, based on long-term (chronic) exposure,

[[Page 49985]]

concludes that DE is ``likely to be carcinogenic to humans by 
inhalation.'' Studies show a causal relationship between exposure to DE 
and lung cancer, but EPA has not concluded that DE is a human 
carcinogen and cannot develop a quantitative dose-response cancer risk. 
The rat inhalation studies underpinning these findings resulted from 
overloading DE and are unrealistic exposure scenarios for humans [Ris, 
C. (2003), p. 35].
    The acute (short-term) effects of DE, which would allow us to 
determine safe exposure levels, are not currently known [Id.]. Also, 
there are not enough human test data to make a definitive risk 
assessment on the chronic long-term respiratory effects of DE. Tests on 
animals, however, suggest chronic respiratory problems exist [Id.]. 
Cleaner burning diesel fuel standards (2006) combined with cleaner 
diesel engine technologies from more stringent emission standards 
(2007) will generate a net reduction in pollutant emissions, despite 
growth in diesel use [Sawyer, R.F. (2003), p. 39].
    EPA models project on a national basis the amount of emissions or 
pollutants expected annually from all mobile sources. These are based 
on estimates of vehicle miles traveled and new vehicles entering and 
old vehicles leaving the inventory, and they reflect changes in vehicle 
emissions standards. The models project emissions for the following 
pollutants: Carbon Monoxide, Oxides of Nitrogen, Volatile Organic 
Compounds, Particulate Matter (PM-2.5), Particulate Matter (PM-10), and 
Sulfur Dioxide. EPA estimates show that vehicle emissions from all 
mobile sources have declined significantly from 1990 to 2005 (average 
35 percent reduction in emissions) and are projected to decline further 
until 2030 (average 55 percent reduction in emissions). DE from heavy 
vehicles represents about 23 percent of all emissions from mobile 
sources. DE from heavy vehicles has also declined from 1990 to 2005 
(average 55 percent reduction in emissions) and is projected to decline 
further until 2030 (average 88 percent reduction in emissions). The 
following chart shows the projections of heavy vehicle DE from the on-
the-road fleet by type of emission from 1990 to 2030. The chart is 
based on U.S. EPA's ``National Annual Air Emissions Inventory for 
Mobile Sources,'' which was conducted for a variety of pollutants 
emitted by on-road vehicles. [EPA (January 2005)]. Mobile source 
emission inventories were directly modeled for 2001, 2007, 2010, 2015, 
2020, and 2030. Other years were obtained by linear interpolation. 
EPA's Air Inventory was developed using the National Mobile Inventory 
Model [EPA (March 2005)].
[GRAPHIC] [TIFF OMITTED] TR25AU05.000

    If diesel or all engine emissions are in fact carcinogenic (not yet 
proven), then the risk of developing cancer is a function of both the 
amount of DE being inhaled and cumulative exposure (time). Based on EPA 
emission projections of lower emissions from on-the-road heavy 
vehicles, continued reduction in health impacts can be expected over 
time.
    It appears that chronic (long-term) exposure to DE may cause 
cancer. The exposure/dose required, however, is currently unknown due 
to the extreme difficulty in measuring and modeling exposure. EPA has 
noted that there is great

``uncertainty regarding whether the health hazards identified from 
previous studies using emissions from older engines can be applied 
to present-day environmental emissions and related exposures, as 
some physical and chemical characteristics of the emissions from 
certain sources have changed over time. Available data are not 
sufficient to provide definitive answers to this question because 
changes in DE composition over time cannot be confidently 
quantified, and the relationship between the DE components and the 
mode(s) of action for DE toxicity is unclear'' [Ris, C. (2003), p. 
35].

    Some of those flaws might be addressed by Garshick's effort to 
quantify lung cancer risk in the trucking industry through an 
epidemiological study using up to 72,000 subjects [Garshick, E., et al. 
(2002), p. 115]. At this time, however, according to EPA,

[[Page 49986]]

NIOSH, the Centers for Disease Control and Prevention, and NIH, there 
is not enough evidence to declare DE a carcinogen. Nonetheless, EPA's 
finding that DE is a probable carcinogen is a cause for concern. EPA 
has therefore adopted new diesel engine performance requirements and 
will by 2007 require refiners to produce low-sulphur fuel [66 FR 5002]. 
EPA's previous and forthcoming regulatory changes lead to a projection 
of dramatically lower DE through 2030, which will greatly reduce any 
health effects of DE exposure.
    Still, the question remains whether today's rule, regarding 
exposure to DE, ensures that ``the operation of commercial motor 
vehicles does not have a deleterious effect on the physical condition'' 
of CMV drivers [49 U.S.C. 31136(a)(4)]. After reviewing all the studies 
mentioned, there is no evidence that today's rule has a deleterious 
effect. This is not to deny the possibility that DE may have some 
impact on truck drivers. The Agency, however, cannot attempt to address 
a problem without data on its extent and severity. The data on exposure 
to DE is notoriously deficient. As Garshick and his colleagues noted,

    ``The ideal marker of DE exposure would be a single marker that 
would be inexpensive, easy to measure, and clearly linked to the 
source of diesel emissions. However, the reality is that DE is a 
complex mixture, and in many real-life scenarios it may not be the 
only important source of exposure to the individual particles and 
gases that constitute DE. In addition, the mechanism of the health 
effects and specific causal agents are uncertain. The best diesel 
exposure marker is likely to be more complex and involve the 
measurements of molecular organic tracers and elemental carbon. The 
nature of the exposure assessment and marker chosen may also depend 
on mechanism of health effect postulated, and may include 
measurement of exhaust gases (such as ozone and nitrogen oxide) in 
the setting of nonmalignant respiratory diseases. Although current 
literature identifies DE as a health hazard, insight into a dose-
response relationship is limited by factors related to both cohort 
selection and exposure assessment. The development of an exposure 
model in the existing DE epidemiologic literature is hindered by a 
lack of exposure measurements upon which an exposure model can be 
developed, uncertainty regarding the best measurement or marker(s) 
indicative of exposure, and uncertainty regarding historical 
exposures'' [Garschick, E., et al. (2003), p. 21].

    One of the best works to date on DE, lung cancer, and truck driving 
is a series of studies by Steenland and his colleagues published 
between 1990 and 1998. The abstract of the 1998 study concludes that, 
``[r]egardless of assumptions about past exposure, all analyses 
resulted in significant positive trends in lung cancer risk with 
increasing cumulative exposure. A male truck driver exposed to 5 
micrograms/m3 of elemental carbon (a typical exposure in 
1990, approximately five times urban background levels) would have a 
lifetime excess risk of lung cancer of 1-2 percent above a background 
risk of 5 percent.'' The difference between 1 percent and 2 percent is 
obviously quite large, but the absence of a dose/response curve for DE 
and uncertainties in the exposure data make greater precision 
impossible.
    In 1999, however, the Health Effects Institute (HEI), a non-profit 
corporation chartered in 1980 to assess the health effects of 
pollutants generated by motor vehicles and other sources, and supported 
jointly by EPA and industry, found significant flaws even in the 1998 
Steenland study. As summarized by Bunn et al. [Bunn, W.B., et al. 
(2002), p. S127], the HEI found that the Steenland study ``quite likely 
suffers from an inadequate latency period, making it completely 
unsuitable for reaching any qualitative or quantitative conclusions 
about the link between DE exposure and lung cancer.'' Furthermore, the 
workers in the study were exposed to an inseparable mix of gasoline and 
diesel fumes. ``Indeed, during the 1960s (the critical years of the 
Steenland study from a latency perspective), diesel fuel represented 
only 4-7 percent of the total fuel sales (cars and trucks). Moreover, 
in the 1960s, gasoline-fueled vehicles had no after-treatment, so that 
emissions from gasoline-fueled vehicles likely would have been 
comparable to those from diesel vehicles'' [Id.].
    Given the uncertain effects of exposure to DE, FMCSA could not 
include this factor in any cost/benefit analysis for any regulatory 
change it wished to consider. Some changes are beyond FMCSA's 
authority. EPA has exclusive authority to set emission standards for 
new trucks, and NHTSA has comparable jurisdiction over equipment 
standards for new vehicles. FMCSA retains a degree of authority to 
order the retrofitting of safety equipment to vehicles already in 
service [see 49 CFR 1.73(g)], but it is unclear what CMV equipment, if 
any, could be installed on the current fleet to reduce the driver's 
exposure to DE. A driver's ability to open one or both side windows 
could defeat any air-cleaning technology that might be added to the 
tractor, and all drivers spend time outside the vehicle at terminals, 
truck stops, and other locations where exposure to DE is unavoidable.
    Another possible means of reducing drivers' DE exposure would be to 
curtail driving and on-duty time, or even to limit a driver's career to 
a certain number of years, all in the interest of improved health. As 
indicated above, however, there is no dose/response curve for DE and 
the Agency could not be sure that a given reduction in hours or years 
of service would produce a clear benefit. Forced retirement after a 
certain number of years on the job is especially problematical. There 
is nothing in the legislative history of 49 U.S.C. 31136(a)(4) to 
indicate that Congress wanted FMCSA to protect the health of drivers by 
limiting their livelihood. A limit on driving or on-duty hours for the 
specific purpose of reducing DE exposure seems unnecessary, because the 
available evidence shows that drivers have not increased their driving 
or on-duty time in response to the 2003 rule.
    One of the benefits of the 2003 HOS rule has been that it limits 
driver duty periods to 14 consecutive hours per day with no extensions 
for intervening off-duty periods. Under the pre-2003 rule, drivers were 
allowed a 15-cumulative-hour duty period but could extend their maximum 
duty period indefinitely by taking off-duty time during their workday. 
This perpetuated the problem of excessive waiting time for pick up and 
delivery of freight at shippers and receivers, because the drivers were 
expected to place themselves in off-duty status while waiting. A 1999 
study of dry freight truckload carriers by the Truckload Carriers 
Association (TCA) revealed that drivers spent nearly seven hours 
waiting for each freight shipment that they picked up and delivered.
    The non-extendable 14-hour provision of the 2003 rule has given 
motor carriers greater leverage to insist that shippers and receivers 
reduce waiting time. At the 2005 Annual Meeting of the Transportation 
Research Board (TRB) in January 2005, in Washington, DC, several large 
carriers stated that as a result of the 14-hour rule, they are 
increasingly charging detention fees when shippers and receivers cause 
delays. As a result of the 14-hour provision, shippers and receivers 
have had to improve the efficiency and productivity of loading docks. 
Many drivers have commented that waiting time has been significantly 
reduced. Reduced waiting time has a positive impact on drivers. First, 
it reduces the total duty period for the driver, and reduces 
unproductive and often uncompensated time. Second, loading docks were 
cited by Garshick [Garshick, E. et al. (2003), pp. 24-25] as having 
high levels of DE particulate

[[Page 49987]]

matter. Thus, reduced waiting time reduces driver exposure to DE and 
could have beneficial impacts on driver health.
    Diesel emissions have been falling steadily since the early 1990s 
and will continue to decline for many years to come. To whatever 
unknown extent DE may cause lung cancer, EPA's long-range regulatory 
program is expected to reduce that risk. Three recent developments may 
accelerate that downward trend. The first is the cost of diesel fuel, 
which makes idling more expensive. The second is the spread of local 
regulations that limit CMV engine idling time. The third is the 
proliferation of truck-stop services available to drivers that 
eliminate idling by providing hot or cold air for the sleeper berth, 
cable TV, and internet access through an attachment to the side window 
of the tractor. The expected reduction in engine idling in the next few 
years should amplify the health and environmental benefits of EPA's 
regulations. FMCSA has thus concluded that, while DE probably entails 
some risk to drivers, after a thorough review of the data available, it 
is the Agency's best judgment that, compared to the pre-2003 rule, 
today's rule neither causes nor exacerbates that risk.

E.3. Exposure to Noise

    The Occupational Safety and Health Administration (OSHA) noise 
exposure standard for the workplace for unprotected ears is 90 decibels 
adjusted (dBA) limited to 8 hours per day (29 CFR 1910.95). FMCSA also 
has adopted a 90 dBA noise standard (49 CFR 393.94). Twenty-five 
percent of the work force in the United States is regularly exposed to 
potentially damaging noise [Suter, A.H., & von Gierke, H.E. (1987), p. 
188]. In 1995, the FHWA Office of Motor Carriers conducted a study of 
noise in CMVs. The study showed that noise levels in CMV cabs as 
reported over the previous 25 years (1970-1995) had decreased 
[Robinson, G.S., et al. (1997), p. 36]. The following table summarizes 
noise findings from several studies:

                         Figure 2.--CMV Cab Noise Levels Documented From Several Studies
----------------------------------------------------------------------------------------------------------------
                                              Model year  ( of
              Study  (year)                            trucks)                               dBA
----------------------------------------------------------------------------------------------------------------
Enone (1970)............................  1960s era (4)...................  >100 dBA.
Morrison & Clark (1972).................  1960s era (16)..................  85-90 dBA.
Hessel (1982)...........................  1972-1977 (8)...................  74-87 dBA.
Reif & Moore (1983).....................  1968-1978 (58)..................  85-90 dBA.
Morrison (1993).........................  1993 (4)........................  < 80 dBA.
Micheal (1995)..........................  1995 (6)........................  < 80 dBA.
Van den Heever (1996)...................  1995 (16).......................  83 dBA.
Robinson (1997) \1\.....................  1990-95 (9).....................  89 dBA.
Seshagiri (1998) \1\....................  400 measurements................  83+ dBA.
----------------------------------------------------------------------------------------------------------------
Note 1: Study findings added to the table reported by Robinson (1997).

    The truck-cab noise levels for nine trucks Robinson et al. 
evaluated were found to be 89.1 dBA for eight conditions of highway 
driving. This was very close to the FMCSA permissible exposure limit of 
90 dBA. A sound dosimeter \1\ was used to determine the noise doses 
experienced by 10 truck drivers during normal commercial runs of 8 to 
18 hours. The noise doses were measured with rest breaks, meal breaks, 
and refueling breaks included, so they represented realistic 
projections of actual truck trip noise doses experienced by drivers. 
Robinson et al. also conducted pre- and post-workday audiograms for a 
group of 10 drivers. Those results indicated that CMV drivers suffered 
no temporary hearing loss after a normal driving shift.
---------------------------------------------------------------------------

    \1\ A sound dosimeter is an instrument used to measure exposure 
to sound.
---------------------------------------------------------------------------

    In a more recent study of tractors of different models, makes, and 
ages operating on routes that covered different types of Canadian 
terrain, noise exposure was measured (over 400 measurements) under 
several conditions. The noise level recorded ranged from 78 to 89 dBA, 
with a mean of 82.7 dBA. The noise levels increased by 2.8 dBA with the 
radio on, 1.3 dBA with the driver's side window open, 3.9 dBA with both 
the window open and radio on, and 1.6 dBA for operations on four-lane 
highways. Cab-over-engine vehicles appeared to be quieter than 
conventional tractors by about 2.6 dBA. Long-haul (city to city) 
operations on hilly terrain appeared to be quieter than on flat terrain 
by about 2.2 dBA, probably indicating the strong effect of speed (tire, 
wind, and engine noise). These researchers found conditions where CMVs 
exceeded the Canadian noise limit of 85 dBA, mainly when the radio was 
on and the driver's side window open [Seshagiri, B. (1998), p. 205].
    In its comments to the docket, the American Trucking Associations 
(ATA) reported that modern tractors usually have dBA levels ``in the 
low 70's'' and that a ``typical Class 8 sleeper tractor cruising at 60 
mph on level ground pulling a load will have a sound pressure level of 
about 69-73 dBA.''
    The research discussed earlier suggests cab noise levels are well 
within FMCSA's 90-dBA noise standard. The noise levels documented have 
not been shown to exceed OSHA or FMCSA standards. Therefore, the noise 
levels in CMVs should not result in significant hearing loss over a 
lifetime of on-the-job exposure, even if drivers drove the maximum 
hours allowed by this final rule.

E.4. Exposure to Vibration

    Exposure to whole body vibration (WBV) is believed to cause 
fatigue, insomnia, headache, and ``shakiness'' shortly after or during 
exposure. After daily exposure over a number of years, WBV can affect 
the entire body and may result in a number of health disorders. 
Occupational exposure to WBV may contribute to circulatory, bowel, 
respiratory, muscular, and back disorders. The combined effects of body 
posture, postural fatigue, dietary habits, long hours, and loading and 
unloading are the possible other causes for these disorders.
    Vibration in CMVs is a function of the age and maintenance of the 
vehicle, speed, type of roadway, and driving behavior and performance; 
and the most important variable is the condition of the roadway. There 
are no vehicle manufacturing or operational standards for the control 
of WBV, either in this country or abroad. The medical and research 
communities use the 1997 International Standards Organization (ISO) 
2631-1 guidelines for evaluating WBV.

[[Page 49988]]

    Teschke conducted a thorough review of the research on WBV and back 
disorders (including over 99 studies). This research found a number of 
potential risk factors associated with lower back pain (LBP). Besides 
WBV, the study identified a number of other confounding variables that 
are associated with lower back pain. The following risk factors have 
been found identified in the review of research in this area: (1) 
Driver's age, (2) working postures, (3) repeated lifting and heavy 
lifting, (4) smoking, (5) previous back pain, (6) falls or other 
injury-causing events, (7) stress-related factors including job 
satisfaction and control, and (8) body condition and morphology 
including weight, height, physical condition, and body type [Teschke, 
K., et al. (1999), p. 7]. The number of potential risk factors and 
confounding variables makes it difficult to isolate the effects of WBV, 
or even to conclude that WBV is the cause of lower back pain.
    A recent study of volunteer drivers at a large transport company in 
Canada found that operators were not on average at increased risk of 
health effects from daily exposure when compared to the ISO guidelines. 
The study did, however, find several instances where drivers in a 10-
hour shift were exposed to WBV levels established in an earlier ISO 
standard. These instances were highly correlated to road conditions 
[Cann, A.P., et al. (2004), p. 1432]. One of the criticisms of this 
study was that vibration was measured at the floor or base of the 
driver's seat, and measurements did not take into account the 
attenuation of vibration by the driver's seat. Most seats in CMVs today 
are air suspended to better isolate the driver from vibration.
    Much of the WBV research is based on self-reporting through surveys 
and questionnaires to identify factors that are associated with lower 
back pain and back problems. For instance, a questionnaire study of bus 
and truck drivers in Vermont and one in Sweden found a significant 
association between long-term vibration dose and low back pain 
[Magnusson, M.L., et al. (1996), p. 710]. Another questionnaire survey 
in the Netherlands found significant associations between vibration and 
low back pain as well as a significant dose-response [Boshuizen, H.C., 
et al. (1990), p. 109]. A recent review of the health literature on WBV 
and lower back pain (LBP) concluded that, while ``there is probably an 
association between WBV and LBP,'' there was no evidence of dose-
response [Lings, S. & Leboeuf-Yde, C. (2000), p. 290].
    Studies addressing musculoskeletal disorders in truck drivers by 
and large evaluate the effects of WBV. A questionnaire survey of 
Japanese truck drivers found short resting time and irregular duty time 
to be significant risk factors for lower back pain. It also found 
positive but insignificant associations with long driving time per day 
and week, but the hours classified as long were not specified 
[Miyamoto, M., et al. (2000), p. 186]. A study of knee pain in taxi 
drivers found a significantly increased risk of knee pain in workers 
with more than 10 hours of daily driving. A significant dose-response 
trend was also seen [Chen, J.C., et al. (2004), p. 575].
    Our review of the literature on WBV and its potential health 
effects, such as low back syndrome, is inconclusive because the studies 
rely primarily on self-reporting and application of risks derived from 
other environments. The literature related to commercial driving and 
other musculoskeletal disorders suffers from the same limitations. A 
causative relationship can only be viewed as suggestive within this 
context.
    The studies that tested vibration in CMVs found that vibration was 
close to the ISO health risk threshold, but it did not consistently 
exceed the threshold. The introduction of new trucks, which reduce the 
driver's exposure to WBV, would be expected to mitigate any potential 
effects of vibration. ATA submitted comments to the docket that modern 
truck cabs are much quieter, are well ventilated, and have well 
designed, efficient heating and air conditioning units. Physical stress 
on drivers, including road vibration, is reduced by power steering. 
Many trucks are also equipped with automatic transmissions, further 
reducing stress. Improved suspension gives the driver a better ride, 
and provides better handling. ATA maintained that the comfort and 
safety improvements in truck tractors improve the driver's conditions, 
leading to a reduction in stress and fatigue. Two carriers also 
commented that modern trucks have greatly reduced noise and vibration.
    Much of the research on whole body vibration within a CMV and its 
effects on lower back pain or musculoskeletal disorders was based on 
subjective measures and only weak associations have been found. Given 
all the other confounding factors that have been shown to be associated 
with these conditions (age, postures, lifting, smoking, falls, job 
satisfaction, and body condition, including weight) it is highly 
unlikely that vibration is the cause of LBP or musculoskeletal 
disorders. The few studies of more objective measures of vibration have 
not shown vibration to be, on average, above the health risk level 
(with ISO standard).
    When comparing the 2003 HOS rule to today's rule, it is the 
Agency's best judgment that, based on the studies reviewed and comments 
received, WBV does not pose a significant health risk to CMV drivers.

E.5. Cardiovascular Disease

    Cardiovascular disease (CVD), principally heart disease and stroke, 
is the nation's leading killer for both men and women among all racial 
and ethnic groups. Almost one million Americans die of CVD each year-- 
42 percent of all deaths. CVD does not kill just the elderly--it is 
also the leading cause of death for all Americans age 35 and older. 
More than 16 percent of the deaths due to CVD are individuals 35 to 64 
years old. The causes of CVD are complex. The following table 
identifies some of the known risk factors:

                               Figure 3.--Risk Factors for Cardiovascular Disease
----------------------------------------------------------------------------------------------------------------
         Individual factors                   Occupational factors                    Lifestyle factors
----------------------------------------------------------------------------------------------------------------
Genes
Age                                   Sedentary Work                        Smoking
Gender                                Working Long Hours                    Alcohol/Drug Use
High Cholesterol                      Work Stress                           Sedentary Lifestyle
Amino Acid--Homocysteine              Exposure to Physical Stressors and    Lack of Exercise
                                       Injuries
High Blood Pressure                   Shift Work                            Stress
Obesity                               ....................................  Short Sleep
Diabetes
----------------------------------------------------------------------------------------------------------------
Source: American Heart Association.


[[Page 49989]]

    The NIOSH representative to FMCSA's health group reviewed the 
literature regarding CMV driving and the risk of developing CVD. Since 
1992, a number of population research studies from Sweden and Denmark 
have presented data suggesting an association between driving and CVD. 
In contrast to occupational studies undertaken in the United States, 
these research studies did not attempt to quantify ``hours of service 
driving a truck'' or ``occupational chemical and particulate 
exposures.'' Thus, these studies provide no data that could be used to 
correlate individual or group ``exposures'' and CVD outcomes. No 
studies conducted in the United States were found that permitted 
examination of long hours of driving among truck drivers and the 
possible association with CVD.
    Swedish and Danish population studies provide support for the 
hypothesis that driving occupations have elevated risks for 
cardiovascular disease. Among drivers, Swedish population studies 
indicate the greatest risk elevations occur among bus drivers, with 
relative risks ranging from 50 percent to 114 percent in excess of 
comparison populations [Bigert, C., et al. (2003), p. 333]. The 
greatest risk ratio reported for truck drivers (a relative risk of 
1.66), was reduced to 1.10 following statistical adjustment for 
competing health and disease risk factors. A recent study suggests that 
truck drivers experience no more than a 14 percent elevated risk 
[Bigert, C., et al. (2004), p. 987].
    Most epidemiologists take a fairly rigorous view of relative risk 
values. In observational studies, results are not normally accepted as 
significant if a relative risk ratio is less than 3 and is never 
accepted if the relative risk ratio is less than 2 [Brignell, J. 
(2005)]. In epidemiologic research, increases in risk of less than 100 
percent are considered small and are usually difficult to interpret. 
Such increases may be due to chance, statistical bias, or the effects 
of confounding factors that are sometimes not evident.
    A number of Japanese hospital record studies have examined the 
association between long hours of work (not hours of driving) and acute 
myocardial infarction (AMI). The most recent study suggests that weekly 
work time in excess of 60 hours is related to increased risk of AMI 
[Liu, Y., & Tanaka, H. (2002), p. 447]. This research suggests a two-
fold increased risk for overtime work (crude risk of 2.1, reduced to 
1.81 after statistical adjustment for competing health and disease risk 
factors). The authors conclude that overtime work and insufficient 
sleep may be related to the risk of AMI.
    Research is under way at NIOSH to evaluate mortality risk of 
independent truck drivers in the United States. However, this study is 
not designed to collect data on hours of service and other CVD risk 
factors.
    FMCSA's NIOSH representative concluded that current research 
suggests the presence of only a weak association between CVD and truck 
driving. Additionally, CVD is associated with many other occupational 
types. No research studies were found that permitted an examination of 
whether additional hours of driving a CMV impacts driver health as 
measured by increased CVD or AMI. After thoroughly reviewing the 
collective data, in the Agency's best judgment, based on the research 
available, nothing implicates today's HOS rule in a heightened risk of 
CVD or AMI.
    Any increased risk of CVD or AMI may be mitigated by the increased 
off-duty time (10 hours off duty) as well as the increase in 
stabilization from the pre-2003 rule to the 2003 and today's rule of 
the drivers' schedules (circadian rhythm). Changes implemented in truck 
cab design, reducing exposure to exhaust, whole body vibration, and 
noise may also mitigate the risk of CVD and AMI as well.

E.6. Long Work Hours

    The average number of hours worked in the United States annually 
has increased over the past several decades and currently surpasses 
most countries in Western Europe and Japan [Caruso, C.C., et al. 
(2004), p. 1]. Worker health and safety is a growing area of concern, 
and thus more attention is being placed on whether there should be 
limits on hours of work--similar to the hours of service regulations 
for CMV drivers. The primary question being asked is whether there are 
more adverse health consequences as a result of longer hours of work.
    Beyond the previous study mentioned regarding CVD and long hours 
[Liu, Y., & Tanaka, H. (2002), p. 447], the driver health team was able 
to find only one other study that met their selection criteria and was 
directly related to CMV drivers and long work hours [Jansen, N.W.H., et 
al. (2003), p. 664]. This study focused on employees from 45 companies 
in the Netherlands. Self-administered questionnaire data from 12,095 
employees of the Maastricht Cohort Study on Fatigue at Work were used. 
The researchers concluded that employees needed greater recovery 
because their recovery scores (subjective measure of the self-perceived 
need for rest) were significantly elevated in those working 9 to 10 
hours per day, more than 40 hours per week, and frequent overtime 
[Id.].
    The lack of research literature on driver work hours required the 
driver health team to expand its literature review into occupations 
other than transportation workers. Particularly useful was a study 
published by NIOSH in April 2004 entitled ``Overtime and Extended Work 
Shifts: Recent Findings on Illnesses, Injuries, and Health Behaviors'' 
[Caruso, C.C., et al. (2004)]. The NIOSH report documents published 
research on long work hours (greater than 8 hours work per day) and an 
extended work week (greater than 40 hours per week).
    The NIOSH review generally concluded that long work hours appear to 
be associated with poorer health, increased injury rates, more 
illnesses, or increased mortality. NIOSH found that individuals working 
long hours generally have greater risk of unhealthy weight gain, 
increased alcohol use, increased smoking, increased health complaints, 
increased injuries while working, poorer neuropsychological 
performance, reduced vigilance on task measures, reduced cognitive 
function, reduced overall job performance, slower work, and decreased 
alertness and increased fatigue, particularly in the 9th to 12th hours 
of work. The adequacy of these study findings is addressed later in 
this section of the preamble.
    The NIOSH review examined the relationship between hypertension (a 
risk factor for CVD) and long hours. It concluded that the research 
findings regarding hypertension were inconsistent. Park [Park, J., et 
al. (2001), p. 244] found no correlation between the hours worked by 
Korean engineers, whose work hours during the previous month ranged 
from an average of 52 hours to a high of 89 hours per week, and 
increased hypertension. This study is relevant because the work-hour 
limits are reasonably close to the limits a CMV driver could work under 
this final rule.
    CMV drivers, on average, work slightly more than 60 hours per week, 
but FMCSA operational data show they rarely reach the maximum of 84 
work hours per week. This number of work hours is beyond the typical 
number of work hours examined by the research in the NIOSH review. The 
NIOSH review did, however, examine three studies that identified the 
relationship between very long shifts and immune function or 
performance. Nakano [Nakano, Y., et al. (1998), p. 32] reported better 
immune function in taxi drivers who were allowed to work overtime as 
compared with drivers having work-hour

[[Page 49990]]

restrictions. This study examined taxi drivers working 48-hour or 
longer shifts in 1992 and again in 1993. Leonard [Leonard, C., et al. 
(1998), p. 22] reported declines in two tests of alertness and 
concentration in medical residents who had worked 32-hour on-call 
shifts. They reported no significant declines in a test of psychomotor 
performance or a test of memory. A survey of anesthesiologists linked 
long working hours to self-reported clinical errors [Gander, P.H., et 
al. (2000), p. 178].
    Two studies in the NIOSH review identified the relationship between 
long hours and compensation. Siu and Donald [Siu, O.L., & Donald, I. 
(1995), p. 30] and van der Hulst and Geurts [van der Hulst, M., & 
Geurts, S. (2001), p. 227] suggested that compensation may reduce 
adverse effects of long work hours. Siu and Donald [Siu, O.L., & 
Donald, I. (1995), p. 31] reported a relationship between perceived 
health status and overtime pay. Men from Hong Kong who received no 
payment for overtime reported more health complaints when compared with 
men who received payment. In addition, van der Hulst and Geurts 
examined the relationship between reward and long working hours in 
Dutch postal workers. Rewards included salary, job security, and career 
opportunities. They reported that high pressure to work overtime in 
combination with low rewards was associated with a three-fold increase 
in the odds for somatic complaints as compared with a reference 
category of low overtime pressure in combination with high rewards. 
Alternatively, high pressure in combination with high rewards did not 
differ from the reference category. [van der Hulst, M., & Geurts, S. 
(2001), p. 227] This research suggests that if workers are adequately 
compensated for their time, they are less likely to have health 
complaints. This is an important variable that can play a significant 
factor in conducting subjective types of research on the effects of 
long work hours and health. It also raises concerns regarding most 
subjective data regarding the health consequences of long hours that do 
not look at compensation as a factor.
    With regard to the relationship between long work hours and worker 
health, the NIOSH review concluded that ``research questions remain 
about the ways overtime and extended work shifts influence health and 
safety. Few studies have examined how the number of hours worked per 
week, shift work, shift length, the degree of control over one's work 
schedule, compensation for overtime, and other characteristics of work 
schedules interact and relate to health and safety. Few studies have 
examined how long working hours influence health and safety outcomes in 
older workers, women, persons with pre-existing health problems, and 
workers with hazardous occupational exposures.''
    The NIOSH review of the literature on long work hours documents a 
significant lack of data on general health effects. NIOSH reported that 
even when looking at fatigue and accidents, identifying ``differences 
between 8-hour and 12-hour shifts [is] difficult because of the 
inconsistencies in the types of work schedules examined across studies. 
Work schedules differed by the time of day (i.e., day, evening, night), 
fixed versus rotating schedules, speed of rotation, direction of 
rotation, number of hours worked per week, number of consecutive days 
worked, number of rest days, and number of weekends off'' [Caruso, 
C.C., et al. (2004), p. IV].
    Additionally, van der Hulst conducted a review of 27 recent 
empirical studies of long work hours [van der Hulst, M. (2003), p. 
171]. He showed that long work hours are associated with some adverse 
health outcomes as measured by several indicators (CVD, diabetes, 
disability retirement, subjectively reported physical health, 
subjective fatigue). He concluded, however, ``that the evidence 
regarding long work hours and poor health is inconclusive because many 
of the studies reviewed did not control for potential confounders. Due 
to the gaps in the current evidence and the methodological shortcomings 
of the studies in the review, further research is needed.''
    The driver health team found very little research to evaluate 
specifically the association between long work hours and CMV driver 
health. No research studies were found that permitted an examination of 
whether additional hours of driving or non-driving time would impact 
driver health. Research on other occupations is mixed and does not show 
conclusively that long hours alone adversely affect worker health. 
Also, FMCSA's 2005 survey of driver hours indicates that the 2003 rule 
has not increased the overall number of hours a driver actually works 
(see Section I.1). Overall, this rule improves driver health compared 
to the pre-2003 and 2003 rules through a combination of provisions (see 
discussion of Combined Effects, Section J.11). The Agency has adopted 
the non-extendable 14-hour driving window and the 10-hour off-duty 
requirement; these provisions shorten the driving window allowed before 
2003 by one hour (or more, in some cases) and lengthen the off-duty 
period by two hours. In short, based on current knowledge and the 
limited research that is available, in the Agency's best judgment there 
is no evidence that the number of work hours allowed by the HOS 
regulation adopted today will have any negative impact on driver 
health.

E.7. Shift Work and Gastrointestinal Disorders

    The term ``shift work'' covers a wide variety of work schedules and 
implies that shifts rotate or change according to a set schedule. These 
shifts can be either continuous, running 24 hours per day, 7 days per 
week, or semi-continuous, running 2 or 3 shifts per day with or without 
weekends. Workers take turns working on all shifts that are part of a 
particular system. Shift work is a reality for about 25 percent of U.S. 
workers. Similarly, 22 percent of CMV drivers work between the hours of 
12 p.m. and 6 a.m. [Campbell, K.L., & Belzer, M.H. (2000), p. 115].
    This final rule is intended to make work schedules more regular by 
adhering more closely to a 24-hour clock than the pre-2003 rule. It 
increases the number of consecutive off-duty hours to 10 and provides 
for a non-extendable daily driving window of 14 hours. The pre-2003 
rule provided only 8 hours of consecutive off-duty time and prohibited 
driving after a cumulative total of 15 hours on duty per day. Under 
that rule, however, drivers could extend the 15-hour limit by taking 
off-duty time. Today's rule should provide some health benefits to CMV 
drivers, because, as previously shown, drivers are getting more 
consecutive hours of sleep and will generally adhere more closely to a 
24-hour clock (14 hours on-duty and 10 hours off-duty = 24 hours).
    By minimizing on-duty time and maximizing driving time, however, a 
driver could operate on a backward rotating 21-hour schedule (11 hours 
driving and 10 hours off duty = 21 hours). Although drivers might 
conceivably employ that schedule, data suggests drivers do so only 
rarely. Even when it does occur, this schedule is still beneficially 
closer to 24 hours than the pre-2003 rule, which allowed a backward 
rotating 18-hour work day (10 hours driving and 8 hours off duty = 18 
hours).
    The driver health team examined research on the health effects of 
disrupting the circadian rhythm. The circadian rhythm spans about a 
twenty-four-hour day, exemplified by the normal sleep-waking cycle. 
Circadian rhythms in humans originate from a clock circuit in the 
hypothalamus that is set by information from the optic nerve

[[Page 49991]]

about whether it is day or night. One of the earliest studies and most 
definitive works in the area of shift work by Taylor and Pocock showed 
no relationship between shift work and mortality [Taylor, P.J., & 
Pocock, S.J. (1972), p. 201]. Two recent studies used experimental 
conditions to evaluate the impact of an altered circadian rhythm on 
insulin secretion. The first [Morgan, L., et al. (1998), p. 449] found 
a longer sleep-wake cycle, such as might occur in rotating shift work, 
to be associated with increased insulin resistance and glucose 
response. In the second study, 261 shift workers completed a Standard 
Shift Work survey in an investigation of health and well-being [Barton, 
J., & Folkard, S. (1993), p. 59]. Workers using a forward rotating 
schedule were more likely to complain of digestive and cardiovascular 
disorders than those on a backward rotating system. This finding is 
counterintuitive because most fatigue and shift work research suggests 
that a forward rotating schedule is better from a sleep and fatigue 
standpoint. The authors concluded that the combination of direction of 
rotation and length of break when changing from one shift to another 
may be a critical factor in the health and well-being of shift workers 
[Id., p. 63].
    In a thorough review of the literature on shift work and health up 
to 1999, Scott [Scott, A.J. (2000), p. 1057] concluded that 
gastrointestinal, CVD, and reproductive dysfunctions are more common in 
shift workers, and that these effects may be due to rotating or fixed 
shifts, number of nights worked consecutively, predictability of 
schedule, and length of shift and starting time. Exacerbation of 
medical conditions such as diabetes, epilepsy, and psychiatric 
disorders, as well as the diseases noted above, may occur due to sleep 
deprivation and circadian rhythm disruption. It should be noted, 
however, that individuals with these conditions would not generally be 
qualified to drive under FMCSA's medical standards.
    In a more recent study, Ingre and Akerstedt [Ingre, M., & 
Akerstedt, T. (2004), p. 45] investigated the effects of lifetime 
accumulated night work based on monozygotic (from a single egg) twins. 
The authors studied 169 pairs of twins where one of the two twins 
worked night shifts while the other twin worked day shifts. The 
subjects were all over 65 years old and retired. The study found no 
significant difference between education, weight, body mass index 
(BMI), diurnal or circadian rhythm, habitual rise times, habitual bed 
times, and sleep times. The study found that the twin exposed to night 
work was significantly more likely than the twin exposed to day work to 
report lower ratings of subjective health (17.8% versus 10.7% who 
stated that their health was poor). The study did not look at objective 
measures of health. The most significant finding was how similar the 
twins remained and that shift work did not adversely affect important 
health measures (such as BMI, weight, sleep habits).
    The general consensus in the shift work research community 
therefore is that while certain work schedules may result in health 
problems, there are few epidemiological studies of shift workers, and 
more empirical data is needed. Furthermore, no aspect of the 2003 rule 
or this final rule promotes the use of shift work within the 
transportation industry. FMCSA knows that some drivers will drive at 
night because of backward rotations of schedules or as a result of 
their preference to drive at night. The rule is ``shift-neutral'' with 
regard to driving during the daytime or nighttime. Therefore, in the 
Agency's best judgment, this final rule should pose no greater risk to 
driver health than the pre-2003 and 2003 rules with respect to shift 
work. By promoting 24-hour cycles, today's rule should, in point of 
fact, aid driver health in regard to shift work.

E.8. Efforts to Improve CMV Driver Health

    Recognizing the important role that driver health and wellness play 
in driver safety, performance, job satisfaction, and industry 
productivity, FMCSA began a research project in May 1997 to design, 
develop, and evaluate a model truck and bus wellness program. The 
results of the research led to the creation of the ``Gettin'' in Gear'' 
program to create heightened awareness of and interest in driver health 
and wellness. Materials from this program were distributed within the 
truck and bus industry and provided basic health, nutrition, and 
fitness information to CMV drivers. The ``Gettin'' in Gear'' program 
was found to have a positive health impact on drivers who participated 
in the program, both initially and when the Agency followed-up with 
participants [Roberts, S., & York, J. (1999), pp. 15-28]. This was 
shown in both lifestyle habits (e.g., exercising, resting, eating 
balanced meals) and physical data (e.g., body mass index; pulse; 
diastolic blood pressure; aerobic, strength, and fitness levels).
    In addition, FMCSA has assessed the prevalence of sleep apnea among 
CMV drivers and the safety impacts of this condition. FMCSA is 
currently working with the National Sleep Foundation to develop an 
education and outreach program to inform the motor carrier industry of 
the problem of sleep apnea and how it can be effectively addressed.

E.9. Driver Health Summary

    Today's rule provides for 10 hours of consecutive off-duty time, 
giving drivers the opportunity to obtain 7 to 8 hours of restorative 
sleep per day. Research on the implementation of the 2003 rule shows 
that drivers are sleeping 6.28 hours of verified sleep and this is 
within normal ranges consistent with a healthy lifestyle. Actually, the 
data shows that, compared to pre-2003, drivers are on average sleeping 
more than an hour longer per day.
    On the issue of exposure, FMCSA has not found any evidence that 
drivers are working significantly longer hours as a result of 
implementation of the 2003 HOS rule, although it would be permissive. 
While exposure to diesel exhaust may pose a cancer risk, no definitive 
link has been yet established. Without a definitive link it is 
impossible to determine the actual risk or estimate the societal costs 
of DE to CMV drivers' health. However, based on EPA estimates of lower 
emissions (starting in 1990 and continuing until 2030), and the fact 
that drivers do not appear to be working longer hours, the Agency 
believes that any potential health risk to CMV drivers already has been 
reduced and will be reduced more in the coming years.
    The noise levels documented in the research have not been shown to 
exceed OSHA or FMCSA standards. Therefore, the noise levels in CMVs 
should not result in a significant risk of hearing loss. The studies 
that tested vibration in CMVs found that on average vibration was close 
to the ISO health risk threshold, but it did not consistently exceed 
the threshold. Changes in CMV cabs, diesel fuel, and engine designs 
appear to have greatly reduced any potential health risks associated 
with CMV driving. These changes have reduced drivers' exposure to 
diesel exhaust, vibration, and noise. The research has shown that 
exposure to these stressors do not to pose a significant health risk to 
CMV drivers.
    The research suggests the presence of only a weak association 
between CVD and truck driving. No research studies were found that 
permitted an examination of whether additional hours of driving a CMV 
impacts driver health as measured by increased cardiovascular disease 
or myocardial infarction. In the Agency's best judgment, based on the 
research available, nothing implicates today's

[[Page 49992]]

HOS rule in a heightened risk of CVD or AMI.
    The research on long hours and driver health is very limited. 
Research on other occupations is mixed and does not show conclusively 
that long hours alone adversely affect worker health. Also, FMCSA has 
not found any evidence that drivers are working significantly longer 
hours as a result of the 2003 rule. Therefore, the Agency has concluded 
that there is no clear evidence that the number of work hours allowed 
by the HOS regulation will have any impact on driver health.
    While it is generally believed that shift work may result in health 
problems, there are few epidemiological studies conducted on shift 
workers. The most definitive research of shift work and health showed 
no relationship between shift work and worker mortality. A recent study 
of twins suggests that shift work does not alter important health 
measures (such as BMI, weight, and sleep). Regardless, today's rule is 
``shift-neutral'' with regard to driving during the daytime or 
nighttime. Therefore, as previously stated, in the Agency's best 
judgment this final rule should pose no greater risk to driver health 
with respect to shift work.

F. Driver Fatigue

    Over the past decade FMCSA has been conducting research and 
reviewing the literature on driver fatigue in support of its effort to 
revise the Agency's HOS regulations. In preparing this final rule, 
FMCSA internally reviewed and evaluated numerous research reports that 
were published prior to 1995. The TRB driver fatigue team already 
mentioned conducted a literature review to identify studies concerning 
hours of service and CMV driver performance and fatigue published after 
1995. Additionally, the driver fatigue team reviewed additional studies 
that were referenced in the comments to the 2005 NPRM. The pertinent 
information from all these reviews was used in guiding the development 
of this rule and is discussed in context under the relevant provisions 
in Section J of this preamble. This section provides a discussion of 
driver fatigue research relevant to the various provisions finalized in 
today's rule. The following subsections will discuss research on: (1) 
Issues related to driver fatigue (2) Circadian influences (3) Driving, 
duty, and off-duty times, (4) Split-sleep, (5) Recovery, and (6) Short 
haul. In addition, the Agency's current and future fatigue research 
activities are discussed in Section G of this preamble.

F.1. Issues Related To Driver Fatigue

    This regulation addresses the phenomenon of driver fatigue, i.e., 
the partial and at times total loss of alertness resulting from 
insufficient quantity or quality of sleep. Sleep plays a critical role 
in restoring mental and physical function, as well as in maintaining 
general health. For most healthy adults, 7 to 8 hours of sleep per 24 
hour period appears to be sufficient to avoid detrimental effects on 
waking functions. Young adults, for example, report sleeping an average 
of 7.5 hours per night during the week and 8.5 during the weekend 
[Carskadon, M.A., & Dement, W.C. (2005), p. 18]. In a laboratory study 
that compared the performance of two groups of subjects that spent 7 
and 9 hours in bed, respectively, performance improved throughout the 
study. With 7 hours in bed, impaired performance was only found on the 
more sensitive tasks [Balkin, T., et al. (2000), p. ES-8]. Time in bed 
does not necessarily equate to time asleep; and time asleep does not 
always equate to quality sleep. For example, eight hours in bed is not 
likely to yield the same restorative benefit for someone with a sleep 
disorder or someone sleeping in a noisy, hot/cold, or otherwise 
uncomfortable environment, as it does for a ``normal'' sleeper. Studies 
of shiftworkers show that a given number of hours of sleep obtained 
during the late morning (waking hours) does not yield the equivalent 
amount of restorative sleep as the same number of hours obtained during 
the late night/early morning (sleeping) hours [Monk, T. H. (2005), p. 
676].

F.2. Circadian Influences

    Humans ``are biologically wired to be active during the day and 
sleepy at night'' [Monk, T. (2005), p. 674]. We have a homeostatic 
drive to sleep that interacts with the circadian cycle [Van Dongen, 
H.P.A., & Dinges, D.F. (2005), p. 440]. It has been well established 
that mental alertness and physical energy rise and fall at specific 
times during the circadian cycle, reaching lowest levels between 
midnight and 6 a.m., with, for some people, a lesser but still 
pronounced dip in energy and alertness between noon and 6 p.m. [Van 
Dongen, H.P.A., & Dinges, D.F. (2005), p. 439]. To stay alert 
throughout one's waking period, especially during these circadian 
troughs, most adults require 7 to 8 hours of quality sleep per day. 
Sleep obtained during the daylight hours of the circadian cycle is 
generally of poorer quality than sleep obtained during the nighttime/
early morning ``sleeping hours.'' Working/driving during the ``third 
shift'' (midnight to 6 a.m.) has the combined effect of affording 
poorer quality daytime sleep, while requiring the driver to work/drive 
during times when the physiological drive for sleep is strongest. 
Changes of two or more hours in sleep/wake times cause one to become 
out of phase with the circadian cycle. This disrupts the 
synchronization of behavioral and biological processes (e.g., cognitive 
performance, sleep, digestion, and body temperature), often resulting 
in increased fatigue and performance decrements. Circadian de-
synchronization results from irregular or rotating shifts, especially 
those that are not anchored to a 24-hour day (i.e., that start and end 
at different times each day), resulting in poor quality sleep and 
leading to accumulated fatigue. Backward rotating shifts that start an 
hour or more earlier each day also cause one to become out of sync with 
the circadian cycle, restricting sleep and leading to cumulative 
fatigue. ``Forward rotating shifts--starting at a later time each day-- 
are not as good as a non-rotating shift, but are more compatible with 
the properties of the circadian system than are backward-rotating 
shifts.'' [Czeisler, C.A., et al. (1982), p. 462]. The importance of 
maintaining a 24-hour day was highlighted in the 1998 HOS expert panel 
report [Belenky, G., et al. (1998), p. 5].
    The effects of the circadian cycle on driver alertness are 
addressed in this final rule in the 14-hour maximum on-duty and 10-hour 
minimum off-duty provisions (see Sections J.6 and J.7), which move 
drivers closer to a 24-hour day, while allowing some scheduling 
flexibility. This rule is far better than the pre-2003 HOS rule which 
allowed a backward-rotating schedule of 18 hours per day. Being more 
closely aligned to a 24-hour circadian cycle will allow drivers to 
obtain better rest, mitigate driver fatigue, and improve CMV safety.

F.3. Driving, Duty, and Off-Duty Times

    A review of the past and current research provides support for 
adopting a maximum 14-hour driving window, which, when combined with 
the 10 hours off-duty provision, helps maintain a 24-hour clock 
(circadian cycle) and provides enough time for most drivers to obtain 
adequate sleep before returning to work.
    Two studies that assess the length of driving time have been 
conducted since the 2003 rule went into effect.
    One is an analysis of data from an on-road field test of a drowsy 
driver-monitoring device. The study monitored, among other things, 
driver

[[Page 49993]]

sleep quantity and the number of critical incidents (e.g., crashes, 
near-crashes, and evasive actions) in which the driver became involved, 
and assessed driver fatigue and performance during critical incidents. 
Analysis of the study data, which were collected from May 2004 to May 
2005, found that drivers included in the study were sleeping an average 
of 6.28 hours under the 2003 rule, which requires at least 10 hours off 
duty. For drivers who drove in both the 10th and 11th hour, no 
significant difference was found between the 10th and 11th hours of 
driving with respect to either alertness or involvement in critical 
events [Hanowski, R.J., et al. (2005), p. 9]. A similar but pre-2003 
on-road study [Wylie, C.D., et al. (1996), p. ES-9] with 80 long-haul 
drivers who drove either 10 (U.S. rule) or 13 hours (Canadian rule) 
found that drivers were averaging 5.18 hours sleep per night. Both the 
Canadian and U.S. HOS rules that were in effect at the time required a 
minimum 8 hours off duty. Thus, comparing these two studies, drivers 
working under the 10-hour minimum off-duty rule are averaging over 1 
hour more sleep per night. In the Wylie, et al. [Id.] study, there was 
no difference in the amount of drowsiness observed in video records 
(for comparable daytime segments) between the 10-hour and the 13-hour 
driving times. Self-rating of fatigue increased with driving duration 
even though there were no strong performance changes, leading the 
authors to conclude, ``Time on task was not a strong or consistent 
predictor of observed fatigue'' [Wylie, C.D., et al. (1996), page ES-
9].
    Another study under the pre-2003 rule, ``Trucks Involved in Fatal 
Accidents'' (TIFA) [Campbell, K.L. (2005)], found an increase in crash/
fatality risk with increasing driving time. This study included only 
data on crashes that occurred from 1991 to 2002, prior to the 2003 HOS 
rule change. Additionally, among the 50,000 trucks involved in fatal 
crashes that occurred over the 12-year period, only nine crashes 
involving drivers who drove in the 11th hour of driving were fatigue-
related. Note that these drivers were probably driving illegally, since 
the pre-2003 rule had a 10-hour driving limit.
    A recent study [Jovanis, P.P., et al., (2005)] used time-based 
logistic regression models to develop crash risk estimates by hours of 
driving. While all drivers drive during the first hour of the trip, 
relatively few drive through the 11th hour. Therefore, the sample sizes 
in the 11th hour of driving are typically so small that the resulting 
model has a large standard error, particularly at the upper limits of 
the driving time. As a result, the model's 95 percent confidence 
intervals in the crash risk estimates for the 11th hour of driving show 
that the crash risk could be significantly higher than driving in the 
first hour, or it could be just slightly elevated above the first hour 
of driving. The most likely cause for this inconclusive result is small 
sample size.\2\
---------------------------------------------------------------------------

    \2\ Statistical estimates based on small sample sizes tend to 
have large sampling variations, meaning that detecting statistically 
significant differences between two estimates may not be possible.
---------------------------------------------------------------------------

    Sleepiness, performance decrements and crash risk follow the 
circadian cycle, that is, they peak in the late afternoon at one of the 
circadian low points [Wylie, C.D., et al. (1996), pp. 1-3; Akerstedt, 
T. (1997), p. 106]. This fact emphasizes the value of moving toward a 
24-hour work/rest day. The 14-hour maximum driving window, combined 
with the 10-consecutive-hour minimum off-duty time provided in today's 
rule, moves toward stabilizing the 24-hour clock by helping to avoid 
driver shift rotation, and providing enough time to obtain 7-8 hours of 
sleep for most drivers. Rotating shifts that advance or delay the 
starting time for each subsequent shift can cause drivers to become out 
of phase with their circadian rhythm, depending on the extent of the 
change in their starting time. The 14-hour driving window and 10-hour 
off-duty time provisions of this final rule provide an opportunity to 
maintain a 24-hour work/rest day that will allow drivers to maintain 
circadian rhythm. FMCSA analysis indicates that approximately 22 
percent of CMV drivers drive during the early morning hours (midnight 
to 6 a.m.). These drivers will benefit from the 10-hour minimum off-
duty provision in order to maximize their sleep time.
    Longer daytime work hours combined with good quality and quantity 
of sleep (7-8 hours) per day do not appear to pose a safety or health 
problem to CMV drivers. In a driving simulator study, the schedule of 
14 hours on duty/10 hours off duty for a 5-day week did not appear to 
produce significant cumulative fatigue over the three-week study period 
[O'Neill, T.R., et al. (1999), p. 2].
    In Wylie, et al. [Id.] and other studies, the authors point out 
that many of the drivers showed signs of, or reported, fatigue early in 
the workweek after their ``weekend'' off-duty period [Morrow, P.C., & 
Crum, M.R. (2004), p. 14; Hanowski, R.J., et al. (2000), p.17; Wylie, 
C.D., et al. (1996), p. ES-9], implying that sleep habits on non-work 
days are likely a significant contributor to driver fatigue. FMCSA 
regulations can provide an opportunity for sleep, but drivers need to 
maintain responsible sleeping habits.
    Lin and his colleagues formulated an elapsed time-dependent 
logistic regression model to assess the safety of motor carrier 
operations [Lin, T.D., et al. (1993), p. 2]. Using crash data, this 
model provides estimates of the probability of CMVs having a crash. The 
estimates indicate that increased driving time had the strongest direct 
effect on crash risk. All of the data for these estimates were obtained 
from a single-less-than-truckload motor carrier. This study has many of 
the same problems associated with the time-based logistic regression 
models mentioned earlier; i.e., small sample size in the later hours of 
driving. The authors concluded that crash risks ``are particularly 
disturbing at 8th hour of driving. Unfortunately this is when 
mathematical structure of the model becomes less certain * * * it 
weakens our conviction to recommend reducing driver hours regulations'' 
[Lin, T.D., et al. (1993), p. 10]. Understanding the limitations of 
their models, these authors did not recommend reducing driving time. 
They did, however, recommend increasing the minimum off-duty time from 
8 hours to 10 hours.
    The research findings associated with driving time are conflicting. 
The research on the effects of fatigue in operational (on-road) and 
simulated/laboratory settings generally have found no statistically 
significant difference in driver drowsiness or performance between the 
10th and 11th hours of driving. The research analyzing crash data by 
time of day are typically conducted with small sample sizes, 
particularly in the 10th and 11th hours of driving, and the driver 
samples are arguably not representative of the whole industry. These 
studies generally find increasing risk with longer driving hours. On-
road/simulator studies, however, have found no increase in fatigue or 
critical incidents while driving as many as 11 or as many as 13 hours 
per day. The Agency regards the research on driving time as 
inconclusive. FMCSA is adopting an 11-hour driving limit for the 
reasons given in sections H and J.5. The data on off-duty time is less 
problematical. Drivers appear to be obtaining more sleep as a result of 
the 10-consecutive-hour off-duty provision in the 2003 rule. The Agency 
has therefore decided to adopt a 10-hour off-duty requirement for CMV 
drivers, coupled with a 14-hour driving window. This will move CMV 
drivers toward a more-stable 24-hour clock. Because there is a good 
deal of evidence that hours of continuous wakefulness

[[Page 49994]]

are a better predictor of fatigue than driving time, a 14-hour non-
extendable driving window will help to reduce driver fatigue, compared 
to the extendable 15-hour window included in the pre-2003 rule. See 
Sections H.6 and J.5 through J.7 for a more detailed discussion of the 
Agency's findings and decisions regarding driving, duty, and off-duty 
times.

F.4. Split Sleep

    In the 2003 rule, drivers using trucks equipped with sleeper berths 
were allowed to split their 10-hour off-duty/sleep time into two 
periods of varying length as long as the shorter of the two periods was 
a minimum of two hours. This exception to the 10-consecutive-hours off-
duty rule had, in many instances, resulted in drivers splitting their 
sleep into two periods. Drivers could, for example, divide their sleep 
over two 5-hour periods. The National Transportation Safety Board 
(NTSB) has been critical of the split sleep provision in the past, 
noting that, ``* * * sleep accumulated in short time blocks is less 
refreshing than sleep accumulated in one long time period'' [NTSB 
(1996), p. 46)].
    Sleep becomes fragmented when drivers elect to take their sleep in 
two shorter periods, rather than one 7 to 8 hour period. Fragmented 
sleep has less recuperative value and has been shown to be similar to 
partial sleep deprivation in its effects on performance [Belenky, G., 
et al. (1994), p. 129]. Studies of truck crash fatalities indicate that 
split sleep taken by drivers has an adverse effect on CMV safety. In a 
study of heavy truck crashes and accidents, NTSB cited police accident 
reports that show decrements in performance occurring earlier for 
drivers using sleeper berths. NTSB also found that ``drivers using 
sleeper berths had a higher crash risk than drivers obtaining sleep in 
a bed.'' NTSB reported that ``split-shift sleeper berth use increases 
the risk of fatality more than two-fold;'' and ``[s]plit-sleep patterns 
are among the top three predictors of fatigue-related accidents'' [NTSB 
(1996), p. 46]. In summary, NTSB concluded that accumulating 8 hours of 
rest in two sleeper-berth shifts increases the risk of fatality to 
tractor-trailer drivers who are involved in crashes.
    An earlier study by the Insurance Institute for Highway Safety 
(IIHS) examined the association between sleeper berth use in two 
periods and tractor-trailer driver fatalities [Hertz, R.P. (1988)]. The 
findings from this study were similar to those reported by the NTSB. 
The IIHS found that, ``* * * split-shift sleeper berth use (driving 
without an eight-hour consecutive rest period), increased the risk of 
fatality over twofold;'' and that, ``* * * split-shift sleeper berth 
use increased the risk of fatality in all analyses except those limited 
to urban crashes and local pick-up and delivery crashes'' [Id., p. 7]. 
The results of this analysis also found that accumulating 8 hours of 
rest over two sleeper berth periods increases the risk of fatality to 
tractor-trailer drivers who are involved in crashes. IIHS further 
concludes ``[t]he fact that risk remained the same regardless of team 
status suggests that increased risk of fatality is associated with 
nonconsecutive sleep rather than disturbance from the motion of the 
truck while sleeping'' [Id., p. 11].
    Today's rule is based on the research cited and addresses the 
concerns about driver fatigue resulting from sleep fragmentation by 
requiring a consecutive 8-hour sleeper berth period to allow drivers to 
obtain one primary period of sleep and a second 2-hour off-duty or 
sleeper berth period to be used at the driver's discretion for breaks, 
naps, meals, and other personal matters. The new sleeper berth 
provision is fully described in Section J.9 of this preamble.

F.5. Recovery

    Sleep restriction over several days leads to a degradation in 
alertness and driving performance. When sleep is restricted by extended 
duty periods or night work, cumulative fatigue occurs and an extended 
off-duty period is needed to recover. Past studies have indicated that 
a large percentage of drivers (commercial and noncommercial) get less 
than the commonly recommended 7 to 8 hours sleep per day. [Dinges, 
D.F., et al. (2005), p. 38; Balkin, T., et al. (2000), p. 4-48; Mitler, 
M.M., et al. (1997), p. 755; Wylie, C.D., et al. (1996), p. ES-10]. 
Many drivers who obtain less than their daily requirement of sleep over 
time incur a sleep debt; the resulting cumulative fatigue leads to an 
increased crash risk [Hanowski, R.J., et al. (2000), pp. 11-12]. 
Recovery time is required to restore the mind and body to normal 
function and health, as well as to erase the deleterious effects that 
sleep loss has on alertness and performance.
    The TRB fatigue team found five studies that provided information 
regarding the recovery time needed for CMV drivers after working a long 
week. Four of these studies provide support for recovery periods of 34 
hours or less while only one of these studies supports a recovery 
period longer than 34 hours.
    Two studies suggest that a single 24-hour period is sufficient time 
for a driver to recover from any cumulative fatigue. Alluisi's research 
[Alluisi, E.A. (1972), p. 199] involved subjects who worked 8 hours a 
day for 3 days, followed by a 4 hours on/4 hours off schedule (similar 
to driving with a sleeper berth) over a 2-day period. He found that the 
average performance of drivers dropped to 67 percent of baseline toward 
the end of this period. A 24-hour rest period was sufficient to permit 
recovery back to baseline. A simulator study examined daytime driving 
of 14 hours on/10 hours off over a 15-day period [O'Neill, T.R., et al. 
(1999), p. 36]. These authors found that 24 hours was an adequate 
amount of time for recovery. A third study [Feyer, A.M., et al. (1997), 
p. 541] found a dramatic recovery with respect to fatigue in team 
drivers who stopped overnight in the middle of a 4 to 5 day trip. Thus, 
with less than 24 hours off, a single night of sleep was very helpful 
for recovery. A fourth study [Balkin, T., et al. (2000), p. 1-2] found 
that whether or not 24 hours was sufficient depended on the sensitivity 
of the performance measure used to assess recovery. Subjects who 
carried out performance tasks during the day and were restricted to 3, 
5, or 7 hours in bed at night were fully recovered after 1 day of 
recovery sleep of 8 hours in bed, if the performance measure was lane 
tracking or simulator driving crashes. If the measure was performance 
on the psychomotor vigilance test (PVT), a more sensitive test of 
fatigue, then recovery required more than 24 hours. The group who had 9 
hours in bed during the work period, but were then restricted to 8 
hours in bed during the recovery period, did not perform well on lane-
tracking as well as during the work period, clearly illustrating how 
sensitive and essential one's performance is to even one additional 
hour of sleep.
    The TRB driver fatigue team found two recovery studies that were 
conducted with CMV drivers in a field environment. The Wylie [Wylie, 
C.D., et al. (1997)] study was a small demonstration study of a 
methodology that could be used to evaluate drivers' recovery periods. 
Twenty-five drivers were assigned into small groups (four to five 
drivers) and were used to evaluate different recovery (12-, 36-, and 
48-hour) periods and driving time. None of the recovery periods 
examined were found to be of sufficient length for driver recovery. 
However, the study concluded that the small subject sample limited the 
ability to make reliable estimates of observed effects [Wylie, C.D., et 
al. (1997), p. 27].
    The methodology and sample size nullifies Wylie study findings, and 
the

[[Page 49995]]

Agency has not relied on this study in determining the appropriate 
recovery period for CMV drivers. Balkin [Balkin, T., et al. (2000), p. 
5-1] as discussed in the previous section, found that after 7 days of 
daytime work, when sleep had been restricted to 5 or 7 hours in bed, a 
recovery period of more than 24 hours was required to return to 
baseline levels of the most sensitive performance task. For extreme 
sleep restriction of 3 hours in bed, 72 hours recovery was insufficient 
to bring performance of the PVT task back to baseline.
    While the research on driver recovery appears limited to five 
studies that particularly focus on CMV driver recovery, two simulator 
studies suggest that 24 hours is sufficient for recovery after 70 hours 
of daytime driving [O'Neill, T.R., et al. (1999), p. 2; Alluisi, E.A. 
(1972), p. 199]. One on-the-road study found that drivers achieve 
adequate recovery after 24 hours off duty. Another on-road study 
suggests that 36 hours is not quite sufficient with regard to PVT 
measures, but is adequate for driving parameters, including lane-
tracking performance during daytime driving.
    In balance, most of the research with CMV drivers supports the 
assessment that a recovery period of 34 consecutive hours is sufficient 
for recovery from moderate cumulative fatigue. The importance of two 
night (10 p.m.-6 a.m.) recovery periods was highlighted by the 1998 HOS 
expert panel report [Belenky, G., et al. (1998), p. 13]. The majority 
of drivers (approximately 80 percent) are daytime drivers, and would 
likely start their recovery period between 6 p.m. and midnight. All of 
these drivers would have the opportunity for two full nights prior to 
the start of the next work week. For a more detailed discussion 
regarding the recovery period provision of this rule, see Section J.8 
of this preamble.

F.6. Short-Haul

    Motor carrier operations that are conducted solely within a 150 
air-mile radius from their terminals and require drivers to return to 
their work-reporting location every night are generally considered 
short-haul operations. A review of the research literature revealed 
only a few studies on short-haul operations. The first study reviewed 
was the Massie study [Massie, D.L., et al. (1997)] which found that 
short-haul drivers have significantly fewer fatigue related crashes as 
compared to drivers for longer trips (0.4 percent for short-haul trucks 
compared to 3.0 percent for other trucks). Another important finding 
was that ``class 7-8 trucks [26,001 pounds gross vehicle weight rating 
(GVWR) and up] have a fatigue-related fatal involvement rate 8 times 
higher than class 3-6 trucks [10,001-26,000 pounds GVWR]; over-the-road 
trucks have a rate 18 times higher than local service trucks; and the 
rate for tractors exceeds the rate for single-unit straight trucks by a 
factor of 11'' [Massie, D.L., et al. (1997), p. 35].
    A second study evaluated the stress that short-haul drivers face 
daily. Researchers that administered a cross-sectional questionnaire to 
317 CMV drivers found that short-haul drivers have significantly higher 
stress-related symptoms than the general adult population [Orris, P., 
et al. (1997), p. 208]. These drivers perceived their daily events to 
be more stressful than the norm because of heavy workloads and 
inflexible schedules.
    Hanowski, et al. (1998; 2000) conducted two studies on short-haul 
drivers--a focus group and a field study. The first study provided a 
better definition of what constituted a short-haul driver and the 
varied tasks and demands they encounter [Hanowski, R.J., et al. (1998), 
p. 1]. The focus groups concluded that driving was not their primary 
task, accounting for about 40 percent (less than 5 hours) of their work 
time, scattered throughout the day. The two safety problems most often 
mentioned by short-haul drivers were dealing with poor driving by 
operators of cars, pickups, SUVs, etc., and ``stress due to time 
pressure.'' Additionally, Hanowski, et al. [Hanowski, R.J., et al. 
(2000), pp. 1-162] conducted a field study of short-haul drivers with 
instrumented vehicles to gain a better understanding of critical 
incidents that occur within short-haul operations. A critical incident 
was defined as a near crash event, i.e., an event that without evasive 
action by the driver would likely have resulted in a crash. Of the 249 
critical incidents found in the study, 137 were attributed to ``other'' 
(i.e., non-CMV) drivers, 77 to the short-haul drivers, and 35 were 
attributed to incidents outside the control of the driver, such as an 
animal in the road. Fatigue played a role in only 6 percent of those 
incidents, and no fatigue crashes were reported [Id.].
    In determining whether to allow short-haul drivers additional time 
to complete their deliveries, the Agency relied on both laboratory and 
field research studies which confirm the ability of drivers to work a 
16-hour shift without significant degradation of performance. A 
laboratory study of 48 healthy adults found the critical wake period 
beyond which performance began to lapse was statistically estimated to 
be about 16 hours [Van Dongen, H.P.A., et al. (2003), p. 125]. A study 
of New Zealand drivers found that drivers could maintain their 
performance until about the 17th hour of wakefulness; beyond the 17th 
hour, performance capacity was sufficiently impaired to be of concern 
for safety [Williamson, A.M., et al. (2000), p. 3].
    Some short-haul drivers do accrue fatigue, however, and in a field 
study of CMV drivers, it was found that short-haul drivers take short 
naps of 1- to 2-hours duration in order to reduce any fatigue accrued 
during the course of a normal work day. This study showed that these 
drivers take naps within the work shift while they are waiting for 
their vehicle to be loaded or unloaded or during normal breaks for 
meals [Balkin, T., et al. (2000), p. 4-63]. Short-haul drivers are 
unique in that they do not drive for long periods of time. As 
mentioned, Hanowski [Hanowski, R.J., et al. (2000), p. 17] found that 
only 40 percent of their time is actually spent driving, and that time 
was scattered throughout the day. Therefore, traditional performance 
models (time-on-task) do not apply because periods of driving are 
interrupted during their work day. Based on this evidence, FMCSA has 
concluded that because of the uniqueness of short-haul operations, and 
because short-haul drivers are involved in fewer crashes than long-haul 
drivers, they will be able to maintain alertness and vigilance for an 
additional 2 hours for 2 days per week.
    The short-haul provision in this final rule takes into account the 
available research on short-haul drivers and addresses one of the key 
problems confronted by short-haul drivers--the stress of tight 
schedules. To set the context, the research discussed in Section F, 
``Driver Fatigue,'' and elsewhere in this preamble suggests that driver 
fatigue is much less of an issue with short-haul drivers than with 
long-haul truckers, primarily because they return home nightly. Many 
also have fixed work schedules. Short-haul drivers typically operate 
during the daytime hours and are able to sleep at night, which is 
generally preferable to sleeping during the day. Short-haul drivers do 
not drive for long periods each day, either cumulatively or in a single 
session, and driving is usually followed by the physical activity of 
unloading throughout the day, which improves alertness. Short-haul 
drivers are less likely to fall asleep at the wheel due to driving 
monotony. In addition, short-haul driving generally occurs in urban 
settings requiring high levels of alertness, but also providing more 
stimuli to drivers. Short-haul crashes, when they happen, are more 
likely to

[[Page 49996]]

involve property damage than severe injuries or fatalities. Because the 
short-haul regime adopted by this final rule increases the work window 
available to short-haul drivers, it should relieve them, at little risk 
to CMV safety, from the stress and need to hurry caused by inflexible 
schedules and limited work hours. The new regulatory regime for short-
haul drivers is described in more detail in Section J.10.

G. Current and Future FMCSA Research

    In the 2005 NPRM, the Agency requested information on hours-of-
service research issues, including data gaps and processes, and 
methodologies to facilitate data collection and analysis [70 FR 3350]. 
The Agency received no specific responses to this request. However, 
FMCSA continues to proactively research health and safety issues 
relevant to HOS.
    The FMCSA Research and Technology (R&T) 5-Year Strategic Plan 
outlines a vision for delivering an appropriately targeted research and 
technology program that will assist in fulfilling FMCSA's primary 
mission to reduce crashes, injuries and fatalities involving large 
trucks and motorcoaches. One of the challenges identified in the R&T 5-
Year Strategic Plan is to curtail driver fatigue and lack of alertness. 
Fatigue and the lack of alertness are factors in CMV crashes, but more 
research is needed to better understand the causes of fatigue and 
methods of improving alertness. Hours-of-service rules and driver-
oriented programs will need to be continually evaluated and improved. 
R&T will investigate, by means of simulator and field studies, the 
factors affecting fatigue and the recovery times. Other initiatives 
identified in the R&T 5-Year Strategic Plan will also result in the 
research and evaluation of driver health issues. Moreover, in an effort 
to address the complex HOS health issues confronting CMV drivers, FMCSA 
anticipates working with NIOSH on areas of mutual concern and interest.
    FMCSA is identifying, through the use of surveys, the best 
practices employed by experienced CMV drivers to manage their fatigue. 
This study will be published later this year. In addition, FMCSA has 
the following fatigue-related studies that are under way in 2005 and 
will continue for the next several years.
    This research and survey of best practices may contribute to 
educational initiatives, to technological aids, to the rulemaking 
process on EOBRs, and to other aspects of CMV operation and regulation.

G.1. Fatigue Management Program

    The FMCSA Fatigue Management Program (FMP), under development in 
partnership with Transport Canada, provides managers and drivers with a 
framework for managing driver fatigue through, among other items, 
awareness and education on screening for sleep disorders, biocompatible 
scheduling practices, and an understanding of the need and implications 
of good sleep habits. The program has been developed, pilot tested in 
the U.S. and Canada, and is currently in an evaluation phase where its 
cost and safety effectiveness will be assessed in an operational 
environment. Pending a positive result from the evaluation, the FMP 
materials will be revised and finalized, implementation guidelines will 
be developed, and comprehensive program materials and guidelines will 
be made available to motor carriers and individuals who wish to 
implement them.

G.2. Shift Changes and Driver Fatigue Recovery

    The FMCSA Shift Changes and Driver Fatigue Recovery Study currently 
under way has two primary goals:
     Investigate and make recommendations regarding the minimum 
duration of off-duty periods required for CMV drivers to recover from 
the effects of cumulative fatigue resulting from various work shift 
conditions.
     Complete a study and publish a report with conclusions and 
recommendations from the Shift Changes and Driver Fatigue Recovery 
Study.
    Hours-of-service initiatives in both the United States and Canada 
have highlighted scheduling issues closely related to shift changes, in 
particular, the issue of ``weekend'' recovery from cumulative fatigue. 
Although CMV drivers may take their ``weekends'' on any day of the 
week, the issue of concern is the recovery process that occurs during 
these days off. If some degree of sleep deprivation occurs during the 
workweek for drivers (especially when that week has involved night 
driving and/or shift changes), it is critical that drivers have 
sufficient time off during their ``weekend'' to recover full alertness 
and physical vitality. This continuing research is focusing on the 
recovery process in the context of various schedules including day 
driving, night driving, and rotating shifts. After conducting a review 
of the relevant literature (Phase I), a research plan was developed 
that includes recommended hypotheses to be examined and empirical 
research methodologies to be employed (Phase II). In 2005, a contract 
was awarded to conduct the empirical studies (Phase III). A final 
report stating study conclusions and recommendations (Phase IV) will be 
completed by the end of 2007.

G.3. Advanced Driver Fatigue Alerting Technology

    The objective of FMCSA's Advanced Driver Fatigue Alerting 
Technology research initiative is to increase driver alertness through 
a fatigue-alertness monitor. This will be done by establishing a low 
cost, reliable, comfortable, rugged, and user-friendly driver fatigue 
and alertness technology. Driver fatigue-alerting technology is 
intended to monitor driver drowsiness, provide continual alertness 
level feedback to the driver, and provide alerts and warnings when the 
driver's alertness level falls below a specified threshold.
    Currently, FMCSA in partnership with NHTSA is conducting a proof-
of-concept test of a drowsy-driver detection system based on the 
PERCLOS (percent of time the eyelids are closed 80% or more over a 
given time period) concept. PERCLOS has been demonstrated to be the 
most valid measure of driver fatigue. The current infrared-based 
technology to measure PERCLOS appears to work well at night, but has 
the limitation of not working in daylight, limiting the system's 
utility to night driving. FMCSA plans to explore new technologies and 
combinations of technologies or measures, such as steering, lane 
tracking, etc. that may overcome these limitations, and investigate 
development of a more robust system. The objective is to identify and 
develop a relatively low-cost device to be used primarily to reinforce 
driver fatigue training and promote behavioral change to assure drivers 
are well rested.

G.4. Effects of Vehicle Ergonomics on Driver Fatigue

    The FMCSA Effects of Vehicle Ergonomics on Driver Fatigue 
initiative plans to identify design alternatives to assess the effects 
of vehicle ergonomics on driver fatigue. There have been many human 
factor studies designed to determine the effects associated with 
driving a CMV. However, there are no current studies to determine the 
effects of ergonomics on driver fatigue and CMV safety. Therefore, it 
is difficult for FMCSA to provide guidance or support to ergonomic-
related rules that could improve safety. This study will review the 
project objective, conceive design

[[Page 49997]]

alternatives, examine methods, evaluate feasibility, and develop a 
final design incorporating a pilot study capable of demonstrating the 
approach's viability.

H. Crash Data

    FMCSA compiled and reviewed recent large truck crash data 
throughout the industry to assess the impacts of the 2003 rule on crash 
rates, and to determine if there are ways to improve the 2003 rule to 
better address fatigue and fatigue-related crashes. This review 
consisted of examining the following studies and data sources: (1) 
Trucks Involved in Fatal Accidents (TIFA), (2) Virginia Tech 
Transportation Institute (VTTI) (preliminary), (3) Penn State 
University (preliminary), (4) data submitted in comments to the NPRM, 
and (5) Fatality Analysis Reporting System (FARS).

H.1. Trucks Involved in Fatal Accidents (TIFA) Data

    The Trucks Involved in Fatal Accidents (TIFA) file combines data 
from the FARS with additional data on the truck and carrier collected 
by the University of Michigan Transportation Research Institute (UMTRI) 
in a telephone survey with the truck driver, carrier, or investigating 
officer after the fatal crash. TIFA records six variables: fatigue, 
time of day, power unit type, carrier type, intended trip distance, and 
hours driving since the last 8-hour off-duty period.
    The report used by the Agency [Campbell, K.L. (2005)] reviewed TIFA 
data for the years 1991 through 2002 (the most recent year available). 
The sample size of this file represents over 50,000 medium/heavy trucks 
involved in fatal crashes in the U.S., roughly 1,000 of which were 
fatigue related. The objective of this report was to identify the 
operating conditions where the most fatigue-related crashes occur and 
to determine the association of fatigue risk factors with fatal 
crashes.
    Over the period reviewed, the report found a gradual decline in the 
percent of trucks involved in all fatal crashes where truck driver 
fatigue was present at the time of the crash, with fluctuations around 
the downward trend. Campbell also noted that ``[b]oth prevalence and 
risk point to long-haul tractor drivers as the appropriate focus of 
efforts to reduce the incidence of fatigue.''
    When examining the prevalence of fatigue-related fatal crashes by 
the number of hours driven at the time of the crash, the data reveal 
that the majority of such crashes occur in the early hours of the trip. 
This is largely attributable to exposure, since each trip necessarily 
begins with the first hour, which must be the most frequently driven. 
However, when examining the relative risk of a fatigue-related crash by 
hours of driving, or the number of trucks involved in fatigue-related 
fatal crashes in a given driving hour as a percent of all large trucks 
involved in fatal crashes in the same hour, the results trend 
differently. The likelihood a truck driver was fatigued at the time of 
a fatal crash generally increases with the number of hours driven. TIFA 
data show that the relative risk of a large truck being involved in a 
fatigue-related crash in the 11th hour of driving or later is notably 
higher than in the 10th hour of driving.
    Despite its scope and complexity, however, TIFA data must be 
treated with caution. The number of fatigue-related crashes that 
occurred in the 11th hour of driving or later is extremely small. Of 
the roughly 1,000 trucks involved in fatigue-related fatal crashes 
between 1991 and 2002, only nine were operating in the 11th hour of 
driving time.
    The HOS rule in effect when the TIFA data were collected allowed 
only 10 hours of driving, required a minimum off-duty period of only 8 
hours, and allowed driving within a 15-hour window that could be 
extended by the amount of off-duty time taken during that period. The 
2003 rule, which allows up to 11 hours of daily driving but requires 10 
hours off duty, may have reduced the risk of driver fatigue and thus 
the percent of large truck fatal crashes involving fatigue. The 
applicability of TIFA data under the regulatory environment created by 
the 2003 rule is no longer clear.
    FARS, the source of the crash data for the TIFA study, does not 
contain information on driving hours at the time of the crash. TIFA 
researchers therefore contact the driver (or the employing carrier) 
after the fatal crash to collect such information. However, a good deal 
of time can elapse (more than a year in some cases) between the date of 
the crash and the date the TIFA researcher first contacts the driver 
(or the employing carrier). This delay raises the question whether the 
driver can accurately recall his/her driving time so long after the 
incident.

H.2. Virginia Tech Transportation Institute Study

    FMCSA contracted with the Virginia Tech Transportation Institute 
(VTTI) to collect and analyze data on crash risk during the 10th and 
11th hour of driving as part of an on-the-road driving study VTTI was 
conducting under an FMCSA/NHTSA joint initiative. This study offered an 
opportunity to analyze empirical, real-world data obtained under the 
2003 HOS rule. The primary goal was to determine the effect of the 11th 
hour of driving on driver performance and drowsiness.
    Data collection for the study, ``A Field Operational Test of a 
Drowsy Driver Warning System,'' began in May 2004. All data collected 
through May 1, 2005 were used in this analysis. The researchers have 
found no statistically significant difference in the number of 
``critical'' incidents in the 10th and 11th hours of driving [Hanowski, 
R. J., et al. (2005), p. 9]. The study defines critical incidents as 
crashes, near crashes (where a rapid evasive maneuver is needed to 
avoid a crash) and crash-relevant conflicts (which require a crash-
avoidance maneuver less severe than a near-crash, but more severe than 
normal driving). When the occurrence of critical incidents is used as a 
surrogate for driver performance decrements, there is no statistical 
difference between the 10th and 11th hour of driving. The study has 
also determined that drivers are not measurably drowsier in the 11th 
than the 10th hour of driving. These results may be related to another 
finding, that drivers appear to be getting more sleep under the 2003 
rules than they did when the minimum off-duty period was only 8 hours. 
Compared to four sleep studies conducted under the pre-2003 rules (see 
section E.1), the Hanowski study found that drivers operating under the 
2003 rule are obtaining over 1 hour of additional sleep per day [Id., 
p. 8]
    It should be noted, however, that the study is not yet complete. 
The study involves 82 drivers working for three trucking companies who 
had driven a total of 1.69 million miles as of May 1, 2005, under the 
2003 HOS rule. A copy of this VTTI analysis is in the docket.

H.3. Crash Risk and Hours Driving: Interim Report II

    In January 2003, the Pennsylvania Transportation Institute at 
Pennsylvania State University began work for FMCSA to model the effects 
of various commercial driving operational measures (hours driving, 
hours of rest, multi-day driving patterns) on crashes [Jovanis, P.P., 
et al. (2005)]. This study collected records of duty status (RODS) for 
7-day periods prior to crashes, as well as for a non-crash control 
group. The RODS were collected between January 2004 and December 2004. 
Through time-dependent logistic regression modeling, the study found a 
pattern of increased crash risk associated with hours of driving,

[[Page 49998]]

particularly in the 9th, 10th and 11th hours, and multi-day driving. 
The study also suggests a higher crash risk associated with sleeper-
berth operations. For all operations, the study found that the 11th 
hour of driving has a crash risk of more than three times that of the 
first hour.
    Like the VTTI study, this study is incomplete. All RODS were 
collected from 3 for-hire motor carriers. The researchers obtained RODS 
for 231 7-day periods with one or more crashes and 462 7-day control 
periods with no crashes. Driving in the 11th hour occurred only 34 
times.

H.4. Comments on Crash Risk and Data

    Many companies and associations submitted data on crash and injury 
rates. Figure 4 shows changes in DOT recordable accidents, preventable 
accidents, and injuries under the 2003 rule, as reported in several 
comments. In general, the data show that crash and injury rates were 
lower in the year since the 2003 rule went into effect in January 2004.

                                            Figure 4.--Changes in Accident and Injury Rates From 2003 to 2004
                                                                   [Per million miles]
--------------------------------------------------------------------------------------------------------------------------------------------------------
              Commenter                       Fleet size           Crash or injury type         2003            2004               Percent change
--------------------------------------------------------------------------------------------------------------------------------------------------------
Maverick Transportation..............  1100 power units........  DOT recordable accidents            0.63            0.60  -4.8
                                                                 Preventable accidents...            0.32            0.24  -25
                                                                 Crash-related injuries..  ..............  ..............  -30
Roehl Transport......................  1600 power units........  DOT accidents involving          0.08765         0.06554  -25
                                                                  injuries.
ABF Freight System...................  1635 road tractors......  Over-the-road accidents.           *1.49            1.42  -4.6
                                                                 Preventable road                  *0.715           0.586  -15
                                                                  accidents.
                                                                 Injuries for over-the-    ..............  ..............  -41
                                                                  road drivers.
CR England...........................  2550 power units........  Collision-related         ..............  ..............  -1.9
                                                                  injuries.
Overnite Transportation..............  6000 power units........  DOT recordable accidents            0.84            0.80  -4.8
                                                                 DOT preventable                     0.31            0.31  0
                                                                  accidents.
                                                                 Collision-related         ..............  ..............  -8.6
                                                                  injuries.
Werner Enterprises...................  8700 tractors...........  DOT recordable accidents          0.6898          0.7092  +2.8
                                                                 Chargeable accidents....          0.3311          0.3238  -2.2
J.B. Hunt............................  11,000 tractors.........  DOT recordable accidents  ..............  ..............  -10
                                                                 DOT preventable           ..............  ..............  -16
                                                                  accidents.
                                                                 Driver injuries as a      ..............  ..............  -19
                                                                  result of motor vehicle
                                                                  accidents.
Schneider National...................  13,340 tractors.........  Preventable major (over   ..............  ..............  -36
                                                                  $100,000 in cost
                                                                  accidents.
                                                                 Fatigue-related major     ..............  ..............  -50
                                                                  accidents.
                                                                 Worker's compensation     ..............  ..............  -10
                                                                  claims from vehicle
                                                                  accidents.
ATA survey...........................  77,000 to 79,000 trucks.  DOT recordable accidents            0.60            0.57  -5.0
                                                                 DOT preventable                     0.24            0.24  0
                                                                  accidents.
                                                                 Injuries................            0.81            0.75  -7.4
FedEx................................  71,000 motorized          At FedEx Express,         ..............  ..............  -3.8
                                        vehicles.                 fatigue-related
                                                                  accidents.
                                                                 At FedEx Ground, DOT      ..............  ..............  -9
                                                                  recordable accident
                                                                  rate.
                                                                 At FedEx Freight, driver  ..............  ..............  -4
                                                                  injury rate.
National Private Truck Council.......  63 questionnaires.......  DOT recordable accidents          0.4921          0.4248  -13.7
Minnesota Trucking Association survey  85 questionnaires (61%    Preventable/recordable    ..............  ..............  61% of members reported no
                                        long-haul carriers).      crashes.                                                  change. 33% reported a
                                                                                                                            decrease.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Five-year average. Blank cells indicate data not reported.

    In addition to the information provided in Figure 4, eighteen other 
companies and associations reported a decrease in crash rates, but did 
not provide data to support their claims, and 8 others found little 
change in crash rates between 2003 and 2004. The Commercial Vehicle 
Safety Alliance (CVSA) cautioned that additional data over a longer 
period of time are needed to determine to what extent the 2003 rule has 
impacted large truck safety.
    ATA reported data showing that carriers had statistically 
significant lower average crash rates in 2004, causing ATA to believe 
that the 2003 rule is superior to the pre-2003 rule from the 
perspective of overall safety. Two State government agencies, however, 
pointed out that the FMCSA Motor Carrier Management Information System 
(MCMIS) data show an increase in CMV crashes. FMCSA considered the use 
of MCMIS data to examine changes in truck-related crashes between 2003 
and 2004. However, the Agency decided to utilize FARS data for this 
analysis (see below), in lieu of available MCMIS data, for two reasons. 
First, the MCMIS crash data do not provide researchers the ability to 
isolate fatigue-related crashes, which are critical for this 
rulemaking. FARS data do provide this ability. Second, FMCSA crash data 
experts believe that, for a variety of reasons, MCMIS currently fails 
to capture roughly 20 percent of the fatal crashes that are reported in 
FARS. Because of these MCMIS limitations, FMCSA chose to use FARS data 
for its analysis.
    The information provided by commenters is not available from any 
other source, but there is undoubtedly some variability in the methods 
and accuracy with which the data were collected. Equally important, the 
crash and injury reductions reported by

[[Page 49999]]

commenters cannot be definitively attributed to the effects of the 2003 
rule, though some commenters noted that the rule is the only major 
variable that changed from 2003 to 2004.

H.5. Fatality Analysis Reporting System (FARS)

    FARS is a national census of fatal crashes involving motor 
vehicles, including large trucks. FARS data are reported annually by 
the States, maintained by NHTSA, and are generally recognized as the 
most reliable national motor vehicle crash data available.
    FMCSA began by analyzing the 2003 FARS Annual Report File. Because 
the 2004 Annual Report File had not yet been released at the time the 
analysis for this rulemaking was conducted, FMCSA examined its 
predecessor, the ``Early Assessment File,'' which typically contains 
most of the fatal crashes that eventually appear in both the Annual 
Report and Final FARS data sets. For example, a NHTSA comparison of 
calendar years 2002 and 2003 indicates that the Early Assessment File 
captured at least 75 percent of the total crashes and fatalities later 
included in the Annual Report Files for those years. Since the earlier 
months of the calendar year are reported more completely in the Early 
Assessment File, FMCSA restricted its analysis to the first 9 months of 
2003 and 2004.
    FMCSA examined all fatal crashes involving large trucks from 
January through September of 2003 and 2004, as well as those where the 
truck driver was coded as fatigued at the time of the crash. Results 
from this year-to-year comparison are presented in Figure 5.

                                 Figure 5.--Fatal Crashes Involving Large Trucks
                          [Calendar years 2003 and 2004 (first 9 months of each year)]
----------------------------------------------------------------------------------------------------------------
                                                                                                     Fatigue-
                                                                                                  related (truck
                                                                                                      driver)
                          Calendar year                            Total crashes      Number          crashes
                                                                                                 ---------------
                                                                                                      Percent
----------------------------------------------------------------------------------------------------------------
2003............................................................           3,120              54             1.7
2004............................................................           2,954              43             1.5
Year-to-Year Difference (Number)................................            -166             -11            -0.2
Year to-Year % Difference.......................................            -5.3           -20.4          -11.8
----------------------------------------------------------------------------------------------------------------
Source(s): 2003 Fatality Analysis Reporting System (FARS) Annual File; 2004 FARS Early Assessment File, National
  Highway Traffic Safety Administration.

    Figure 5 shows that the total number of fatal crashes involving 
large trucks decreased by 166, from 3,120 in 2003 to 2,954 in 2004. 
This represents a 5.3 percent reduction. The number of large truck 
crashes where the driver was coded as fatigued dropped by 11 crashes, 
or 20.4 percent. More importantly, however, fatigue-related fatal 
crashes are down from 1.7 percent of all crashes in 2003 to 1.5 percent 
in 2004, an 11.8 percent reduction.
    These reductions in fatigue-related fatal crashes are very small, 
and are not enough to allow final conclusions about the long-term 
impact of the 2003 rule on highway safety. However, the available 
information may suggest that fatigue-related crashes overall are 
trending in the right direction.

H.6. Conclusion

    Available information on the effect of allowing 11 hours of driving 
time is inconclusive. TIFA is a large data set based on crashes that 
occurred across the nation over a relatively extended period. While the 
statistical risk increases rather sharply in the 11th hour of driving, 
in all the years from 1991 to 2002 TIFA classified only 9 fatal crashes 
that occurred in the 11th hour of driving as fatigue-related. 
Furthermore, TIFA data were collected at a time when Federal HOS 
regulations required only 8 hours off duty, and allowed driving within 
an extendable 15-hour window, both of which may have ensured that 
drivers operating in the 11th hour were more fatigued than would be the 
case under the 2003 rule. Finally, the pre-2003 rule allowed only 10 
hours of driving, which means that drivers operating in the 11th hour 
were out of compliance with the rules at the time, and therefore may 
not be representative of drivers legally operating in the 11th hour 
after adoption of the 2003 rule.
    The on-going studies by the Virginia Tech Transportation Institute 
and the Pennsylvania Transportation Institute are being conducted under 
the 2003 HOS rule and therefore avoid one of the problems associated 
with TIFA data. One finds that the 11th hour of driving poses an 
increased crash risk while the other finds no statistical difference 
between the 10th and 11th hours of driving. Because of the relatively 
short time since the 2003 rule was adopted, both studies acknowledge a 
considerable amount of uncertainty which may be resolved once the 
datasets increase.
    Nearly all of the motor carriers and trucking organizations that 
submitted comments to the docket reported lower crash and injury rates 
in 2004, when the 2003 HOS rule was first enforced, than in 2003. This 
downward trend reveals nothing specific to the 11th hour of driving 
time, nor can it be attributed directly to the 2003 rule, but it does 
suggest that the net effect of the various provisions of the 2003 rule 
has not been harmful. However, the data summarized in Figure 4 were 
undoubtedly collected and reported with differing degrees of 
statistical sophistication. Still, the number of drivers employed by 
the carriers that provided information is very large and the downward 
trend in accidents and injuries is unmistakable.
    Preliminary FARS data show that there were fewer fatigue-related 
fatal CMV crashes in the first nine months of 2004, when drivers and 
carriers were subject to the 2003 rule, than in the same months of 
2003, when they were subject to the previous rule. Fatigue-related 
fatal crashes as a percentage of all CMV fatal crashes were also down 
in 2004. This result is similar to the information provided in motor 
carrier comments to the NPRM. The downward trend is clear, but the data 
do not allow a calculation of crash risk for each additional hour of 
driving.
    In short, the available crash data do not clearly indicate whether 
the 11th hour of driving, combined with the other provisions of the 
2003 rule, poses a significant risk. Because the data are not clear, 
for the purposes of this rulemaking's RIA, FMCSA conservatively assumed 
that the increased fatigue crash risk of driving in the 11th hour could 
be explained by the TIFA data as summarized in Campbell 2005, and FMCSA 
tests the robustness of the conclusions of this analysis

[[Page 50000]]

through a sensitivity analysis that assumes an even higher relative 
fatigue crash risk of driving in the 11th hour.
    FMCSA carried out a cost/benefit analysis of a 10- and 11-hour 
driving limit and other aspects of this final rule. The results are 
described fully in section K.1 and in the Regulatory Impact Analysis 
(RIA) filed separately in the docket. Motor carrier operations were 
modeled very elaborately. As discussed above, the Agency used a time-
on-task multiplier based on the TIFA data. The model assumed that the 
risk of the 11th versus the 10th hour of driving increased, as based on 
the TIFA data. FMCSA estimated that a 10-hour driving limit would save 
no more than 9.3 lives per year compared to an 11-hour limit, but at an 
annualized net cost of $526 million ($586 million in gross costs minus 
$60 million in safety benefits), relative to an 11-hour limit. In other 
words, a 10-hour driving limit would cost more than $63 million per 
life saved.
    FMCSA conducted a number of sensitivity analyses regarding the 
relationship between fatigue-related crash risk and driving in the 11th 
hour to test the sensitivity of the RIA results to the assumptions 
built into the model. The sensitivity analyses are contained in Chapter 
6, Section 8, of the RIA.
    While the Agency did not explicitly estimate the marginal costs and 
benefits of limiting daily driving to 8 or 9 hours, FMCSA believes that 
such a change would not be any more cost beneficial than a 10-hour 
limit. This is due to the fact that, while the increase in the relative 
risk of a fatigue-related crash generally rises after the 8th hour of 
driving (according to the TIFA data), the increase is more notable in 
the 10th hour and later. Therefore, since the Agency's economic 
evaluation shows that a 10-hour driving limit results in considerably 
higher costs than benefits, compared to an 11-hour limit (holding all 
other HOS regulations constant), it logically follows that limiting 
driving time to 8 or 9 hours would yield the same result. Additionally, 
limiting daily driving to 8 hours, for instance, could increase the 
impact of a backward rotating schedule for some drivers (8 hours of 
driving + 10 hours off duty = 18 hours) relative to the 2003 rule (11 
hours of driving + 10 hours off duty = 21 hours). Such a change has the 
potential to increase fatigue-related crash risks due to the disruption 
of driver circadian rhythms.
    Although FMCSA's mission is improved CMV and highway safety, the 
Agency is required by statute to consider the costs and benefits of 
requirements it may impose [49 U.S.C. 31136(c)(2)(A) and 31502(d)]. 
Such consideration is clearly expected to influence the Agency's 
rulemaking decisions. The Department of Transportation currently uses 
$3 million as the ``value of a statistical life'' (VSL) for rulemaking 
purposes. A 10-hour driving limit would essentially have a VSL more 
than 21 times the current DOT standard. This cost per life saved is 
substantially higher than the maximum $10 million per statistical life 
cited by the Office of Management and Budget (OMB) in its guidance to 
Federal agencies on conducting regulatory impact analyses [OMB Circular 
A-4, p. 30]. Setting the maximum driving time at 10 hours would impose 
upon the motor carrier industry, an important sector of the American 
economy, regulatory costs entirely disproportionate to regulatory 
benefits. Most of the studies and analyses that report an increased 
crash risk in the 11th hour of driving are based on data collected 
while the driving limit was 10 hours and the minimum off-duty period 8 
hours. The agency expected the new 10-hour off-duty period required by 
the 2003 rule to reduce driver fatigue and improve safety, despite 
allowing 11 hours of driving time instead of 10 hours. Comprehensive 
data to test that assumption are not yet available, but many motor 
carriers have reported lower crash and injury rates under the 2003 
rule, and preliminary FARS data indicates that fatigue-related fatal 
truck crashes have declined, both in number and as a percentage of all 
fatal CMV crashes. This suggests that the pre-2003 studies and data 
connecting the 11th hour of driving with a higher crash risk may no 
longer be relevant because the 2003 rule has created better 
opportunities for restorative sleep, opportunities which drivers have 
used to good effect. In short, it is FMCSA's best judgment that the 
$526 million net cost of a 10-hour driving limit is too high to justify 
the modest benefits it would generate. This factor, coupled with the 
inconclusive nature of available crash data, has led the Agency to set 
the maximum allowable driving time at 11 hours after 10 consecutive 
hours off duty.

I. Operational Data

    To better understand how the motor carrier industry has implemented 
the 2003 HOS rule and to help assess the safety and cost impacts, FMCSA 
compiled and reviewed several data sets on industry's current use of 
the 34-hour recovery provision, the 11th hour of driving, the 14-hour 
tour of duty, and split sleeper berth. Additionally, the Agency 
examined average weekly hours worked after implementation of the 2003 
rule, as well as average nightly sleep. Data compiled or reviewed to 
answer these questions included that obtained from the 2005 FMCSA Field 
Survey, the 2004 Owner-Operator Independent Drivers Association (OOIDA) 
survey, the 2004 Stephen Burks Private Carrier Survey, Schneider 
National, Inc. (a large, for-hire truckload carrier), and the Virginia 
Tech Transportation Institute study.

I.1. 2005 FMCSA Field Survey

    In January 2005, FMCSA initiated a survey by its field staff to 
assess the motor carrier industry's implementation and use of the 2003 
rule. The data collected were based upon the driver records of duty 
status, or time records, as applicable, and included the months of July 
2004 through January 2005. The survey results are based upon the 
collection of data from a cross-section of industry in 44 States, and 
represent a sizeable population of commercial drivers and on-duty 
periods in calendar years 2004 and 2005.
    The project was conducted in conjunction with normal motor carrier 
review activities during the period of January 24, 2005 to February 4, 
2005. While the survey was conducted, all compliance and enforcement 
decisions and actions followed established Agency procedures. To 
enhance the quality of the data collected, the Agency excluded drivers 
that were found to have falsified their records.
    Overall, 269 motor carriers were surveyed, with 542 driver records 
examined. The majority of the survey (81 percent) was completed in 
conjunction with a compliance review; with the remaining (19 percent) 
in conjunction with a safety audit. A compliance review is an in-depth 
review of a motor carrier's compliance with the Federal Motor Carrier 
Safety Regulations (49 CFR parts 382 to 399) and Hazardous Materials 
Regulations (49 CFR parts 100 to 180), as applicable. Motor carriers 
are selected for review based upon safety performance or receipt of a 
non-frivolous complaint, or in follow-up to previous compliance/
enforcement actions. A safety audit, on the other hand, is a review of 
the carrier's safety-management practices and controls, and is 
conducted within the first 18 months of the motor carrier beginning 
interstate operations. The safety audit is used to both educate the 
carrier and gather data to evaluate and determine whether the carrier 
has in place basic safety management controls to ensure safe operation 
of CMVs.
    Of the carriers surveyed, 85 percent were classified as for-hire 
motor

[[Page 50001]]

carriers. Of the drivers surveyed, 80 percent were classified as over-
the-road (OTR) drivers. For the purpose of this survey, OTR was defined 
as a driver who did not return to the terminal (work-reporting 
location) or home nightly.
    The survey found the following:
34-Hour Recovery
    Of the 542 drivers included in the survey, 393 (or 72.5 percent) 
used the 34 or more hours recovery provision at least once. For these 
393 drivers, a total of 1,411 recovery periods were recorded. Looking 
at the length of all the recovery periods recorded in the survey 
(1,411), 67 percent exceeded 44 hours, 10.8 percent were 36 or fewer 
hours, and 4.68 percent were the minimum 34 hours. Slightly less than 
27 percent of the drivers had one recovery period of 36 or fewer hours, 
while 11.4 percent had one recovery period of the minimum 34 hours.
11th Hour Driving
    Of the 6,850 driving periods reviewed, 20.7 percent exceeded 10 
hours of driving. This includes 4 percent that reflected driving beyond 
the 11th hour. In those cases where daily driving exceeded 11 hours, 
either the driver was in violation or not subject to the rule at that 
time. Looking just at the driving periods of OTR drivers, FMCSA found 
that 22.9 percent of these driving periods exceeded 10 hours of 
driving.
14 Hour Tour of Duty
    Of the 7,262 tour-of-duty periods reviewed, 15.3 percent exceeded 
12 hours, and 4.3 percent exceeded 14 hours. Looking just at OTR driver 
tours of duty, FMCSA found that 16.4 percent exceeded 12 hours and 4.6 
percent exceeded 14 hours.
Sleeper Berth
    Of the 2,928 sleeper-berth periods recorded, 68 percent exceeded 6 
hours, and 52.6 percent exceeded 8 hours. A comparison of split-
sleeper-berth periods found that the first period typically had longer 
hours (on average 1.5 more hours) recorded than the second split.
Midnight to 6 a.m. (Circadian Trough)
    Of the 9,798 records evaluated, a total of 2,776 (28.3 percent) was 
found to have recorded duty/driving time between midnight and 6 a.m. In 
1,149 of the records (or 11.7 percent) drivers exceeded 3 hours duty/
driving during the midnight to 6 a.m. time period. It should be noted 
that 80 percent of drivers included in this survey were classified as 
over-the-road drivers (or those that did not return to their work-
reporting location nightly), and as such, night driving may be over-
represented in this sample.
Total Work Hours
    On average, drivers recorded 8.78 hours of work per day (driving 
and on-duty not-driving), with a standard deviation in average hours 
worked per day of 2.9 hours. The daily hours worked produce a 7-day 
average of 61.4 hours.
    While the drivers included in this survey are not representative of 
the entire interstate commercial driver population, this survey does 
provide a valuable snapshot of current operations (those under the 2003 
rule), as well as the ``real world'' HOS habits of drivers.

I.2. OOIDA Survey

    The Owner-Operator Independent Drivers Association (OOIDA) 
conducted a web-based survey of its members in 2004 to assess their 
experience with the 2003 rule. The survey comprised 17 questions and 
addressed such issues as the use of daily driving, the recovery period, 
and sleeper-berth provisions, as well as the rule's effect on income, 
wait times, time at home, naps, breaks, hours worked, fatigue, and 
other factors.
    The OOIDA survey asked respondents to provide information on their 
type of operation by identifying themselves as either short-haul, 
regional, or long-haul drivers. However OOIDA provided no definitions 
(i.e., ranges of daily miles driven) for the terms regional, short-, 
and long-haul driver. Of the 1,223 OOIDA members who provided such 
information in their survey responses, 153 (or 12 percent of 
respondents) identified themselves as short-haul drivers with total 
weekly miles averaging 2,041 and average runs (or lengths of haul) of 
387 miles. According to the definition of short-haul operations used in 
the 2003 regulatory impact analysis (RIA), and the definition used in 
the RIA for this final rule, short-haul drivers are those with average 
lengths of haul of 150 miles or less. As such, the self-identified 
``short-haul'' driver respondents to this survey represent what FMCSA 
considers to be regional or long-haul drivers, or those with average 
lengths of haul greater than 150 miles.
    There were 377 respondents to this survey (or 31 percent) who 
identified themselves as regional drivers, for whom total weekly miles 
averaged 2,369 and average runs equaled 629 miles. Lastly, there were 
693 self-identified long-haul drivers (57 percent) in this survey, for 
whom total weekly miles averaged 2,709 and average runs equaled 1,196 
miles. Additionally, 666 (or almost 55 percent) of the 1,223 survey 
respondents indicated that they were leased to a motor carrier, 284 (or 
23 percent) operated under their own authority, and the remaining 273 
(or 22 percent) identified themselves as company drivers.
    Regarding implementation of the 2003 rule, the survey inquired 
about OOIDA member use of the 11th hour of daily driving, 34-hour 
recovery, and split sleeper berth. Results indicate that during the 
month of June 2004 (the period for which information was requested), 
all survey respondents as a single group used the 11th hour of driving 
an average of 8.4 times, the 34-hour recovery period an average of 3.1 
times, and the split-sleeper-berth exception an average of 4.0 times. 
To examine these survey results as a percentage of total work periods 
available to the driver, we divided survey results by 7- and 30-day 
periods, where applicable. For instance, we see that the 11th hour of 
driving was used during 28 percent of the 30 days in June (or 8.4 
divided by 30). Additionally, the split-sleeper-berth-provision was 
used during 13 percent of the total days available (or 4.0 divided by 
30). Lastly, the 34-hour recovery was used in 80 percent of the 3.9 
available work weeks in June 2004 (or 3.1 divided by 3.9). OOIDA 
members who identified themselves as short-haul drivers tended to use 
each of these provisions the least. Regional drivers used the 11th hour 
of driving and the 34-hour recovery the most on average, and long-haul 
drivers used the split sleeper berth the most on average.
    With regard to the rule's potential impact on drivers, one survey 
question asked, ``Have the new HOS regs helped you to establish and 
maintain a 24-hour work/rest cycle?'' 34 percent of driver respondents 
felt that the 2003 rule had in fact helped them to establish and 
maintain a 24-hour cycle, while 64 percent indicated they experienced 
no improvement within the first six months (two percent did not 
respond). Among driver types, long-haul drivers revealed the greatest 
improvement, with 38 percent indicating that the 2003 rule helped them 
establish and maintain a 24-hour cycle, while 30 percent of short-haul 
drivers indicated that the 2003 rule helped them to establish and 
maintain a 24-hour cycle.
    In response to the question, ``Do you get more time at home under 
the new HOS regs regime?'' 20 percent felt they did in fact get more 
time at home as a result of the 2003 rule, while 77 percent indicated 
they experienced no increase

[[Page 50002]]

within the first six months (two percent did not respond). In response 
to this question, regional drivers reported the greatest improvement 
(22 percent), followed by long-haul drivers (21 percent), and then 
short-haul drivers (18 percent).
    To the question, ``Do the new HOS regs allow you to get more rest 
and therefore reduce your level of fatigue?'' 29 percent of driver 
respondents replied the 2003 rule did in fact allow them to get more 
rest, while 60 percent indicated no improvement in rest time within the 
first six months. Regarding the second part of this question, 14 
percent of respondents indicated that they never had fatigue. To this 
last question, long-haul drivers indicated the greatest improvement. 
Thirty-two percent received more time at home and felt less fatigued 
under the 2003 rule. Twenty-three percent of short-haul drivers felt 
that they received more time at home and therefore felt less fatigued 
under the 2003 rule. Driver responses to the complete set of OOIDA 
survey questions can be found in the docket.

I.3. Burks' Private Carrier Survey

    Dr. Stephen Burks of the University of Minnesota, Morris, conducted 
a survey of private fleets in 2004 to determine the percentage of runs 
that utilized the three major provisions of the 2003 rule; namely, the 
11th hour of driving, 34-hour recovery, and split sleeper berth. 
Additionally, several other operations-related questions were posed. A 
total of 31 firms responded to the survey, representing a total of 
7,115 power units and 30.3 million miles traveled during the month of 
June 2004. The average run for this group of respondents was 537 miles, 
with a minimum reported run of 41 miles and a maximum reported run of 
2600 miles. A more detailed summary of these survey results is included 
in the docket.
    Results indicate that the 34-hour recovery period is the provision 
most used by private firms responding to this survey. The 34-hour 
recovery period was used on average in 61 percent of the respondents' 
runs. This does not necessarily mean, however, that all recovery 
periods utilized the minimum 34 hours recovery. In fact, as was seen in 
the FMCSA Field Survey, many drivers took more than the minimum 
required 34 hours off duty. The 11th hour of driving and split sleeper 
berth were used less often, according to Burks' survey. The 11th hour 
of daily driving was used on average in 31 percent of runs, while the 
split sleeper berth was used on 26 percent of runs.
    The above percentages are averages, so there is variation among 
firms in the use of the provisions. Some private firms indicated they 
used each of these provisions on 100 percent of their runs, while 
others indicated that they never used them. As a result, when reporting 
mean values, any extreme outliers on either side can skew the results. 
Thus, the data may be better understood by examining the median value 
of responses to each of these questions, or the point at which half of 
the survey respondents indicated less use of a particular provision and 
half indicated more.
    The median for the 34-hour recovery provision was 85 percent, 
indicating that half of survey respondents used the provision in fewer 
than 85 percent of its runs, while the other half used it in more than 
85 percent of its runs (by ``run,'' it is assumed the researchers were 
referring to a firm's weekly runs when discussing the 34-hour recovery 
provision). Reporting the median value for the 34-hour recovery seems 
to validate the relatively high mean value reported earlier (61 
percent), in that private firms appear to be utilizing this provision 
quite extensively. Regarding the 11th hour of daily driving, the median 
was 10 percent, indicating that half the firms surveyed used it in 
fewer than 10 percent of runs, while the other half used it in more 
than 10 percent. With regard to split sleeper berth, the median value 
was 2 percent. Thus, the median values for the 11th hour of daily 
driving and split sleeper berth indicate low usage of these provisions, 
respectively, by private firms responding to this survey.

I.4. Schneider National

    At the Annual Conference of the Transportation Research Board 
(TRB), held in January 2005, in Washington, DC, a session was entitled, 
``Truck Drivers Hours-of-Service: One Year Later.'' As part of this 
session, Mr. Donald Osterberg, a representative from Schneider 
National, Inc., one of the largest for-hire trucking companies, 
presented information on his company's experience under the 2003 HOS 
rule. During this presentation, Mr. Osterberg noted that roughly 10 
percent of the Schneider fleet used the 11th hour of daily driving 
during the months of June and October 2004. The portion of the 
Schneider drivers using a sleeper berth to split their minimum 10-hour 
daily off-duty periods was 6 percent in early 2004, falling to roughly 
2 percent in June of 2004, and falling further to fewer than 0.5 
percent of drivers in October 2004. Also, Mr. Osterberg noted that 
between 26 and 32 percent of Schneider drivers used the recovery 
provision to take between 34 and 44 hours off between weekly on-duty 
periods. These results are consistent with those found in the FMCSA 
Field Survey discussed earlier. Mr. Osterberg's statements were 
supported by data provided upon request in a handout to FMCSA after the 
session. This handout consisted of various summary calculations of 
logbook entries pulled for the months of June and October 2004. These 
summaries are in the docket.
    Regarding commercial drivers' current use of the most important 
provisions from the 2003 rule, a summary of responses from the 
aforementioned data sources is contained in Figure 6.

  Figure 6.--Summary of Survey Information, Carrier/Driver Use of 11th Hour of Daily Driving, 34-Hour Recovery
                                    Period, and Split Sleeper Berth Exemption
----------------------------------------------------------------------------------------------------------------
                                                          Percent of runs (daily or weekly) using HOS provision
                                                        --------------------------------------------------------
                                                                                                 Split sleeper
                      Date source                        11th driving hour   34-hour recovery  berth (daily runs
                                                         (daily runs or on-  (weekly runs or       or on-duty
                                                           duty periods)     on-duty periods)       periods)
----------------------------------------------------------------------------------------------------------------
FMCSA Survey...........................................                 21             \1\ 73            \2\ N/P
OOIDA Survey...........................................                 28                 80                 13
Burks Survey...........................................                 31                 61                 26
Schneider National Logbook Summary.....................             \1\ 10            \2\ N/P          \1\ .05-6
----------------------------------------------------------------------------------------------------------------
\1\ Percent of drivers (not daily or weekly on-duty periods).
\2\ Not provided (NP) because of how the survey data were compiled and/or how they were reported publicly.


[[Page 50003]]

I.5. Virginia Tech Transportation Institute Study

    An analysis was conducted of data collected from an ongoing FMCSA-
NHTSA sponsored Field Operational Test of a Drowsy Driver Warning 
System. This on-the-road driving study, performed by Virginia Tech 
Transportation Institute (VTTI), began collecting data in May 2004. All 
data collected through May 1, 2005 were used in the current analysis 
[Hanowski, R.J., et al. (2005)]. In all, operational data were 
collected and analyzed from 82 CMV drivers working for one of three 
licensed trucking companies.
    Preliminary results from this study reveal some interesting 
patterns concerning sleep duration. The results, based on 1,736 days of 
data for 73 drivers, show a mean daily sleep time of 6.28 hours with a 
standard deviation of 1.4 hours. Data collected from 80 truck drivers 
under the pre-2003 rule and with different driving schedules, found 
``drivers averaged 5.18 hours in bed per day and 4.78 hours of 
electrophysiologically verified sleep per day over the five-day study 
(range, 3.83 hours of sleep . . . to 5.38 hours of sleep)'' [Mitler, 
M.M., et al. (1997), p. 755].
    The ``hours in bed'' value from Mitler, et al. is a comparable 
measure to the mean hours of sleep value resulting from this new study. 
A study of long-haul drivers [Dingus, T., et al. (2002), p. 205] found 
self-reported sleep per night for single drivers, while on the road, to 
be approximately 5.8 hours. This study was conducted under the pre-2003 
rule. The VTTI study also used single drivers (i.e., no teams); 
consequently, the Dingus et al. study can serve as another reference 
point to compare results.
    In summary, preliminary results from the VTTI study have found 
drivers are sleeping considerably more (up to 1.5 additional hours per 
night on average) under the 2003 rule than either the Mitler et al. 
study or the Dingus et al. study found under the pre-2003 rule. One 
rationale for instituting the 2003 rule was to provide drivers with 
additional time off to provide more opportunity to obtain sufficient 
sleep. Based on the results of the Virginia Tech Study to-date, drivers 
appear to be getting more sleep per night on average, compared to data 
collected from drivers under the pre-2003 HOS regulations [Mitler, M. 
M., et al. (1997); Dingus, T., et al. (2002)].

J. Comments to Docket and FMCSA Response

    Between January 24, 2005, and April 5, 2005, FMCSA received 1,790 
comments from approximately 1,590 commenters on the 2005 NPRM. Figure 7 
shows the number of comments by type of submitter. The number of 
comments, particularly for drivers, is greater than the number of 
individual commenters because some submitted multiple documents, 
answering in separate submissions each of the questions FMCSA posed.

                 Figure 7.--Number of Commenters by Type
------------------------------------------------------------------------
                                                               Number of
                        Commenter type                          comments
------------------------------------------------------------------------
Trucking Associations........................................         20
Safety Advocacy Groups.......................................          9
Other Associations...........................................         31
Law Enforcement..............................................          4
Unions.......................................................          3
Carriers.....................................................        223
Drivers: Long Haul...........................................        312
Drivers: Short Haul..........................................         42
Drivers: Not otherwise specified.............................      1,010
Other Industries.............................................         57
Others.......................................................         79
                                                              ----------
  Total......................................................      1,790
------------------------------------------------------------------------

    Of the carriers submitting comment letters, 203 letters were from 
for-hire firms and only 20 from private carriers; 112 identified 
themselves as long-haul carriers and 30 as short haul; 71 described 
themselves as owner-operators. It is likely that some of those 
classified as drivers are owner-operators, but unless they specifically 
stated that, they were not classified in that group. The ``Others'' 
group includes private citizens, a few third-party vendors, and one 
academic researcher; most of the private citizens may be drivers, but 
did not state that or provide a clear indication that identified them 
as drivers.
    The following issue sections provide further details regarding 
comments submitted to this docket. Although issues are discussed one at 
a time, the Agency stresses that the proper focus is on their joint 
effects and on the resulting response. Section J.11 discusses the 
combination more directly.

J.1. Sleep Loss

    In the 2005 NPRM, FMCSA requested information on both the 
beneficial and adverse effects of the 2003 rule on the health of CMV 
drivers, and expressed particular interest in information about any 
increase or reduction in sleep deprivation generated as a consequence 
of the 2003 rule. How much sleep do drivers operating under the new 
regulations average on a daily basis, the Agency asked, and how has 
this average changed as a result of the 2003 HOS rule.
    One hundred thirty-four commenters, primarily drivers, responded to 
the question. Twenty-nine said that the 2003 rule made no difference to 
the amount of sleep they obtained, but 60 said they obtained more sleep 
under the new rule.
    The Insurance Institute for Highway Safety (IIHS) reported that a 
survey it had conducted found that there was a ``slight increase in the 
percentage of drivers (from 40 percent in 2003 to 42 percent in 2004) 
who said they had driven while sleepy at least once in the past week.'' 
The percentage of drivers who reported actually dozing at the truck 
wheel on at least one occasion in the past month was 13 percent in 2003 
and 15 percent in 2004.
FMCSA Response
    When asked about the amount of sleep drivers were getting with 
regard to the 2003 rule and specifically the 10 consecutive hours off-
duty provision, commenters confirm that drivers are in fact obtaining 
more rest today than under the pre-2003 HOS rule. An OOIDA survey 
referenced in Section I.2 and a joint NHTSA/FMCSA study referenced in 
Section I.5 of this preamble add additional support for this 
conclusion.
    IIHS' data regarding drivers dozing while driving is not supported 
by current crash data; the data suggest that the number of fatigue 
crashes have decreased in the first 9 months of 2004 (43 fatigue 
crashes) compared to the first 9 months of 2003 (54). Therefore, even 
if the IIHS data is accurate and statistically significant, the dozing 
behavior does not appear to be relating to an increase in fatigue-
related crashes. It is difficult to comment without knowing all of the 
details regarding the IIHS survey. However, based on the Agency's 
experience, one would expect that a two percentage point increase in 
reported dozing could be a function of sampling error and statistically 
insignificant.

J.2. Exposure to Environmental Stressors

    FMCSA requested comments on how the 2003 rule, and in particular 
the extension of driving time from 10 to 11 hours and the shortened 
driving window created by the 14-hour limit, would affect a driver's 
exposure to environmental stressors, such as vehicle noise, vibration, 
and emissions.
    Fifty-nine commenters, including 13 carriers, 44 drivers, one law 
enforcement organization, and one private citizen, responded that the 
2003 HOS rule had little or no effect on

[[Page 50004]]

exposure to environmental stressors. They stated that modern truck 
technology has reduced vibration, noise levels, and emissions and that 
the consequences of any additional driving time were either offset by 
the workday restriction, or insignificant. ATA commented that potential 
driver exposure to diesel exhaust (DE) has decreased to a point below 
both Environmental Protection Agency (EPA) and OSHA requirements, and 
will probably further improve. ATA included tables illustrating the 
improvements. One carrier commented that more stringent regulations, 
improvements in technology and road conditions, and better maintenance 
practices had reduced environmental stressors.
    ATA commented that modern truck cabs are much quieter, far quieter 
than the maximum requirement, are well ventilated, and have well 
designed, efficient heating and air conditioning units. Physical stress 
on drivers, including road vibration, is reduced by power steering. 
Many trucks are also equipped with automatic transmissions, further 
reducing stress. Improved suspension gives the driver a better ride, 
and provides better handling. The comfort and safety improvements in 
truck tractors improve the driver's conditions, leading to a reduction 
in stress and fatigue; and operators could drive an additional hour, 
``yet be safer than drivers in the past.'' Two carriers also commented 
that modern trucks have greatly reduced noise and vibration. One 
carrier said that due to the lack of vibration, the quality of sleep in 
a new truck is ``great,'' while another wrote that drivers become less 
fatigued in the improved trucks.
    In contrast to the commenters who identified little or no exposure 
to environmental stressors, Public Citizen, Advocates for Highway and 
Auto Safety (AHAS), and the National Institute for Occupational Safety 
and Health (NIOSH) responded with extensive summaries and citations of 
current research applicable to the question of exposure to 
environmental stressors.
    Public Citizen stated that the largest source of diesel emissions 
is diesel-powered ``big-rigs,'' and other highway diesel vehicles. 
Truck drivers are constantly exposed to DE fumes, ``waiting for a load, 
stopping at a truck stop, or operating the truck.'' The long-term 
effect of breathing DE and other chemicals poses a significant 
potential source of risk for truck drivers, Public Citizen argued, 
providing numerous citations of articles and studies relating 
particularly to the health impacts of DE. It pointed out that while 
FMCSA expected that EPA emissions standards would result in a 
significant reduction in emissions from new diesel vehicles beginning 
in 2007, current, unmodified, diesel powered trucks would probably be 
operating through the 2030s. Public Citizen cited a report recently 
released by the Clean Air Task Force (CATF), of which Public Citizen is 
a supporting member, highlighting the toxicity of diesel emissions and 
numerous acute health risks associated with exposure to diesel 
emissions. Public Citizen concluded that ``Diesel particulate matter is 
well established as a probable carcinogen. * * * Moreover, fine 
particles have been documented by literally thousands of studies as 
associated with respiratory and cardiovascular diseases as well as 
premature mortality.''
    Public Citizen disagreed with FMCSA that the impact of a one-hour 
increase in driving hours is unclear. Arguing that the 2003 HOS rule 
allowed an increase of more than 600 annual driving hours over the pre-
2003 rule, Public Citizen stated that this increase represented 
hundreds of additional hours per year when truckers would be exposed to 
elevated levels of DE fumes. They concluded that ``A robust body of 
evidence indicates that the exhaust[s] are highly toxic and tied to a 
multitude of health risks, and therefore it is negligent of FMCSA to 
promulgate an hours of service rule that so significantly increases 
drivers' exposure to these fumes.''
    AHAS criticized FMCSA for using in the 2005 NPRM almost exclusively 
studies that dealt only with commercial drivers, arguing that much 
relevant research literature existed in other work-related areas such 
as shift work fatigue and performance failures. AHAS provided numerous 
citations for studies that it regards as providing directly relevant 
findings from other occupational areas. AHAS asserted that FMCSA 
ignored relevant research, which it cited, from EPA and others that 
conclude that chronic DE inhalation exposure might be a cancer hazard 
for humans. AHAS also provided an extensive list of studies in the 
field of occupationally related whole-body vibration, and asserted that 
FMCSA had not included the most relevant studies in the docket.
    AHAS listed and summarized numerous studies addressing the 
psychological and physiological effects of long working hours, 
irregular shiftwork, and accumulated sleep debt, and provided lists of 
sources of statistics and analysis on injuries and illnesses, including 
psychological disorders, digestive disturbances, headaches, high blood 
pressure, anxiety, gastrointestinal diseases, and reproductive 
dysfunction that it considered potentially affecting truck drivers.
    NIOSH commented extensively on the issue of driver exposure to 
diesel fuel exhaust and other vehicle emissions. NIOSH conceded that 
assessing driver exposure to vehicle exhaust is complicated because of 
the variety of possible exposure scenarios, including driving, sitting 
in the cab, or working at a loading dock. NIOSH noted that few exposure 
assessments of commercial drivers had been conducted prior to the 2003 
HOS rule and none have been conducted since. NIOSH reported that 
current research indicates that some health risks from DE are 
associated with particulate matter (PM) in emissions. EPA emissions 
standards have led to cleaner burning diesel fuel, and newer engines 
produce less PM. NIOSH wrote that DE particles increase allergic 
responses, and might lead to harmful structural changes in the airways, 
and that there is an association between PM and cardiovascular and 
respiratory morbidity and mortality.
FMCSA Response
    Most, if not all, of the concerns raised by commenters regarding 
driver health have been evaluated and are addressed earlier in this 
preamble. FMCSA notes that the majority of commenters, particularly 
drivers, stated that the rule will have little or no impact on driver 
health. The Agency agrees with ATA's assessment that modern truck 
technology has reduced vibration, noise levels, and exposure to DE, and 
that the consequences of any additional driving time are either offset 
by the workday restriction, or insignificant.
    Public Citizen and AHAS cited a number of studies that found an 
association between DE and cancer. The TRB driver health team reviewed 
these studies and selected studies relevant to this rulemaking to be 
summarized for the driver health evaluation discussed earlier in this 
preamble. The standards for inclusion were the validity of the 
methodology, the relevance of the studied population to truck driving 
and the quality of the statistical analysis of health outcomes. FMCSA 
has reviewed the research and does not dismiss the association; 
however, there have been significant changes in diesel engine design, 
changes in emissions standards, and changes in emission types and 
composition, which make many of these studies inapplicable to today's 
environment. EPA has stated there is considerable uncertainty about 
whether ``health hazards identified from previous studies using 
emissions from

[[Page 50005]]

older engines can be applied to present-day environmental emissions and 
related exposures, as some physical and chemical characteristics of the 
emissions from certain sources have changed over time. Available data 
are not sufficient to provide definitive answers to this question 
because changes in DE composition over time cannot be confidently 
quantified, and the relationship between the DE components and the 
mode(s) of action for DE toxicity is unclear'' [Ris, C. (2003), p. 33].
    Public Citizen commented that the largest source of diesel 
emissions is from heavy vehicles. While that is true, DE is only one 
contributor to a complex pollution mixture, and there are many other 
combustion sources. DE from heavy vehicles represents only 23 percent 
of all emissions from all mobile sources. EPA models show that vehicle 
emissions from all mobile sources have declined significantly from 1990 
to 2005 (average 35 percent reduction in emissions). DE has also 
declined 55 percent from 1990 to 2005 and it is projected to decline an 
additional 88 percent by 2030. Therefore, drivers are being exposed to 
less pollution than they were in the early 1990s when accurate data 
first became available.
    Further, any health risk associated with DE will continue to 
diminish with planned changes in standards for diesel fuel and engines. 
EPA projections are based on estimates of vehicle miles traveled and 
new vehicles entering and old vehicles leaving the inventory, and 
reflect changes in vehicle emissions standards. Reductions in diesel 
particulate matter are occurring now; these are not reductions that 
will be seen in the next generation of diesel engines. The CATF study 
supported by Public Citizen argues that the Federal government needs to 
cut DE further and retrofit existing trucks to further reduce DE. 
However, as shown the mainstream research community has not 
quantitatively determined a precise dose-response relationship between 
DE and cancer. In fact, DE at current ambient environmental levels is 
not thought to be predictive of cancer; testing on rats at 
environmental levels has not led to the development of cancer [Id., p. 
35]. EPA has stated ``the DE exposure-response data for humans are 
considered too uncertain to derive a confident quantitative estimate of 
cancer unit risk, and with the chronic rat inhalation studies not being 
predictive for environmental levels of exposure, EPA has not developed 
a quantitative estimate of cancer unit risk'' [Id., p. 36]. 
Additionally, the CATF study is based on some unrealistic and 
misleading assumptions. The study suggests that heavy trucks will 
remain in the inventory for more than 30 years; therefore changes in 
EPA standards will have little effect for many years [Schneider, C. G., 
& Hill, L.B. (2005), p. 8]. FMCSA analysis of commercial vehicle 
registration data from Polk & Co., a proprietary data collection firm, 
found that fewer than 50 percent of 2004 registered vehicles (Large 
Trucks over 26,001 GVWR) were greater than 10 years old and 87 percent 
were less than 20 years old. This means that the data being quoted in 
the CATF study are from a model that does not appear to be accurate--
the productive life of a CMV is far less than 30 years. Potentially, 
this flaw could have dramatic changes in the predications regarding DE.
    In addition, comments from Public Citizen, AHAS, and others 
regarding the increased health risk due to DE exposure are all 
predicated on the assumption that drivers are working more hours as a 
result of the 2003 HOS rule. A drastic increase in driving or on-duty 
time under that rule is impossible to reconcile with economic reality. 
The U.S. economy has been expanding strongly for some time, creating 
renewed demand for trucking services and a steady increase in vehicle 
miles traveled. But there has been no quantum leap in economic activity 
that would demand or support the greatly extended driving hours 
asserted by these commenters. Federal Highway Administration data show 
that the vehicle miles traveled (VMT) by all trucks increased by 26.03 
percent between 1994 and 2002, the last year for which complete 
statistics are available. That works out to an average VMT increase of 
2.89 percent per year [calculated from http://www.fhwa.dot.gov/policy/ohpi/qftravel.htm
]. The theoretical availability of many more driving and 

on-duty hours under the 2003 rule is largely irrelevant. Truckers drive 
to meet the demand for transportation, and VMT statistics show that 
demand increases (and occasionally decreases) in modest annual 
increments. Most of the additional demand is satisfied by adding new 
trucks and drivers to the motor carrier industry. The Agency has not 
found any data that suggests drivers are actually working significantly 
longer hours. Therefore, in the Agency's best judgment, drivers are not 
exposed to increased health risk as a result of the 2003 or today's 
rule.

J.3. Workplace Injuries and Fatalities

    The 2005 NPRM requested comments about the impact of fatigue and 
loss of alertness on CMV driver workplace injuries and fatalities, and 
any evidence connecting workplace injuries and fatalities to specific 
aspects of the 2003 rule or previous HOS regulations. FMCSA explained 
that it was interested only in injuries directly related to the HOS 
regulations and operating a CMV, not other workplace injuries that are 
outside its jurisdiction.
    Twenty-eight commenters said that the 2003 rule does not have an 
impact on workplace injuries. One carrier, B.R. Williams Trucking, 
which had reviewed the company's workplace injuries, stated that there 
had been neither an adverse nor a positive change related to the rule. 
Work schedules, hours driving, and hours off duty did not affect the 
company's injury rate.
    Twenty-seven commenters expressed other views about workplace 
injuries and fatalities. Nearly all of them agreed that fatigue and 
loss of alertness can be a contributing factor, but some commenters 
pointed out that the amount of the contribution varies from one 
individual to another. One commenter suggested that injury and fatality 
statistics should be broken out by type of operation.
    Other commenters were uncertain about the impact of the rule. Four 
thought the rule gave drivers more rest and limited their hours of 
work, so crashes and injuries should be reduced. Six mentioned data 
indicating that injuries had decreased in recent years, but they said 
those decreases were not necessarily attributable to the 2003 rule. 
Four believed the rule's lack of flexibility, the extra hour of driving 
allowed, or the inability to stop the 14-hour clock, could contribute 
to fatigue and lead to more crashes. Five commenters pointed out that 
many drivers' injuries occur when they are loading or unloading and 
said that drivers should not be required or allowed to perform these 
activities.
    Public Citizen asserted the rule has a direct effect on injuries, 
and accused the 2005 NPRM of suggesting groundless limitations on 
FMCSA's legal responsibility to address them in the rule. For example, 
they stated that the ``Workplace Injuries and Fatalities'' section of 
the NPRM drew an ``unsupportable'' distinction between injuries 
relating directly to the HOS regulations and operating a CMV, and other 
workplace injuries and environmental stressors, such as loading and 
unloading. Rejecting the Agency's position, Public Citizen cited 
several FMCSA reports, technical analyses, and literature reviews that 
assessed non-driving issues, including loading and unloading, sleep 
apnea, and physical activity and their impacts.

[[Page 50006]]

    Many commenters suggested workplace injuries and illnesses have 
decreased in 2004. The Motor Freight Carriers Association (MFCA) asked 
its membership to provide data and information regarding workplace 
injuries. MFCA's preliminary analysis of that data suggests that 
injuries and fatalities have decreased in 2004. They commented that 
``while we are encouraged by these findings, it would be premature to 
attribute the results singularly to the change in hours of service 
rules.'' FedEx commented that ``in their pick up and delivery and their 
short and long haul divisions combined, there was a 5.44 percent 
reduction in injuries even with a 2.2 percent increase in hours worked 
for all employees.'' FedEx Freight reports the overall injury and 
illness rates for its driver population decreased by almost 4 percent 
from 2003 to 2004. Landstar Systems, Inc. commented that it had 
experienced 8.6 percent fewer on the job injuries with the 2003 HOS 
rule. Maverick Transportation, Inc. commented that it does not track 
injuries by loading/unloading, but the total number of injuries 
experienced by its drivers in 2004 decreased by 19 percent and crash-
related injuries decreased by 30 percent compared to 2003. J.B. Hunt 
commented that it has on-going safety initiatives concurrent with the 
hours-of-service changes, so it is difficult to independently conclude 
that any changes in injuries are attributable to a single factor. J.B. 
Hunt reported that it experienced a 19 percent reduction in injuries 
categorized as ``driving/riding'' from 2003 to 2004. The carrier also 
found that injuries related to getting in and out of the truck declined 
by 18 percent.
FMCSA Response
    The Agency agrees with ATA's assertion that the occupational injury 
and illness record of the trucking transportation industry has improved 
in the last five years. U.S. Bureau of Labor Statistics (BLS) data show 
that there have been significant reductions in workplace illness and 
injuries in the trucking industry--the number of nonfatal occupational 
injuries and illnesses involving days away from work has decreased from 
152,803 in 1996 to 129,068 in 2001, a 16 percent decrease. Although the 
industrial categories changed slightly in 2003, the number of nonfatal 
occupational injuries and illnesses for truck drivers decreased 31 
percent between 1996 and 2003.
    BLS statistics for 2004 are currently being collected and analyzed 
and will not be available until November 2005. For this reason FMCSA 
requested data from the public in the 2005 NPRM regarding 2004 
workplace injury and illnesses.
    Many commenters cited data that showed that workplace injuries and 
illness have decreased in 2004. The Agency recognizes these comments 
are not a representative sample of the whole industry; however, FMCSA 
is encouraged that the information provided suggests that workplace 
injuries and illness appear to have decreased from 2003 to 2004. No 
commenters have suggested that injuries and illness have increased 
solely as a result of the 2003 HOS rule; nor does FMCSA.
    Many commenters, particularly drivers, said that they did not see 
the connection between the HOS regulation and workplace injuries and 
illness. The Agency, based on its experience, however, believes that 
there clearly is a connection between driver fatigue and alertness. 
Further, one driver responded that ``the loss of alertness or fatigue 
affects a truck driver's ability to focus and judge distances causing 
crashes. These crashes are less prevalent under the new HOS because a 
driver gets more rest under these rules than under the old rules.''
    Public Citizen asserted that the NPRM drew an ``unsupportable'' 
distinction between injuries relating to HOS regulations and other 
workplace injuries, which are outside the jurisdiction of the Agency. 
``FMCSA expressly distinguishes injuries and fatalities relating to 
workplace hazards such as loading and unloading.'' The NPRM stated that 
FMCSA did not intend to focus on workplace injuries caused by 
conditions beyond the jurisdiction of the Agency [70 FR 3345], e.g., 
falling down a staircase at a motor carrier terminal because a step was 
loose. OSHA has the authority to regulate that kind of threat to 
workplace safety. Public Citizen seems to assume that fatigue is an 
element in many non-driving accidents suffered by drivers, and that the 
HOS rule is therefore a ``major contributing factor'' to such mishaps.
    FMCSA did not deny that drivers engaged in loading or unloading are 
subject to the HOS regulations; the 60- or 70-hour clock continues to 
run while drivers handle cargo. The Agency simply directed commenters' 
attention to injuries that are immediately related to the HOS 
regulations and away from loading or unloading injuries that might be 
caused by any number of other factors completely unrelated to HOS, such 
as shifting cargo, broken securement straps, inadequate packaging, 
incorrectly marked loads, poorly maintained forklifts, or slippery 
loading dock surfaces. Public Citizen concluded that ``FMCSA may not 
limit its statutory responsibility to driver health for only the period 
when a trucker is driving.'' FMCSA has not attempted to confine its 
responsibility to driving time. The Motor Carrier Safety Act of 1984, 
however, requires only that ``the [Agency's] regulations * * * ensure 
that * * * the operation of commercial motor vehicles does not have a 
deleterious effect on the physical condition of the operators' [49 
U.S.C. 31136(a)(4)]. FMCSA is not, and cannot be, responsible for every 
physical infirmity experienced by truck drivers. There are many threats 
to health and safety in the modern world, and most of them have nothing 
to do with the HOS regulations. The NPRM concentrated on matters the 
Agency can address.

J.4. Lifestyle Choices

    In the 2005 NPRM, FMCSA noted that lifestyle choices, including 
diet and exercise, may impact driver health and safety, but also 
concluded that ``Realistically, such choices cannot be regulated by 
FMCSA.'' The Agency requested commenters to provide information on the 
effect lifestyle choices, such as diet, exercise, and the use of off-
duty time, have on driver safety and health.
    Only 36 commenters responded to this request; all appeared to agree 
that proper diet and exercise are important elements in maintaining 
driver health, but two or three commenters were less certain about the 
effect of lifestyle choices on safety. Ten of the commenters insisted 
that healthy options are difficult to find on the road, and they were 
particularly critical of fast-food meals at truck stops and the lack of 
exercise facilities.
    Ten commenters argued that lifestyle choices are individual 
decisions and cannot be regulated by the HOS rule, except to the extent 
the rule provides an opportunity for healthy choices and sufficient 
off-duty time. Three commenters approved of the additional off-duty 
time provided by the 2003 rule, but others thought the 14-hour 
provision made it difficult to maintain a proper diet. One commenter 
believed that too much off-duty time had a negative effect. Two 
commenters suggested that private-sector training is a more effective 
method of helping drivers with lifestyle choices than HOS requirements. 
Two other commenters mentioned FMCSA rules that require medical 
screening and monitoring for drivers and pointed out that those rules

[[Page 50007]]

already encourage drivers to maintain healthy habits.
    Public Citizen, however, alleged the NPRM's ``Lifestyle Choices'' 
discussion was illegitimate and a disingenuous attempt to narrow 
FMCSA's oversight of driver health. In the opinion of this commenter, 
the HOS rule had significant potential to influence a driver's diet and 
exercise regime, which in turn could greatly influence an individual's 
bodyweight, blood pressure, and other health indicators. The commenter 
provided no research or data to support this assertion.
    With regard to lifestyle choices and their effect on driver 
fatigue, Express Inc. commented that its ``experience indicates the 
lifestyle decisions made by a driver prior to getting behind the wheel 
as well as decisions made while on the road, are by far the most 
significant factors in fatigue related accidents.'' Additionally, FedEx 
stated that ``lifestyle choices, more than anything else, have the 
greatest impact on fatigue related accidents. Without question, the 
lifestyle choices drivers make during their off duty time are extremely 
significant. Coupled with decisions made on-duty during a trip, they 
are the most critical choices relating to fatigue prevention.'' Lastly, 
with regard to drivers meeting FMCSA medical requirements, Brink Farms 
noted that ``FMCSA can't regulate driver's lifestyle choices, but 
regulating their blood pressure levels is regulating driver's health. 
Many of our drivers have had to change their lifestyle due to higher 
blood pressure than allowed by these limits. Many of our drivers have 
begun walking more, and watching their diet more. Exercise alone keeps 
a driver healthier and that also keeps them more alert.''
FMCSA Response
    The Agency included questions on this issue in the NPRM because 
lifestyle choices appear far more likely to directly affect driver 
health than many of the occupational and environmental factors faced by 
CMV drivers.
    Roberts and York (1997) conducted a study for FMCSA entitled 
``Design, Development and Evaluation of Driver Wellness Programs.'' 
They cited a number of areas where drivers make poor lifestyles 
choices, for instance by smoking. The percentage of smokers among truck 
drivers is nearly double that of the U.S. population. A 1993 study of 
2,945 truck drivers reported 54 percent of the respondents smoke 
cigarettes or cigars [Roberts, S., & York, J. (1997), p. I-2]. In 
contrast, national statistics in 1996 showed that 27.7 percent of all 
males and 25 percent of all men and women were smokers [Id.]. The use 
of tobacco products is the leading preventable cause of death in the 
United States. Smoking substantially increases the risk of 
cardiovascular disease, causes about 30 percent of all cancer deaths, 
and is the leading cause of chronic lung disease [Id., p. I-1]. Truck 
drivers who smoke in their cabs are perhaps at even greater risk of 
developing illnesses. They can get a double dose of toxins by inhaling 
smoke directly from the cigarette or cigar and by breathing in any 
second-hand smoke that remains inside the cab.
    A significantly higher percent of CMV drivers were classified as 
obese compared to the population in general [Id., p. I-2]. Of 2,945 
truck drivers at a trade show, 73 percent were classified as being 
either overweight or obese. Of these drivers, 33 percent were 
classified as obese (i.e., Body Mass Index Greater than 30) and 40 
percent were classified as overweight (i.e., Body Mass Index between 25 
and 30) [Id.]. Nationally, only 33 percent of men and women combined 
are classified as being overweight [Id., p. I-3]. In the research 
literature, obesity is a well-established risk factor for many diseases 
such as stroke, cardiovascular disease, hypertension, and diabetes. It 
also exacerbates problems with conditions such as arthritis or back 
pain. Evidence also suggests that obesity, in conjunction with other 
risk factors, places men and women at a higher risk of cancer [Id., p. 
I-2].
    Roberts and York [Id., p. I-8) identified the prevalence of poor 
eating habits among CMV drivers. A 1993 study of 2,945 truck drivers 
revealed over 80 percent of these drivers ate only one or two meals per 
day and 36 percent had three or more snacks per day [Id., p. I-6]. 
Furthermore, a 1996 study of 30 drivers in a wellness program revealed 
that their favorite meal item while on the road was steak or burgers 
and typical snacks were chips, fruit, candy, donuts, and cookies. Only 
15 percent of these drivers ate five or more servings of fruits and 
vegetables per day, compared to 19.1 percent of all males.
    CMV drivers are more likely to be inactive or underactive as 
compared to the population in general [Id., p. I-7]. Despite the 
importance of regular exercise to disease prevention and health, 50 
percent of the truck drivers in a 1993 study never participated in any 
type of aerobic exercise and only 8 percent of these drivers 
``regularly'' participated in aerobic exercise [Id.]. The 1997 National 
Health Interview Survey showed 60 percent of adults do engage in 
physical activity for at least 20 minutes per day. Both epidemiological 
evidence and medical research demonstrate the ability of physical 
activity to reduce the risk of many physiological diseases, including 
heart disease, high blood pressure, osteoporosis, diabetes, and breast 
and colon cancer, as well as reduce the risk of psychological illnesses 
such as depression, anxiety, and stress [Id.].
    On three important lifestyle variables, CMV drivers rank well below 
average. CMV drivers smoke tobacco at nearly twice the rate of the U.S. 
population, have questionable eating habits, and do not exercise 
regularly. As a result, twice as many CMV drivers are overweight 
compared to the U.S. population. These lifestyle choices are bound to 
have profound effects on the health and wellness of CMV drivers, and in 
the Agency's best judgment may, by themselves, be predictive of higher 
rates of cancer, cardiovascular disease, diabetes, and back problems.

J.5. Driving Time

    FMCSA solicited comments in the NPRM on the impacts of incremental 
increases in driving time on driver health, the safe operation of CMVs, 
and industry economics. In particular, it asked, to what extent did the 
increase in maximum driving time from 10 to 11 hours affect health, 
safety, and economic factors?
Support for 11-Hour Limit
    The majority of commenters (208 out of 360 or 58 percent) who 
expressed opinions on the 11-hour driving rule supported it, including 
the American Trucking Associations (ATA), the Truckload Carriers 
Association (TCA), the Owner-Operator Independent Drivers Association 
(OOIDA), and the National Private Truck Council (NPTC).
    In all, six trucking associations expressed support for the 11-hour 
driving limit. ATA agreed with the 11-hour limit and said that it 
should be retained. However, ATA also acknowledged that the 
establishment of any driving time limit would benefit from continued 
fatigue-related research. TCA stated that the limited scientific data 
available did not show a significant distinction between 10- and 11-
hour drive times. NPTC said that the 11-hour limit had improved the 
quality of drivers' rest by allowing drivers to make it all the way 
home and sleep in their own beds. NPTC said that if FMCSA reverted to a 
10-hour limit, the drivers would have to forego returning to home each 
evening, or the company would have to schedule additional drivers and 
shipments.
    The National Industrial Transportation League (NITL) said that

[[Page 50008]]

the additional hour of driving is warranted and justified in light of 
the amount of rest that drivers obtain under the 10-hour off-duty 
requirement. NITL said that the additional hour of driving time 
increases driver and asset productivity, and, in the aggregate, reduces 
the need to bring additional trucks onto the roads, which translates 
into fewer accidents. The National Armored Car Association (NACA) said 
that the 11-hour limit is appropriate and reduces risk to the drivers 
of armored cars, who are not allowed to pull off to the side of a road 
or stop overnight at a motel as they approach permissible workday 
limits, because of the risk of crime. NACA said that the additional 
hour provides a margin of safety for responding to such contingencies.
    Five other carriers also provided substantive comments supporting 
the 11-hour driving limit. The carriers said that the one-hour increase 
in the daily driving limit has benefited them economically without 
having any detrimental impact on safety. Two of the carriers said their 
drivers had benefited from the 11-hour driving limit. ABF Freight said 
that some of its drivers who performed defined runs that required close 
to ten full hours of driving reported feeling less stress under the 11-
hour driving limit. Crete Carrier Corporation said that its operation 
cycles indicated that its drivers' work and sleep patterns had begun to 
benefit from the 2003 rule. The carrier said that its drivers appeared 
to have adjusted their driving routines to more closely resemble the 
traditional workday. The carrier also said that it had teamed with 
shippers and consignees to schedule pick-up and delivery times that 
were more consistent with drivers' circadian rhythms and to decrease 
drivers' non-driving workload and extended detention periods.
    A short-haul carrier that hauls loads with special hauling permits 
said the 11-hour limit had been especially helpful, because in most 
states it could only move loads during daylight hours. The 11-hour 
limit allowed drivers to take advantage of the longer daylight in the 
summer months to drive additional miles, thus increasing efficiency. 
The carrier also said that the extra hour of driving enabled its 
drivers to get through metropolitan areas that had a curfew during rush 
hour periods. Some of its drivers were now able to deliver one 
additional load per week, which increased driver earnings while 
improving the company's efficiency.
Opposition to 11-hour Limit
    Opposition to the 11-hour daily driving limit came from 152 
commenters, including safety advocacy groups, unions, and a minority of 
drivers.
    Advocacy groups presented the most detailed arguments. IIHS stated 
that it did not believe the increase in daily driving time from 10 to 
11 hours was supported by scientific evidence. Public Citizen argued 
that FMCSA had not presented in the 2005 NPRM any evidence 
demonstrating that any changes the Agency would make to the HOS rules 
would make the eleventh driving hour safe, much less improve safety, in 
accordance with the Agency's statutory mandate. These commenters argued 
that FMCSA had failed to demonstrate how a driver's initial restfulness 
can ``offset'' the safety risk presented by the additional hour of 
consecutive driving.
    AHAS said that FMCSA had recognized and documented in its May 2000 
proposed rule that the risk of a crash by a commercial driver increases 
at a geometric or logarithmic rate as the consecutive hours of driving 
increase in each shift. AHAS concluded that by allowing an eleventh 
consecutive hour of driving, the Agency has increased the absolute risk 
of commercial drivers being involved in fatigued-related crashes.
    The International Brotherhood of Teamsters said that any benefits 
of the 10-hour rest period and the 14-hour duty-tour were offset by the 
one-hour increase in daily driving time and the 34-hour restart 
provision. The Transportation Trades Department of the AFL-CIO said 
that ``[r]equiring a ten percent increase in driving time as a solution 
to driver fatigue makes little sense.''
    Some commenters suggested that drivers were being pressured to 
drive the entire 11 hours. An attorney with the Truckers Justice 
Center, who said that he had represented drivers in proceedings under 
the Surface Transportation Assistance Act (STAA) in which the drivers 
were disciplined for refusing to drive while impaired due to fatigue, 
opposed the 11-hour daily driving limit. He said that the Truckers 
Justice Center had spoken with drivers who were concerned about the new 
hours of service provision allowing a carrier to force a driver to 
drive up to 11 hours in a single tour of duty.
    Several commenters presented detailed arguments in favor of a 10-
hour limit. The National Institute of Occupational Safety and Health 
(NIOSH) said that its comments submitted to FMCSA in December 2000 were 
still valid. Those comments supported a limit of 10 hours of driving 
within a 24-hour work/rest cycle of 12 hours on duty and 12 hours of 
free time. NIOSH said that this daily cycle would be consistent with 
common scheduling practices in other industries that use shifts longer 
than 8 hours.
    Both Public Citizen and AHAS suggested that drivers should be 
allowed to accrue no more than 10 consecutive hours of driving in a 
shift. Both added that the research literature and FMCSA itself have 
shown that allowing fewer than 10 consecutive hours would result in 
even safer operations. Several drivers also supported a 10-hour limit.
Economic Effects of 11-Hour Limit
    The Corporate Transportation Coalition (CTC) stated that its few 
member companies that engage in long-haul operations believe the 11th 
hour of driving has permitted modest productivity gains. Brandt Truck 
Line, Inc. stated that the additional hour had improved productivity 
(especially in a 50-mph State) by eliminating the need to incur a 
sleeper-berth period during the return trip. This allowed the use of 
day cab tractors (not sleepers), and a miles per gallon improvement of 
15 percent, and a ``gain'' of nearly 20 hours per week in scheduling 
continuity, which allows drivers to continue the same scheduled route 
each day, rather than changing routes on a day-to-day basis.
    ABF Freight stated that in 2004, only 4.6 percent of its dispatches 
required the 11-hour rule to complete runs. While this might rise 
slightly should the rule become permanent, it was not likely to affect 
the majority of its dispatches, due to the fixed nature of its service 
center markets. The Overnite Transportation Company stated that the 11-
hour driving rule made its operations cheaper and more efficient, 
because it could now haul freight directly, thus using fewer drivers 
and fewer tractors and trailers driving fewer miles. The company saves 
over $110,000 annually and is able to provide faster transit times.
    Georgia-Pacific Corporation stated that productivity is an 
appropriate factor for FMCSA to consider because the only other 
alternative is to increase the numbers of trucks on the highways, with 
accompanying congestion and crashes.
    J. B. Hunt said that it randomly selected 80 of its over-the-road 
drivers and tracked them for a 30-day period. The carrier found that 
the drivers used the 11th hour of driving only 10 percent of the time. 
National Ready Mixed Concrete Association (NRMCA), the Massachusetts 
Concrete and Aggregate Producers Association, and a carrier

[[Page 50009]]

stated that driving time is generally not a critical issue in the ready 
mixed concrete industry. NRMCA cited its 2000 Survey of Ready Mixed 
Concrete Truck Driver Activities and Company Operations (Appendix II), 
which it said showed that ``concrete delivery professionals'' on 
average spend less than half of their time actually driving under the 
U.S. DOT definition. Therefore, the 1-hour increase in driving time 
contained in the 2003 rule was ``largely inconsequential'' to the ready 
mixed concrete industry.
Health and Safety
    Commenters generally reported that the increased driving time 
either had no impact (57 commenters) or a negative impact (62 
commenters) on health or safety.
    Advocacy groups saw a clear negative impact. For example, IIHS 
cited numerous scientific studies that it said show an increase in 
crash risk among drivers operating large trucks for more than 8 to 10 
hours. No scientific evidence, IIHS concluded, supports the argument 
that the increase in the daily off-duty requirement meant that the 1-
hour increase in driving time would not compromise safety.
    Public Citizen argued that numerous studies demonstrate that 
increased fatigue and risk are associated with longer consecutive hours 
of driving. They claimed that FMCSA's proposed addition of an hour of 
driving time would add an hour of exceedingly heightened crash risk, 
because the latter hours of driving are the most dangerous. Further, 
they asserted that the proposal undermined the Agency's duty to enhance 
safety. It cited a 1996 study that found a strong relationship between 
single-vehicle truck crashes and the length of consecutive hours spent 
driving, with the risk of a crash found to double after 9 hours of 
continuous driving. Public Citizen reported another study of truck 
driving that found that ``Accident risk increases significantly after 
the fourth hour, by approximately 65 percent until the seventh hour, 
and approximately 80 percent and 150 percent in the eighth and ninth 
hours,'' respectively. They also cited FMCSA's statement in the 2000 
NPRM that ``performance begins to degrade after the eighth hour on duty 
and that this degradation increases geometrically during the 10th and 
11th hours.'' They pointed to a chart in the 2000 NPRM based on data 
from the University of Michigan Transportation Research Institute 
(UMTRI), Trucks Involved in Fatal Accidents (TIFA) database, which it 
said clearly showed a striking rise in the relative risk of a fatigue-
related crash once drivers pass the 9-hour mark. In fact, it asserted 
that risk doubles between the tenth and eleventh hours of consecutive 
driving. Public Citizen also stated that the 1-hour reduction in on-
duty hours, from 15 hours to 14 hours, is irrelevant in terms of the 
number of driving hours. Drivers will tend to gravitate toward the 
maximum driving hours possible to enhance their earnings and meet trip 
deadlines, they argued, and will minimize non-driving on-duty hours.
    In contrast, the California Highway Patrol stated that the 
increased risk from the 11th hour of driving would be offset by limits 
on the length of the driver's overall work day.
    Yellow Roadway Corporation stated that about six percent of 
Roadway's single man line-haul operations use the 11-hour clock. 
However, it was unable to break out OSHA data for those drivers. The 
company did compare OSHA Recordable Injury data of line-haul drivers in 
total for the years 2003 and 2004, and said these data show an 
improvement of 55 percent from 2003 to 2004. Roadway suggested that 
although there may not be a direct correlation to the 11-hour driving 
rule, the significant decrease in injury rate for the entire line-haul 
operation would suggest that there is no safety or health related need 
to change the 11-hour rule.
    Alertness Solutions, a scientific consulting firm, submitted a 
literature review and technical argument supporting the proposition 
that there are very limited data to address a drive-time restriction 
and, from a physiological perspective, less foundation to establish how 
drive time relates to fatigue. The minimal data available, the 
commenter said, do not show significant differences between 10- and 11-
hour drive times. However, Alertness Solutions agreed that a drive-time 
limitation could be useful in creating breaks within a duty period, and 
breaks have been demonstrated to be an effective strategy to maintain 
performance and alertness.
    American Moving and Storage Association (AMSA) stated that the 
additional hour of driving time has had no adverse effect upon fatigue-
related highway crash experience. The benefits of the existing hours-
of-service rules, however, extend beyond highway safety to driver 
acceptance. AMSA reported that one carrier's driver out-of-service rate 
declined from 14 percent in 2003 to ten percent in 2004, a 29 percent 
improvement. That carrier's number of HOS out-of-service violations 
similarly experienced a 29 percent improvement. Another carrier found 
the number of its drivers who received false log citations during 
roadside inspections decreased 23 percent from 2003 to 2004. AMSA 
attributed this to the implementation of the 2003 rule, which more 
naturally fit a driver's daily routine and natural circadian cycle. 
AMSA also suggested that the 2003 rule is easier for drivers to 
understand and easier for dispatchers to work with than the former 
hours-of-service regulations. Moreover, the ability to drive for an 
additional hour provides operators of household goods moving vans the 
flexibility they need to arrive at a destination. Even the relatively 
small 1-hour addition to allowable driving time is a tremendous 
advantage to the operational efficiency required of all motor vehicle 
operations, considering the improvement in comfort, noise penetration, 
and maneuverability of commercial motor vehicles today that makes them 
less fatiguing to operate than those of even ten years ago. AMSA 
concluded that given the one-hour reduction in a driver's overall 14-
hour duty day, the additional hour of driving time was desirable, and 
an equitable and balanced complement to a driver's schedule.
    OOIDA reported that a survey it had conducted indicated that the 
11th hour of available driving time was not always used frequently by 
drivers. For the month of June 2004, the average driver used the 11th 
hour 8.3 times. According to OOIDA, drivers reported that the 
occasional use of this extra driving time had given them the ability to 
arrive at a familiar facility where there is room to park their truck, 
or to get them home where they have the best opportunity for rest and 
restorative sleep. This 11th hour is also used to complete the delivery 
of a load, taking the pressure off the driver to deliver the next day. 
OOIDA reported that drivers said they do not believe that the extra 
hour of driving impaired their safe operation of a CMV, and that it 
often put them in a position to obtain better rest or sleep. They would 
like to retain this flexibility.
    FedEx Corporation reported that FedEx Freight has no drivers who 
were consistently logging 11 hours of driving. FedEx Freight has no 
regular runs that require a driving time of 11 hours. Only about 2 
percent of bid runs had a driving time of between 10 and 10.5 hours. No 
crashes had occurred after the 10th hour of driving.
    Several drivers suggested that the 11-hour driving period should be 
limited by other requirements, or they suggested other limits.
FMCSA Response
    Because of the importance of driving time to this rule and the 
conflicting

[[Page 50010]]

views of the commenters, FMCSA examined a wide range of research 
literature and statistical data and performed a careful cost/benefit 
analysis of two alternative driving limits: 10 hours and 11 hours. The 
agency has decided to adopt a driving-time limit of 11 hours within a 
14-hour window following 10 consecutive hours off duty.
Crash Data
    Although FMCSA's analysis of the available crash data is presented 
in detail in section H, some of the information bears repeating here.
Trucks Involved in Fatal Accidents (TIFA) Data
    The TIFA file combines data on fatal crashes from FARS with 
additional data collected by UMTRI, including the number of hours 
driven since the last 8-hour off-duty period at the time of the crash.
    Campbell [Campbell, K.L. (2005)] reviewed TIFA data for the years 
1991 through 2002 to identify the operating conditions where the most 
fatigue-related crashes occur and to determine the association of 
fatigue risk factors with fatal crashes. He found that the majority of 
fatigue-related crashes occur in the early hours of the trip. This is a 
function of exposure, since all drivers drive in the first hour, while 
fewer drive in later hours, i.e., the early hours of trips are the most 
frequently driven. However, when examining the relative risk of a 
fatigue-related crash by hours of driving, the results are different. 
The likelihood a truck driver was fatigued at the time of a fatal crash 
generally increases with the number of hours driven. TIFA data show 
that the relative risk of a large truck being involved in a fatigue-
related crash in the 11th hour of driving or later is substantially 
higher than in the 10th hour of driving.
    TIFA data are not necessarily applicable to this rulemaking, 
however. Only 9 fatigue-related fatal crashes where the driver was 
operating in the 11th hour were recorded between 1991 and 2002. The 
statistical significance of such a small number is questionable. TIFA 
data were collected when the minimum off-duty period was only 8 hours 
and the driving limit 10 hours. The current 10-hour off-duty 
requirement means drivers have so much more opportunity for restorative 
sleep that the relative risk of the 11th hour of driving revealed by 
TIFA may no longer be relevant. Finally, UMTRI conducts interviews with 
drivers or carriers to supplement the FARS data, but may do so as much 
as a year after a crash. It is unclear whether drivers can accurately 
recall the number of hours they had driven that long after the event.
Virginia Tech Transportation Institute Study
    The Virginia Tech Transportation Institute (VTTI) is currently 
conducting a real-world, empirical study of crash risk during the 10th 
and 11th hour of driving.
    The researchers have found no statistically significant difference 
in the number of ``critical'' incidents in the 10th and 11th hours of 
driving [Hanowski, R.J., et al. (2005), p. 9]. The study has also 
determined that drivers are not measurably drowsier in the 11th than 
the 10th hour of driving. These results may be related to another 
finding, that drivers appear to be getting more sleep under the 2003 
rules than they did when the minimum off-duty period was only 8 hours. 
Compared to four sleep studies conducted under the pre-2003 rules, 
Hanowski and his colleagues found that drivers operating under the 2003 
rule are averaging over 1 hour of additional sleep per day [Id., p. 8].
Crash Risk and Hours Driving: Interim Report II
    The Pennsylvania Transportation Institute at Pennsylvania State 
University is currently modeling the effect on crashes of hours of 
driving, hours of rest, multi-day driving patterns and other factors 
under the 2003 rule [Jovanis, P.P., et al. (2005)]. This study 
collected records of duty status (RODS) for 7-day periods prior to 
crashes, as well as for a non-crash control group. The study found an 
increased crash risk associated with hours of driving, particularly in 
the 9th, 10th and 11th hours, and multi-day driving.
Comments on Crash Risk and Data
    Many companies and associations submitted data on crash and injury 
rates. In general, their data show that crash and injury rates were 
lower in the year since the 2003 rule went into effect in January 2004.
    ATA reported data showing that carriers had statistically 
significant lower average crash rates in 2004, causing ATA to believe 
that the 2003 rule is superior to the pre-2003 rule from the 
perspective of overall safety.
    The information provided by commenters is not available from other 
sources, but there is certainly some variability in the methods and 
accuracy with which the data were collected. In addition, the lower 
crash and injury rates cannot be definitively attributed to the effects 
of the 2003 rule, though some commenters noted that the rule is the 
only major variable that changed from 2003 to 2004. Finally, the data 
do not reveal anything about the relative risk of the 10th or 11th hour 
of driving.
Fatality Analysis Reporting System (FARS)
    FARS is generally recognized as the most reliable national database 
on fatal motor vehicle crashes. FMCSA compared the first 9 months of 
FARS crash data from the 2003 Annual Report with the first 9 months 
from the 2004 Early Assessment File (the difference is explained in 
Section H).
    The total number of fatal crashes involving large trucks decreased 
from 3,120 in 2003 to 2,954 in 2004, a 5.3 percent reduction. The 
number of large truck crashes where the driver was coded as fatigued 
dropped as well. More important than either of these figures, however, 
are the data showing that fatigue-related fatal crashes are down from 
1.7 percent of all crashes in 2003 to 1.5 percent in 2004, an 11.8 
percent reduction.
    Although the data are still preliminary, all FARS measures of 
fatigue-related crashes are trending downward. The data, of course, do 
not allow any firm conclusion about the extent to which the 2003 rule 
may have contributed to that result.
Operational Data
    FMCSA gathered operational data during compliance reviews and 
safety audits to determine how the various provisions of the 2003 rule 
are being employed by the motor carrier industry. The Agency also 
reviewed other survey material and comments to the docket on this 
subject. Available data indicate that driving into the 11th hour is far 
from universal, with utilization rates ranging from 10 to 28 percent. 
FMCSA's own survey of driver records found that only 20.7 percent of 
the recorded driving periods exceeded 10 hours. There is no reason to 
believe that a full 11 hours of driving will ever become the standard 
for the industry. Drivers need to deal with operational, 
administrative, and personal matters which typically reduce driving 
time well below the maximum allowable hours.
    As stated above, numerous carriers support the 11th hour of driving 
since it allows drivers to return home within a day so they can sleep 
in their own beds. FMCSA also notes that the provision has increased 
industry productivity through increased flexibility without impacting 
safety based on available data, specifically crash rates (see Crash 
Data discussion, above). A number of commenters said that, since trip 
lengths have not changed

[[Page 50011]]

as a result of the 2003 rule, the 11th hour serves primarily to reduce 
the stress of trying to complete a run by the end of the 10th hour. 
With an extra hour of driving time, drivers are able to relax a bit and 
perhaps drive less aggressively.
    As noted in the comments, use of the 11th hour is also justified 
due to improvements in truck comfort, noise penetration, and 
maneuverability, which have decreased trucker fatigue over the past 
decade.
Research and Literature Review
    The scientific literature on fatigue and performance factors 
includes notably different, and indeed inconsistent, results. The 
Agency found that the research on driving time is limited and the 
conclusions mixed. A fatigued driver is prone to perform less 
effectively on tasks requiring vigilance and decision-making than a 
person who is alert. Fatigue is associated with a higher degree of 
crash risk. In practice, however, it is difficult to establish the 
precise effect a given driving or on-duty period will have on fatigue, 
alertness, or driver performance. Modest differences in study designs 
may produce surprisingly different results.
    Research on the effects of driving time falls into three 
categories: (1) Operational studies of on-road working environments, 
(2) laboratory studies under controlled conditions, sometimes using 
driving simulators, and (3) analysis of crash or performance data. The 
results are far from uniform.
    Operational and laboratory studies have generally found little or 
no statistically significant difference in driver drowsiness or 
performance between the 10th and 11th hours of driving [O'Neill, T.R., 
et al. (1999), p. 48; Wylie, C.D., et al. (1996), pp. 5.13-5.14; 
Hanowski, R.J., et al. (2005), p. 9]. These findings are contradicted 
by other research involving drivers operating under the pre-2003 HOS 
rule. A frequently-cited 1978 study found evidence of fatigue, measured 
both subjectively and objectively, in less than the 10 hours of driving 
then allowed by the HOS rules [Mackie, R.R., & Miller, J.C. (1978), pp. 
219-221]. This study, however, required a driver to take only 8 
consecutive hours off-duty, which probably limited the hours actually 
available for sleep (as discussed later in section J.7). The 2003 rule 
and today's final rule provide drivers an additional 2 hours off duty, 
creating a much improved opportunity for 7 to 8 hours of sleep per day.
    Research analyzing crash and performance data usually focuses on 
police reports and driver records of duty status (RODS) to establish 
crash-risk factors, like the time of day the crash occurred, the number 
of hours driven since the last off-duty period, the number of hours 
since the last sleep period, and the length of the last sleep period. 
As mentioned above, these studies typically find that the risk of a 
fatigue-related crash increases with the number of hours driven, and 
particularly after the 10th hour. On the other hand, sample sizes for 
the 11th hour of driving, and beyond, are very small, and data 
collection procedures for TIFA are less than optimal.
    The evaluation of some research, particularly in the operational 
category, is complicated by the variations in study design and data 
collection.
    A 1996 operational study of 80 long-haul drivers engaged in 
revenue-generating runs in the U.S. (under the 10-hour driving limit) 
and Canada (under that country's 13-hour driving limit) reported that 
time-on-task was not a strong or consistent predictor of observed 
fatigue. This study found no difference in drowsiness, as observed in 
video records of comparable daytime segments, between 10 and 13 hours 
of driving. Some measures, such as lane tracking, individual cognitive 
performance, and self-rating of fatigue were better at 10 hours of 
driving than at 13 (lane tracking was confounded by differences in 
driving routes and road conditions in the two countries). Conversely, 
reaction time was better at 13 hours of driving than at 10. The authors 
noted that the lack of variance in drowsiness between the driving 
periods may be attributable to the fact that the study measured only 
daytime drowsiness. Other research suggests the body's circadian rhythm 
limits the negative effects of longer hours during daytime operations 
[Wylie, C.D., et al. (1996), pp. 5.13-5.14].
    A 1999 study evaluated the effects on fatigue and performance 
during a daytime schedule of 14 hours on duty and 10 hours off duty, 
with drivers performing simulated driving and loading/unloading tasks. 
The authors found mild cumulative effects on subjective measurements of 
sleepiness; a slight but statistically significant deterioration in 
duty-day subjective sleepiness, reaction time response, and measures of 
driving performance over the course of a week; but no cumulative 
deterioration of driver response in crash-likely situations. The 
authors reported that a schedule of 14 hours on duty (with 12 hours of 
driving) and 10 hours off duty for 5 consecutive day periods did not 
appear to produce significant cumulative fatigue over the 2-week 
testing period [O'Neill, T.R., et al. (1999), p. 48].
Breaks, Naps and Driver Fatigue
    The Agency considered a mandatory rest period (break) to mitigate 
any possible fatigue related to the 11th hour of driving. Scientific 
research suggests that rest breaks, including naps, while not reducing 
accumulated fatigue, refresh drivers and enhance their level of 
performance and alertness on a short-term basis [Belenky, G. L., et al. 
(1987), p. 1-13 ; Wylie, D. (1998), p. 13]. The Agency concluded that 
such a break would be difficult for State and Federal enforcement 
personnel to verify and would significantly interfere with the 
operational flexibility motor carriers and drivers need to manage their 
schedules.
    Still, FMCSA encourages carriers to establish a break or napping 
policy as part of an overall fatigue management program. Several 
studies have shown that a nap during a night shift can lessen the 
fatigue felt overnight [Matsumoto, K., & Harada, M. (1994), p. 899; 
Rogers, A.S., et al. (1989), pp. 1202-1203]. A study found that a 20-
minute ``maintenance'' nap helped to improve daytime self-rated 
sleepiness and performance levels on a variety of tasks, including 
logical reasoning, mathematical calculations, and auditory vigilance 
[Hayashi, M., et al. (1999), p. 272]. Research suggests that a short 
nap of 10 to 20 minutes (but generally for less than 45 minutes) can 
provide a beneficial boost in driver alertness.
Driver Health Impact
    The issue of CMV driver health is complex, and involves many 
external factors (lifestyle, diet, and other personal behavior/choices) 
that are beyond the scope of the HOS rules. As discussed above (Section 
E--Driver Health), FMCSA found little research on a possible 
relationship between HOS regulations and driver health. Longer driving 
time increases driver exposure to diesel exhaust and chemicals, noise, 
and vibration, but dose/response curves clarifying the effect of such 
exposure do not exist. Therefore, in the Agency's best judgment, the 
difference between a driving limit of 10 and 11 hours is 
inconsequential from the standpoint of driver health.
Conclusion
    Available information on the effect of allowing 11 hours of driving 
time is inconclusive. TIFA classified only 9 fatal crashes that 
occurred in the 11th hour of driving as fatigue-related between 1991 
and 2002. Whatever the statistical risk of driving in the 11th

[[Page 50012]]

hour, FMCSA cannot make a reasonable choice between a 10- and an 11-
hour driving limit on the basis of only 9 fatal crashes over a 12-year 
period.
    The on-going studies by the Virginia Tech Transportation Institute 
and the Pennsylvania Transportation Institute seem to have reached 
completely incompatible conclusions. The latter finds that the 11th 
hour of driving poses a significant crash risk while the former detects 
no statistical difference between the 10th and 11th hours of driving. 
The different methods used by both research teams appear to be valid.
    Trucking industry comments to the docket generally reported lower 
crash and injury rates in 2004 than in 2003. This reveals nothing about 
the 11-hour driving limit or the 34-hour restart provision, nor can the 
improvements be clearly linked to the 2003 rule, but it certainly 
implies that the 2003 rule has not harmed highway safety.
    Preliminary FARS data show that fatigue-related fatal crashes as a 
percentage of all CMV fatal crashes were down in the first nine months 
of 2004 compared to the same period in 2003. This is consistent with 
the information provided in motor carrier comments to the NPRM. The 
data do not allow a calculation of crash risk for each additional hour 
of driving. It is also possible, however unlikely, that the FARS Early 
Assessment File for 2004 does not accurately reflect the data in the 
2004 Annual Report, which was not available when FMCSA conducted its 
analysis.
    In summary, the available crash data do not clearly indicate 
whether the 11th hour of driving, combined with 10 hours of off-duty 
time, poses a significant risk.
    An 11-hour driving limit is favored by most motor carriers and 
drivers, and is economically beneficial to some carriers. On the other 
hand, it provides no real advantage over a 10-hour limit for many 
short-haul carriers. Advocacy groups and some drivers prefer shorter 
driving times, though there is no consensus on what the shorter limit 
should be. Use of the 11th driving hour varies widely among motor 
carriers and individual drivers, but all available data show 
utilization rates far below 50 percent. The research literature on 
driver health is not sufficiently detailed to differentiate between any 
possible effects of a 10- and an 11-hour driving limit. Like the crash 
research and data, the comments and operational data do not point 
unambiguously toward a single conclusion.
    FMCSA carried out a cost/benefit analysis of a 10- and 11-hour 
driving limit and other aspects of this final rule, as reported in 
section K.1 and the stand-alone Regulatory Impact Analysis (RIA) filed 
in the docket. Motor carrier operations were modeled in detail. The 
Agency used a time-on-task multiplier which assumed that the crash risk 
from the 10th to the 11th hour of driving increased based on the TIFA 
data. The analysis demonstrated that a 10-hour driving limit would save 
no more than 9.3 lives per year compared to an 11-hour limit. The 
annual net cost of a 10-hour limit, however, compared to an 11-hour 
limit, would be $526 million ($586 million in gross costs minus $60 
million in safety benefits). A 10-hour driving limit would cost more 
than $63 million per life saved.
    While the Agency did not explicitly estimate the marginal costs and 
benefits of limiting daily driving to 8 or 9 hours, FMCSA believes that 
such changes would be even less cost beneficial than a 10-hour driving 
limit and would allow a driving/rest cycle less consistent with driver 
circadian rhythms than an 11-hour limit. See section H for further 
discussion of this issue.
    FMCSA is required by statute both to improve motor carrier and 
driver safety and to consider the costs and benefits of its 
requirements [49 U.S.C. 31136(c)(2)(A) and 31502(d)]. The Department of 
Transportation currently uses $3 million as the ``value of a 
statistical life'' (VSL) for rulemaking purposes. Because a 10-hour 
driving limit would cost $63 million per life saved, compared to an 11-
hour limit, the VSL for the lower limit would be 21 times the DOT 
standard. A $63 million VSL is over six times higher than the maximum 
VSL cited by the Office of Management and Budget (OMB) in its guidance 
to Federal agencies on conducting regulatory impact analyses, i.e., $10 
million [OMB Circular A-4, p. 30]. The Agency cannot impose regulatory 
costs so far in excess of regulatory benefits. FMCSA expected the new 
10-hour off-duty period required by the 2003 rule to reduce driver 
fatigue and improve safety, despite allowing 11 hours of driving time 
instead of 10 hours. Many, though not all, motor carriers have reported 
lower crash and injury rates under the 2003 rule, and preliminary FARS 
data show that fatigue-related fatal truck crashes have declined as a 
percentage of all fatal CMV accidents. This suggests that the pre-2003 
studies and data showing a sharply increased crash risk in the 11th 
hour of driving may no longer be relevant because drivers have used the 
10 off-duty hours required by the 2003 to reduce fatigue. It is thus 
FMCSA's judgment that the $526 million net cost of a 10-hour driving 
limit is too high to justify the potential benefits it would generate. 
Today's final rule therefore sets the maximum allowable driving time at 
11 hours after 10 consecutive hours off duty.

J.6. Duty Tour

    In the 2005 NPRM, FMCSA requested comments on the impacts of the 
2003 rule decrease in the duty period for drivers from 15 non-
consecutive hours to a non-extendable 14 consecutive hours.
Impacts on Safety and Health
    Almost 600 drivers and about 100 carriers, as well as OOIDA, the 
National Association of Small Trucking Companies, CTC, and NPTC, urged 
that breaks, meals, and time spent loading and unloading be exempted 
from the 14-hour duty tour. A substantial majority of commenters, 
mostly drivers and owner/operators, opposed the change from 15 
cumulative hours to 14 consecutive hours of on-duty time. Drivers, in 
particular, stated that the consecutive duty time requirement caused 
them to skip meals or naps when they were needed, and generally 
increased stress that leads to speeding and more aggressive driving. 
Several commenters believed the opportunity to work 14 consecutive 
hours compromised safety and favored a return to the previous 
requirement of 15 cumulative duty hours. Most of the commenters cited 
the need for meal breaks and other breaks for rest and exercise to be 
``off the clock,'' so drivers are not penalized for taking time to eat 
a meal or nap when they feel fatigued. Several trucking associations 
cited fatigue as the primary impact of the consecutive 14-hour rule. 
Because, they claim, drivers are discouraged from taking breaks to rest 
or have a meal, they drive straight through causing fatigue and stress. 
Two associations noted that the consecutive 14-hour rule has the 
unintended consequence of increasing the number of driver layovers, 
meaning that drivers more frequently sleep away from home, even though 
studies cited by FMCSA suggest that drivers who return home every day 
experience fewer fatigue-related, serious crashes than those who sleep 
while on the road. Many commenters urged FMCSA to revise the HOS rules 
to allow a driver to extend the 14-hour window by up to two hours by 
taking off-duty rest breaks throughout the day as needed. The Minnesota 
Trucking Association (MTA) reported that 51 percent of its drivers took 
naps to supplement sleep or maintain alertness. However, of the 49 
percent who did not nap, 42 percent

[[Page 50013]]

said that the 14-hour consecutive duty rule discouraged naps.
    The 131 commenters who approved the change to 14 consecutive duty 
hours made a variety of arguments in its favor. Several commenters 
believed the change was a positive one because it prevents shippers, 
receivers, and companies from abusing the off-duty hours and forcing 
drivers to use them as unpaid time. The National Industrial 
Transportation League (NITL) commented that 2003 rule ``supports driver 
productivity because the 14-hour window allows drivers ample time to 
perform such tasks as loading, unloading, fueling, vehicle inspection, 
and completion of paperwork that are part of a typical day.'' Advocates 
for Highway and Auto Safety stated that a return to a cumulative 
measure of duty time would restore the abusive practices that prevailed 
with the previous HOS rules, including the ability of shippers and 
receivers to intimidate drivers to wait in line for loads, load and 
unload their freight, and exceed maximum driving hours by concealing 
these actions as ``off the clock'' rest or meal breaks. Several 
commenters also noted that the consecutive hours requirement would 
promote safety by keeping drivers on a 24-hour circadian schedule.
Economic Impacts
    Several carriers noted that the 14-hour rule had increased their 
productivity and made their fleets more efficient. One carrier stated 
that the rule allowed it to pressure customers to speed up loading and 
unloading. In concert with a positive economic environment, this 
allowed a rate increase. Another carrier noted that the consecutive 14-
hour rule made it easier for a company to audit and manage driver 
hours, and that the rules were easier for drivers to understand and log 
their time accurately. The general consensus among drivers was that 
their workday, on average, is shorter under the new rules. They no 
longer work 20-hour days due to the 14-hour consecutive requirement. 
One driver stated that this is because shippers and receivers are more 
aware of the time restrictions that drivers face and do not delay 
drivers as long as they did in the past.
    The NITL commented that shippers have made significant changes. For 
example, ``operations at loading docks have been reconfigured to 
decrease dwell time and to expedite loading and unloading in order to 
minimize driver on-duty time not devoted to driving, and to maximize 
driving time with the new 14 consecutive hour rule.'' The changes were 
necessary given the ``new'' value associated with a driver's time. They 
too suggest that shipper and motor carrier operations have become more 
efficient in response to the 14-hour duty tour rule.
    Several other carriers, however, stated that the consecutive 14-
hour rule had caused a loss of productivity and fleet utilization, 
while increasing costs, thereby reducing profits. Some commenters noted 
that the inflexibility of the consecutive 14-hour rule 
disproportionately affects small businesses, many of which are forced 
to hire additional drivers to accommodate irregular delivery schedules. 
A few of these commenters also cited public safety concerns associated 
with the lack of flexibility. For example, the National Propane Gas 
Association stated that nearly 60 percent of its members are 
experiencing difficulty in handling emergency or after-hours calls 
requiring an immediate response. Short-haul drivers also stated that 
the 14-hour rule had increased costs and reduced productivity and 
driver earnings. The American Bakers Association surveyed its members 
and estimated the cumulative cost increase to its companies' 
distribution systems to be between 12 and 15 percent. Several 
commenters noted that the impacts to short-haul drivers are more 
significant than those imposed on long-haul drivers. Four commenters 
cited FMCSA's admission that, while the benefits of the new HOS rules 
accrue mostly to long-haul drivers, the cost burden falls largely on 
short-haul operators.
    Two carriers stated that the consecutive 14-hour rule imposes an 
economic penalty on long-haul drivers who wish to take a rest break and 
decreases their earning potential by not allowing the 14 hours to be 
extended.
FMCSA Response
    Under the pre-2003 HOS rule, a driver could extend the 15-hour on-
duty period by taking breaks during the day. Thus, the pre-2003 rule 
permitted an operator to drive after having been at work over 15 hours. 
The Agency ended this in the 2003 rule, by prohibiting drivers from 
extending their on-duty period with ``off-duty'' breaks. The 2003 rule 
prohibited driving after the 14th consecutive hour of beginning work or 
coming on-duty. This created a non-extendable period within which the 
driver could drive up to 11 hours and effectively ended the allowance 
of breaks to extend daily duty tours. The Agency's research found time 
spent working (and not simply time spent driving) contributes to a 
driver's fatigue and thereby impacts performance in long-haul 
operations [Williamson, A.M., et al. (1996), pp. 713-717; Williamson, 
A.M., et al. (2000), pp. 43-44; Van Dongen, H.P.A., et al. (2003), p. 
125].
    In developing this final rule, the Agency considered whether the 
scientific research, studies, data, and comments justified adopting a 
14-hour driving window, or required some other provision. As noted 
earlier, a number of commenters, drivers in particular, reported that 
the consecutive duty time requirement causes them to skip meals or naps 
when they are needed, and generally increases stress and leads to 
speeding and more aggressive driving. After a thorough evaluation of 
the data and comments, FMCSA has decided to allow drivers to drive up 
to 11 hours within a 14-hour window after coming on duty.
Crash Data
    The crash data reviewed by the Agency in developing this rule is 
discussed earlier in Section H. Several motor carriers and associations 
submitted data with their comments reflecting a decrease in crash and 
injury rates in 2004 compared with 2003. The data suggest a positive 
improvement in safety performance. It is impossible to definitively 
link a specific provision of the 2003 rule with the improved safety 
performance during 2004; however, the research and crash analysis show 
longer continuous work hours can increase the risk of a fatigue-related 
crash, as discussed later in this section. Further analysis suggests 
that the crash-impact of longer work hours is more specifically 
associated with large CMVs (greater than 26,000 pounds). Analysis of 
1994-2002 crash data found that these CMVs account for 87.3 percent of 
all fatigue-related fatal crashes [Campbell, K.L. (2005)].
Operational Data
    Based on the recent FMCSA survey [See Section I, FMCSA Field Survey 
Report (2005)] of 7,262 tour-of-duty periods, the Agency found that 
15.3 percent exceeded 12 hours and 9.2 percent exceeded 13 hours. 
Looking at over-the-road (OTR) driver tours of duty, 16.4 percent 
exceeded 12 hours and 9.4 percent exceeded 13 hours. These data show 
that the vast majority of drivers are not using the full 14-consecutive 
hour duty tour. The data suggest that drivers represented in the survey 
have time available within the current 14-hour duty tour to take 
breaks. The survey findings are based upon the review of 269 motor 
carriers, of which 85.9 percent (231) were for-hire motor carriers and 
14.1 percent (38) were private motor carriers. Of the for-hire motor 
carriers surveyed, the majority

[[Page 50014]]

(96.3 percent) were considered over-the-road. In contrast, of the 
private motor carriers surveyed, a slight majority (57.6 percent) were 
considered local. Additionally, the majority of motor carriers surveyed 
were classified as a truckload (92.6 percent) [FMCSA Field Survey 
Report (2005), p.4].
Research & Literature Review
    As described earlier in Section D, the Agency initiated an 
extensive review of scientific literature and research in developing 
this rule, which included the use of subject matter experts to assist 
in the effort.
    The Agency found general consensus within the research that 
cumulative wakeful hours have a direct correlation with a person's 
alertness and ability to maintain performance. Specifically, longer 
wakeful hours result in alertness and performance degradation. The 
research conclusions are conflicting, depending upon the type of 
research conducted, on the specific number of hours after which the 
degradation in alertness and performance adversely affect a driver's 
ability to safely operate a CMV.
    A 1999 simulator study found only a negligible difference in 
fatigue between a typical day (morning to evening) shift of 10- or 12-
hour duty day and a 14-hour day. This same study found that ``a daytime 
work schedule of 14-hours on-duty with a 10-hour off-duty period for a 
5-day week did not appear to produce cumulative fatigue'' [O'Neill, 
T.R., et al. (1999), pp. 37-41].
    A more recent study (2000) of New Zealand CMV drivers found ``0.05% 
BAC (Blood Alcohol Content) equivalence occurred at between 17 and 19 
hours of sleep deprivation for most tests. This means that after around 
17 hours of wakefulness, a person's performance capacity is 
sufficiently impaired to a level of concern for safety'' [Williamson, 
A.M., et al. (2000), pp. 43-44]. Another study of 48 healthy adults 
under standardized laboratory conditions found the critical wake period 
beyond which performance began to lapse was statistically estimated to 
be about 16 hours [Van Dongen, H.P.A., et al. (2003), p. 125]. These 
findings are generally consistent with comments by Alertness Solutions, 
which emphasized the importance of continuous wakefulness as a 
predictor of fatigue [Alertness Solutions, (2005) NPRM Docket 
comments].
    The role of continuous wakefulness is important in predicting 
fatigue, and thereby protecting driver safety and consequently public 
safety. Therefore, a duty period provision to control driver work hours 
is an important component of the HOS regulatory scheme. There is 
consensus among researchers that a schedule that promotes a 24-hour 
clock is beneficial in creating regularity of work/sleep schedules. 
Researchers also agree that individuals need 7-8 consecutive hours of 
sleep per day. The 14-hour duty tour along with a 10-hour off-duty 
period meets both of these universally accepted findings. This final 
rule promotes movement toward a 24-hour clock and provides all drivers 
with the opportunity to obtain 7-8 consecutive hours of sleep per day.
Driver Health Impact
    As discussed earlier, an FMCSA driver health team, despite 
extensive efforts, found little research to evaluate the specific 
impact or association between the specific hours driven or worked and 
CMV driver health. One can conclude, based upon the research, that 
sleep, along with hours worked, plays a role in a person's overall 
health.
    If long work hours adversely affect driver health `` which current 
research does not clearly indicate `` the 14-hour limit will protect 
drivers better than the pre-2003 rule. Drivers ordinarily are not 
allowed to extend their duty tour beyond 14 hours. The 14-hour 
provision is a substantial improvement over the pre-2003 rule, with its 
15-hour limit extendable by the amount of off-duty time taken during 
the duty tour, because this provision generally reduces daily work 
hours and any associated health effects. However, drivers operating 
under the new short-haul rule (described in section J.10) are allowed 
to drive up to the end of the 16th hour twice a week. There is no 
evidence that this short-haul schedule adversely affects drivers' 
ability to drive safely, and there is no available information on the 
health implications of an occasional 16-hour workday.

Conclusion

    After thorough consideration of the research studies, crash and 
operational survey data, and comments to the NPRM, the Agency has 
decided to prohibit driving after 14 consecutive hours after coming on 
duty. The Agency believes the information is clear on the need to limit 
the cumulative hours that a driver may work and continue to drive.
    It is the best judgment of the Agency that a 14-hour non-extendable 
duty tour period, in conjunction with 11 hours driving and 10 hours off 
duty, will reduce driver fatigue, promote driver health, and improve 
CMV transportation safety.

J.7. Off-Duty Time

    In the NPRM, the Agency requested comments on the extent to which 
the increase in the minimum off-duty time from 8 hours to 10 hours 
affected driver health, the safe operation of CMVs, and economic 
factors in the CMV industry. Of the 452 commenters who discussed the 
off-duty requirement, 270 (60 percent) approved of increasing off-duty 
time to 10 hours. For drivers who commented, the level of support was 
the same; 60 percent of the 366 expressed approval of the increase.
Impacts on Health and Safety
    A substantial majority (73 percent) of the comments on the health 
and safety impacts of the 10-hour break included positive consequences, 
particularly comments from drivers, but also from carriers.
    ATA, National Ready Mixed Concrete Association (NRMCA), National 
Industrial Transportation League (NITL), the Specialized Carriers and 
Rigging Association, the California Highway Patrol (CHP), the 
International Brotherhood of Teamsters, and three carriers said the 
increase in mandatory off-duty time gives drivers enough time to get 8 
hours of sleep as well as to attend to other personal needs. The AFL-
CIO, CHP and a carrier said that the 10-hour off-duty requirement, when 
combined with the consecutive 14-hour on-duty requirement, benefits 
drivers by putting them on a 24-hour daily schedule. Grammer 
Industries, Inc. said that the 10-hour off-duty requirement provides 
its drivers with the ability to exercise, take care of personal hygiene 
matters, eat meals, and spend time for relaxation. The carrier said 
that any break over 10 hours makes drivers out on the road ``nervous'' 
and causes them stress.
    Commenters also pointed out detrimental impacts. Werner Enterprises 
and two drivers said that the 10-hour period posed problems for over-
the-road drivers. Werner explained that because the break must be a 
full 10 hours, which is often more than a driver needs for sleep and 
daily personal maintenance, many drivers are frustrated when they wake 
because they must wait an additional 3 to 4 hours before they can go 
back on duty. The 10 hours off has little impact on long-haul drivers' 
personal or family activities because they are generally away from home 
then.
    J.B. Hunt also argued that the change had a negative impact on 
long-haul drivers. It reported surveying 697 drivers. The survey found 
that 32 percent indicated that going from 8 to

[[Page 50015]]

10 hours off was the ``least liked'' part of the new 2003 rule. The 
reason given by many was that they must now begin looking for parking 
locations by late afternoon or be forced to use ramp areas or other 
less safe break locations. Because there is no flexibility in requiring 
10 consecutive hours of break time, with the limited exception for 
split-sleeper periods that do not allow drivers to take care of their 
basic needs, drivers must often try to sleep in less-than-optimal 
sleeping conditions. Eleven drivers said that 10 hours off-duty is 
overly restrictive for those drivers who do not need 8 to 10 hours of 
sleep per night. Over-the-road and team drivers, in particular, found 
10 hours too long. Boston Sand and Gravel stated that the rule does not 
necessarily lead to increased sleep time, based on personal choices of 
the drivers in their use of off-duty time. Massachusetts Concrete and 
Aggregate Producers Association, Inc. also argued that 8 hours of rest 
was sufficient. ABF stated that most of its drivers would have 
preferred retention of the 8-hour rest period when away from home but 
liked the 10-hour period at home.
    Other commenters recommended a more substantial increase in the 
required break. NIOSH reiterated its support for a 24-hour work-rest 
cycle of 12 hours on-duty and 12 hours of free time. They also observed 
that the 12-on/12-off daily cycle is consistent with common scheduling 
practices in other industries that use shifts longer than 8 hours. IIHS 
said that the increase in required daily off-duty time is an important 
improvement, but it asserted that a 10-hour off-duty requirement still 
is inadequate for drivers to obtain restorative sleep and attend to 
other daily requirements. AHAS said that solo drivers should have at 
least 10 consecutive hours off-duty that are taken in a single block of 
time, regardless of whether that off-duty rest time is taken in a 
sleeper berth.
    McCormick proposed that any rest period equal to or greater than 10 
consecutive hours, within a 24 hour period, be considered the driver's 
sleep time. Under this approach, rest would be defined as sleep time, 
unloading delay time, or delays due to equipment breakdown.
    Kimberly Clark agreed that valid science supported a 24-hour work-
rest cycle. However, it recommended reducing the mandatory break from 
10 to 9 hours and allowing for a short nap during the duty day.
Economic Impacts
    Those carriers that commented generally said that the 10-hour break 
has a negative economic impact on them. One carrier stated that its 
trucks idle during each rest period, and longer periods reduce motor 
life and increase fuel costs. In addition, the trucks are less 
productive. Brandt Truck Lines reported an increase in drivers and 
vehicles of 15 to 25 percent, depending on schedules and how ``tight'' 
the operation was under the old regulations. Similarly, Colorado Ready 
Mixed Concrete Association stated that for overnight projects and 
during peak seasons, companies have had to hire additional drivers to 
comply with this provision of the regulation. However, ABF Freight and 
another carrier reported minimal impact.
    Relatively few drivers commented on the overall economic impact of 
the 10-hour off-duty period. One driver stated that the incremental 
increase in the minimum required off-duty period resulted in drivers 
making less money, as they are usually paid by the mile or trip, and 
more off-duty time means fewer miles or trips. Another driver said the 
rule increased frustration because it diminishes a driver's income.
FMCSA Response
    After thoroughly evaluating all of the information gathered, FMCSA 
has decided to require drivers to take a minimum of 10 consecutive 
hours off duty.
Crash Data
    The Agency has reviewed studies related to crash risk based upon 
the hours off duty and opportunity for sleep. Studies of truck drivers, 
[Lin, T.D., et al. (1993), p. 9; McCartt, A.T., et al. (1997), p. 63] 
point specifically to increased crash risk and recollections of 
increased drowsiness or sleepiness after less than 9 hours off duty. A 
study by the National Transportation Safety Board [NTSB (1996), p. 37] 
found the most critical factors in predicting fatigue were the duration 
of the most recent sleep period prior to the crash, length of time 
since last sleep period, sleep over the preceding 24 hours, and split-
sleep patterns. Drivers in fatigue-related crashes averaged 5.5 hours 
of sleep in the most recent sleep period prior to the crash (6.9 hours 
in the last 24 hours), while drivers in non-fatigue-related crashes 
averaged 8.0 hours of sleep (9.3 hours in the last 24 hours).
Operational Data
    As discussed earlier in Section I, industry surveys found that the 
2003 rule, with a minimum of 10 consecutive hours off duty, has 
generally improved driver rest (less fatigued) and encouraged movement 
toward a 24-hour work/rest cycle. The Minnesota Trucking Association 
(MTA) commented that a survey of their members found the 10 hours off 
has reduced fatigue, by providing more sleep and promoted better 
health. A study directed by FMCSA with VTTI (See Section H), which 
began monitoring 82 CMV drivers in May 2004, has found that drivers on 
average are getting more than an hour more sleep daily under the 2003 
rule. This finding is based upon comparisons of the VTTI data collected 
through May 1, 2005, to findings reported in research studies conducted 
under the pre-2003 rule.
    In addition to the operational data and surveys received from 
commenters, drivers submitted comments reporting that under the 2003 
rule they have more time at home and obtain more rest, resulting in 
reduced fatigue. The Agency believes that the increased sleep reported 
through industry surveys, operational data, and commenters can be 
attributed to the additional 2-hours off-duty time provided by the 2003 
rule.
Research & Literature Review
    As mentioned, FMCSA has found general consensus among scientific 
researchers regarding the human physiological need for 7-8 hours of 
sleep to maintain performance and alertness.
    Studies performed in laboratory settings, as well as studies 
assessing operational situations, have explored the relationship 
between sleep obtained and subsequent performance [Dinges, D.F., & 
Kribbs, N.B. (1991), pp. 98-121; Bonnet, M.H., & Arand, D.L. (1995), 
pp. 908-11; Belenky, G., et al. (1994), pp. 127-135; Dinges, D.F., et 
al. (1997), pp. 274-276; Belenky, G.L., et al. (1987), pp. 1-15 to 1-
17]. These studies generally found poorer performance levels when sleep 
is restricted. More recent studies [Balkin, T., et al. (2000), p. ES-8; 
Belenky, G., et al. (2003), pp. 9-11; and Van Dongen, H.P.A., et al. 
(2003), p. 124] found that even a relatively small reduction in average 
nighttime sleep duration (i.e., approximately 6 hours of sleep) 
resulted in measurably decremented performance. Another report 
[Rosekind, M.R., et al. (1997), pp. 7.2-7.5] concluded that 
``scientific data are clear regarding the human physiological 
requirement for 8 hours of sleep to maintain performance and 
alertness.'' ``Therefore, an average individual who obtains 6 hours of 
sleep could demonstrate significantly degraded waking performance and 
alertness * * *'' In addition, the authors found the effects of sleep 
loss/deprivation to accrue, and stated,

[[Page 50016]]

``* * * data have demonstrated that not only does the sleep loss 
accumulate but that the negative effects on waking performance and 
alertness also are cumulative and increase over time.''
    A past study of 80 over-the-road drivers in the U.S. and Canada, 
[Wylie, C.D., et al. (1996), p. ES-10] found that drivers obtained 
nearly 2 hours less sleep per principal sleep period than their stated 
``ideal'' (5.2 hours versus 7.2 hours).
    In a survey [Abrams, C., et al. (1997), pp. 11-12] of 511 medium- 
and long-distance truck drivers in the United States, the authors found 
no statistically significant differences in the stated rest needs among 
various categories of drivers (owner-operator, company driver, regular 
route, irregular route, solo, or team). On an average day, a driver 
reported needing an average of 7 hours of sleep.
    In 1998, an expert panel [Belenky, G., et al. (1998), p. 7] 
convened to advise the Agency on potential hours-of-service regulations 
for CMV drivers. The panel reported that ``off-duty hours must include 
enough continuous time off duty so that drivers are able to meet the 
demands of life beyond their jobs and are also able to obtain 
sufficient uninterrupted rest.'' In addition, the panel recognized that 
``although there is no guarantee that off-duty time will be spent in 
sleep, sufficient sleep cannot occur unless there is enough time 
allowed for it.'' The panel concluded that, ``the time allotted for 
sleep [off-duty time] must be a minimum of 9 [hours].'' The 
observations and recommendations made regarding continuous daily time 
off duty for CMV drivers supports the Agency's decision in this final 
rule to adopt the 10-hour provision.
    FMCSA is convinced, based upon the research, that drivers need the 
opportunity for 7 to 8 hours of consecutive sleep to maintain alertness 
and performance, and reduce fatigue on a daily basis. The Agency 
recognizes there are individual differences in the amount of sleep 
needed. However, the research overwhelmingly supports that on average 
humans require between 7 and 8 consecutive hours of sleep per day to 
restore performance. The Agency must ensure that this rule sufficiently 
provides for the average sleep needs of all CMV drivers. Establishing a 
rule requiring less than the average would result in sleep restriction 
over time that would lead to increased fatigue and reduced performance, 
thus elevating crash risk and compromising safety.
Driver Health Impact
    As discussed earlier, FMCSA found, despite its extensive literature 
review, little conclusive research to evaluate the specific impact or 
association between the specific hours driven or worked and CMV driver 
health. Anecdotally, one can conclude, based upon the research, that 
sleep plays a role in a person's overall health. Sleep deprivation has 
been associated with poorer health and increased health related 
problems, most notably cardiovascular disease, diabetes, and general 
health risks associated with obesity. The research supports 6-8 hours 
of sleep on average, as having a positive impact upon a person's 
health. Therefore, from a driver health standpoint, it is important 
that drivers be afforded the opportunity to obtain this amount of 
sleep. Based on the research that led to the 2003 rule, FMCSA knew that 
short sleep (sleep less than 6 hours) among drivers was a concern from 
both a safety and health perspective. As a result, FMCSA increased off-
duty time from 8 to 10 consecutive hours, thereby increasing the 
driver's opportunity for sleep by up to an additional two hours per 
day. Data, highlighted earlier, from multiple sources confirm that CMV 
drivers are obtaining more sleep as a result of the 2003 HOS rule, 
averaging more than an extra hour daily.

Conclusion

    After thorough consideration of the research studies, crash 
analysis reports, operational survey data, and comments to the NPRM, it 
is the Agency's best judgment that a requirement for a minimum of 10 
consecutive hours off duty is essential to give drivers the time needed 
to obtain restorative sleep every day. The Agency believes scientific 
research is clear on the need for 7 to 8 hours of sleep to maintain 
alertness and performance. Lack of sufficient sleep results in greater 
risk of involvement in a fatigue-related crash, and is associated with 
health-related complications. To ensure that drivers are afforded the 
opportunity to obtain 7 to 8 hours of sleep, the rule must afford a 
period of time greater than the minimum required for sleep. Drivers 
report being more rested, now that they have been afforded the 
opportunity to obtain 7 to 8 hours of sleep due to the increased off-
duty time. Adopting this provision acknowledges the importance of 
ensuring that the duration of the most recent sleep period before each 
duty tour is adequate to eliminate fatigue on a daily basis. The 
Agency's decision to adopt a 10-hour off-duty provision results in no 
new cost implications, compared to the 2003 rule.
    In addition, the Agency believes that a 10-hour off-duty period 
coupled with the 14-hour duty tour will promote movement within the 
industry toward a 24-hour clock. A 14-hour non-extendable duty tour, in 
combination with the longer off-duty period, enhances the opportunity 
for drivers to achieve restorative daily sleep compared to the pre-2003 
rule by eliminating the opportunity for the duty period to be extended. 
Ensuring that drivers have the opportunity for sufficient sleep, 
coupled with moving toward a 24-hour schedule, will reduce driver 
fatigue, promote driver health and improve CMV transportation safety.

J.8. The 34-Hour Restart and 60/70-Hour Rules

Introduction
    The following summarizes discussions contained in this and earlier 
sections of this preamble that are pertinent to the 34-hour restart and 
the 60/70 hour rules.
    This rulemaking addresses the phenomenon of driver fatigue, i.e., 
the partial and occasional total loss of alertness resulting from 
insufficient quantity or quality of sleep. Sleep plays a critical role 
in restoring mental and physical function, as well as in maintaining 
general health. For most healthy adults an average of 7 to 8 hours of 
sleep per 24-hour period has been shown to be sufficient to avoid 
detrimental effects on performance.
    It has been well established that mental alertness and physical 
energy rise and fall at specific times during the circadian cycle, 
reaching lowest levels between midnight and 6 a.m., with a lesser but 
still pronounced dip in energy and alertness between noon and 6 p.m. 
Changes of two or more hours in sleep/wake times cause one to become 
out of phase with the circadian cycle.
    Circadian de-synchronization results from irregular or rotating 
shifts that are not anchored to a 24-hour day (i.e., that start and end 
at different times each day), resulting in poor quality sleep and 
leading to accumulated fatigue. Sleep loss over several days leads to a 
degradation in alertness and driving performance. Sleep loss over 
extended periods or during night work can result in cumulative fatigue. 
Recovery from cumulative fatigue requires an extended off-duty period. 
CMV drivers who repeatedly obtain less than their daily requirement of 
sleep incur a sleep debt of some magnitude. In serious cases, the 
resulting cumulative fatigue can increase the driver's crash risk.

[[Page 50017]]

Recovery time is needed to erase the effects of sleep loss on 
performance, and in aggravated cases, to restore the mind and body to 
normal functioning.
    FMCSA has determined that the research on CMV drivers supports the 
assessment that a recovery period of 34 hours is sufficient for 
recovery from cumulative fatigue. The importance of two night (midnight 
to 6 a.m.) rest periods was highlighted in the 1998 HOS expert panel 
report. The majority of drivers (about 80 percent) are daytime drivers, 
who would likely start their recovery period between 6 p.m. and 
midnight, and therefore these drivers would have the opportunity for 
two full nights of sleep prior to the start of the next work week. 
Also, in examining the operational data, FMCSA has determined that many 
drivers are extending their recovery periods beyond 34 hours, making it 
even more likely that they are getting 2 full nights of sleep. More 
than 50 percent of drivers are getting 3 nights of sleep. FMCSA has 
concluded from its review of the few scientific studies of recovery 
periods that 34 hours off duty provides enough time for drivers to 
recover from cumulative fatigue that might occur during multi-day 
operations.
    In adopting the 34-hour recovery period, FMCSA has taken into 
account the weekly accumulation of driving and on-duty time allowed 
during each 7- and 8-day period, the adequacy of the 34-hour recovery, 
the costs versus benefits of retaining restart, the overwhelming 
support of the 34-hour recovery by the transportation industry, 
including motor carriers and drivers, the long-term effect on driver 
health, and the overall safety aspects of adopting this provision.
Support for Restart
    Of the 564 drivers who commented on the 34-hour restart provision, 
465 or 82 percent support it. Drivers cited a number of reasons why 
they like the 34-hour restart. It is long enough for them to get 
adequate rest before returning to work, but it is short enough that it 
does not significantly lessen their earnings. The provision gives 
drivers more time at home, gives them back the full allowable 70 hours 
for the coming 8-day week, and allows drivers to change shifts easily.
    Nearly all of the 113 carriers (including owner-operators) that 
discussed the 34-hour restart favor it. FedEx Corporation (FedEx) noted 
that the ``vast majority'' of FedEx Ground's contractors and their 
drivers use the restart provision, and anecdotal evidence from those 
contractors supports the 34-hour restart as a way to allow for 
sufficient rest and to address any potential HOS compliance issues. 
J.B. Hunt Transport said that it had conducted a survey of 697 drivers 
and that 67 percent of them thought the 34-hour restart provision was 
the ``most liked'' aspect of the new HOS rule. Schneider National, Inc. 
said that it had interviewed 46 experienced drivers and they all voiced 
support for the 34-hour restart provision, because the restart, in 
combination with the 10-hour off-duty requirement, prevents the build-
up of cumulative fatigue.
    Crete Carrier Corporation reported that since January 2004, its 
drivers more frequently request and receive longer periods of time off 
between consecutive days of driving in order to utilize the 34-hour 
restart. The carrier said that it now sees drivers proactively 
scheduling extended off-duty recovery periods into their workweeks and 
returning after these extended periods with ``positive attitudes and 
appearing rejuvenated.'' A regional carrier said that the restart 
provision benefits drivers by giving them a full day away from work to 
rest and relax. One carrier said its drivers haul over-dimensional 
loads that they cannot move on Saturday afternoons and Sundays in a 
number of states. With the 34-hour restart, however, these drivers get 
their 70 hours back after waiting out the weekend. Another carrier 
urged FMCSA to keep the restart provision because it directly affects 
its ability to retain and recruit drivers.
    Eighteen trade associations (trucking and other industries) also 
commented in favor of the provision. They cited benefits for both 
drivers and carriers. The associations said that the restart provision 
provides carriers with additional flexibility and allows increased 
productivity. In addition, they said that drivers are able to get home 
earlier and more often than they could under the pre-2003 rule.
Opposition to Restart
    A total of 109 commenters disapproved of the 34-hour restart 
period. Those drivers that opposed the 34-hour recovery period cited a 
number of reasons. For example, one thought it is too short to provide 
sufficient restorative sleep for short-haul drivers, and another 
thought it too long. Other drivers suggested that some carriers are 
forcing drivers to sit at truck stops for 34 hours rather than letting 
them spend their off-duty time at home. For example, one driver 
explained that ``A dispatcher can run a driver out of time (60/70 
hours). Then set him/her at a truck stop for 34 hours, 100 miles from 
home, then put him/her back on the road for another 60/70 hours. At 
least the old way, a driver could get home for a day or two. This way, 
the dispatcher can keep a driver out for a long time.''
    Public Citizen called the 34-hour restart provision one of the most 
harmful aspects of the proposed rule and strongly urged that it be 
eliminated. The group said that drivers should not be able to restart 
their driving hours by taking only 34 hours off duty. Public Citizen 
thought that drivers should be afforded a weekly off-duty period that 
includes at least two to three nights of rest after a week of driving.
    AHAS also opposed allowing drivers to restart their driving hours 
by taking only 34 hours off duty. It stated that drivers should be 
guaranteed the opportunity of at least three separate periods of sleep 
that are each equivalent to about 8 hours of sleep per night. It 
recommended that drivers have approximately 56 to 60 hours off duty 
before starting a new tour of duty, so that they can return to a 
regular pattern of waking and sleeping. AHAS referenced previous 
instances in which FMCSA acknowledged the importance of sleep periods 
taken at night. AHAS asserted that no research has shown that drivers 
can eliminate their fatigue, recover alertness and performance, and 
appropriately expunge an accumulated sleep debt with a 34-hour rest 
period. Furthermore, the group said that FMCSA had adopted the 34-hour 
restart provision ``in the face of a wealth of contrary evidence * * 
*.''
    The Insurance Institute for Highway Safety (IIHS) maintained that 
there is no scientific basis for the 34-hour restart rule. The group 
questioned the applicability of the 1999 study by O'Neill et al., which 
FMCSA cited as support for the 34-hour restart provision. IIHS noted 
that the study considered the effects of a 58-hour off-duty period, not 
a 34-hour period, and said that the study's authors cautioned about 
generalizing the results to operations with different characteristics. 
IIHS also noted that other studies have not reached the same 
conclusions. According to IIHS, a 1997 observational study of over-the-
road drivers found that a 36-hour recovery period was inadequate, and a 
2005 analysis of data from a national LTL firm suggested that there may 
be increases in crash risk associated with off-duty periods as long as 
48 hours.
    The Transportation Trades Department of the AFL-CIO also asserted 
that the 34-hour restart contributes to the physical exhaustion of 
drivers, because they receive only 34 hours off duty before beginning 
another ``marathon'' 7- or 8-day work assignment. The union said that 
the

[[Page 50018]]

restart provision dramatically cuts into the time drivers who operate 
on a weekly schedule would otherwise have to recover, catch up on 
sleep, and spend with their families. The International Brotherhood of 
Teamsters claims that any benefits of the 10-hour rest period and the 
14-hour tour of duty provision are offset by the increase in driving 
time and the use of the 34-hour restart provision. The union asserted 
that the 34-hour restart has become mandatory for most drivers who are 
not protected by collective bargaining agreements. The union said that 
their collective bargaining agreements do not provide for the use of 
the 34-hour restart. Despite this fact, the union does not think that 
the companies for which its members work have been competitively 
disadvantaged.
    Elisa Braver, University of Maryland School of Medicine, asserted 
that there is an absence of scientific evidence that the cumulative 
sleep deficits and fatigue incurred by working 60 hours can be remedied 
by having 34 hours off duty. She said that the scientific evidence 
cited by the Agency in support of the 34-hour restart is marred by 
small numbers, inapplicability to the driving population, and failure 
to study the effects of having 34 hours off after working according to 
the schedule permitted by the rule. As an example, Braver said that the 
study cited by O'Neill [O'Neill, T.R., et al. (1999)] featured small 
numbers of volunteers in driving simulators following a schedule unlike 
that of typical drivers who had 58 hours off between five-day work 
shifts. Braver cited a 2005 study which purportedly showed that 34 
hours is an insufficient period for recovery [Park, S-W., et al. 
(2005)]. Braver cited another study [Belenky, G., et al., (2003)] that 
she said indicated recovery from sleep deprivation can take longer than 
48 hours.
Adequacy of 34-Hour Recovery To Eliminate Fatigue
    By a large margin, the commenters who directly discussed the effect 
of the restart on fatigue said that it is long enough to provide 
sufficient restorative sleep, regardless of the number of hours worked 
prior to the restart. Of the 132 commenters who addressed the topic, 
113 said that 34 hours is long enough to provide sufficient restorative 
sleep.
    The Owner Operator Independent Drivers Association (OOIDA) noted 
that none of its members had reported needing more than two consecutive 
nights to obtain restorative sleep. The association said that drivers 
who use their 10 hours off duty to get sufficient restorative sleep 
never accrue a sleep deficit, so they are more than prepared to operate 
safely after the 34-hour restart. ATA said that the restart provision 
has improved the sleep/rest recovery period for drivers and enhanced 
their quality of life. It believes that the provision encourages 
carriers to more regularly schedule extended off-duty periods for 
drivers and that drivers are seeking to take that time off as a result 
of the restart provision. ATA also noted that the provision has helped 
to avoid the shifting of daytime to nighttime schedules, which research 
indicates can affect circadian rhythm and decrease alertness. CR 
England, Inc. said that the 34-hour restart offers irregular-route, 
long-haul drivers great relief from fatigue and sleepiness. The carrier 
noted that the restart is particularly beneficial to its drivers who 
want the rest but prefer to not spend their off-duty days away from 
home. The carrier called the restart provision a ``win-win situation 
for the driver'' because it allows higher earnings, enhanced safety, 
and improved family morale.
    Alertness Solutions provided a lengthy commentary on the rule. It 
stated that the 34-hour period provides sufficient time for two 8-hour 
sleep periods and one 18-hour period of intervening wakefulness that 
should allow recovery from a cumulative sleep debt. The daily 10-hour 
off-duty period is intended to minimize or eliminate any acute sleep 
loss, so any cumulative sleep debt that might exist under the HOS rule 
should be minimal or none. Any sleep debt that might occur under the 
rule should be sufficiently ``zeroed'' in the context of the 34-hour 
restart period. Alertness Solutions also argued that there are no 
scientific data that specifically address the number of work hours per 
week (or per month or per year) that would be required to cause fatigue 
serious enough to reduce performance, alertness, or safety. However, 
limiting the number of work hours in a specified timeframe is a common 
approach used in scheduling practices and in regulatory policies to 
address fatigue. Often these weekly limitations are calculated based on 
the daily limitations. For example, Alertness Solutions pointed out 
that a 14-hour duty limit, worked for 5 days yields a total of 70 hours 
of work. If considered in terms of historical practice related to a 
five-day workweek and two days off for a ``weekend,'' 70 hours of 
cumulative work hours in a 7-day period is consistent. As reflected in 
the FMCSA rule, these total work-hour limitations are even more 
conservative than this calculation. Also, because the daily limitations 
on duty and the provided off-duty rest are intended to minimize or 
eliminate acute fatigue, they represent a rational basis for 
calculating the cumulative work hours total. A core premise in the 
weekly work-hour limitations is that they both restrict the total work 
hours and provide a recovery period within a certain timeframe. The 34-
hour restart specifically addresses the recovery opportunity. Although 
there is no scientific basis for the weekly work-hour limitations, 
there are scientific data to address the recovery issue. Alertness 
Solutions also said there are some studies that have consistently 
demonstrated that two nights of sleep result in performance and 
alertness recovery following significant sleep deprivation.
    AHAS, however, said that FMCSA did not (and could not) demonstrate 
that drivers utilizing the 34-hour restart provision are no more 
fatigued and are just as safe as drivers were when operating under the 
prior regulatory regime. AHAS claimed that FMCSA ``simply relied upon 
its rulemaking authority to pronounce new, more demanding HOS 
requirements and to assert, without specific support anywhere in the 
record, that this expansion in driving hours and reduced time off would 
nevertheless somehow generate a net gain in safety.''
    IIHS agreed that FMCSA ignored studies showing an association 
between long driving hours and reports of falling asleep at the wheel 
of a large truck. IIHS added that among drivers it had interviewed, 
those reporting work hours longer than 60-70 per week, or other hours-
of-service violations, were 1.8 times as likely to report falling 
asleep while driving during the month prior to their interviews as 
drivers who reported they worked fewer hours.
    IIHS also critiqued Alertness Solution's comments. IIHS believes 
that the studies it referenced were not based on commercial vehicle 
drivers, but were primarily experiments that examine the effects on 
simulated performance of continuous hours of wakefulness, not time on 
task. IIHS said that the Alertness Solution commentary did not consider 
the range of factors that may affect sleep debts among truck drivers 
(e.g., split rest time in a sleeper berth) and their ability to get 
adequate recovery sleep in the real world. For example, IIHS noted that 
for many drivers the 34-hour recovery period occurs on the road rather 
than at home.
    Public Citizen thought that none of the research cited by FMCSA 
justifies a restart that provides for only two sleep periods, 
regardless of the time of day.

[[Page 50019]]

The group asserted that the minimum weekly recovery period that is 
supported by studies cited in the NPRM and earlier rulemaking notices 
is two consecutive nights of sleep. According to Public Citizen, the 
1999 simulator study concluded that two full nights and one intervening 
day--about 32 hours off duty--would be a minimum restart period, 
although the study actually studied 58-hour recovery periods and never 
looked at recovery periods brief as 32 hours. The group also said that 
another study cited by the Agency, performed in 1997, found that when 
participants using simulators received 36-hour and 48-hour recovery 
periods after four workdays, ``there was no objective evidence of 
driver recovery.'' Public Citizen also said that a 1997 literature 
review, which attempted to assess scientific support for a 36-hour 
restart, found no such support, and in fact found only one study even 
dealing with an operational schedule that allowed such a brief weekly 
recovery. Public Citizen quoted the authors that this was because 
``such a short reset period would result in schedules that would exceed 
current hours-of-work regulations in most countries.''
    Regarding the current 24 consecutive hour restart for utility 
service drivers, groundwater well transporters, and construction 
material truck drivers, which is not affected by this rule, Public 
Citizen noted that in 2000 FMCSA conceded that it ``ha[d] found no 
sleep or fatigue research that supports any of the current exceptions 
or exemptions, including the 24-hour restart provisions.'' The group 
said that at that time FMCSA recommended that these drivers be provided 
a weekly recovery that included at least two consecutive nights of 
sleep.
    The California Highway Patrol said that the 34-hour restart rule 
should be increased for all CMV drivers from 34 consecutive hours to 58 
consecutive hours. This would allow a driver time to commute, a minimum 
of three uninterrupted 8-hour rest periods, and 2 full days off duty 
before returning to work with zero hours on their 60/70-hour rule. 
Several drivers suggested that the restart period should be shorter 
(e.g., 24 hours) when drivers are on the road. One driver said, 
``Spending 34 hours (less sleeping time) doing nothing in a truck stop 
is more fatiguing than working.'' Another driver suggested that the 
restart period should be only 24 hours for team drivers.
Length of the Recovery
    Nearly half of the 87 commenters who discussed the appropriate 
length of the restart period suggested that it should be 24 hours; 48 
hours was the next most popular choice. Sixteen commenters voiced 
approval for 34 or 36 hours.
Use of Restart
    FMCSA requested information on how frequently the restart provision 
is being used. Ninety-five commenters responded, of whom 68 said that 
restart is being used weekly. Sixteen commenters said that the restart 
provision is being used one to three times per month. OOIDA indicated 
that among the members it surveyed, the 34-hour restart is the most 
consistently used feature of the current HOS rule, but it would be 
inaccurate for FMCSA to assume that all drivers are continuously 
maximizing use of the weekly 60 or 70 hours by using the 34-hour 
restart. NITL believes that substantial and/or continuous use of a 
``21-hour day'' by drivers is a hypothetical result, rather than a 
likely consequence of the 2003 rule in the real world. NITL goes on to 
state that as a practical matter drivers must take breaks and complete 
non-driving tasks over the course of the day, such as meals and 
mandatory vehicle inspections. IIHS stated that among the drivers it 
interviewed, more than 90 percent said they used the restart provision 
during 2004. IIHS said a large majority reported that the restart 
provision was part of their regular schedule. J.B. Hunt Transport 
reviewed the work record of 80 randomly selected over-the-road drivers 
for a 30-day period, and found that 74 percent of them used the 34-hour 
restart at least once during that period. On average, the drivers 
accumulated 62.25 hours per eight-day period. Werner Enterprises, Inc. 
said that its drivers use the 34-hour restart extensively and that they 
report feeling adequately rested after doing so. Schneider National 
said that 26.1 percent of its driver breaks are between 34 and 44 
hours.
Interaction of Weekly 60/7 and 70/8 Rules With Restart
    FMCSA explained in the 2005 NPRM that, under both the pre-2003 and 
2003 rules, most drivers are prohibited from driving after reaching a 
maximum of 60 hours of on-duty time in any consecutive 7-day period, or 
70 hours in any consecutive 8-day period. Of the 106 commenters who 
addressed the topic, 80 (75 percent) expressed opposition to the weekly 
limits and particularly their interaction with the restart provision.
    IIHS stated that, although the rule purports to maintain the prior 
60/70-hour limits on ``weekly'' driving, the restart provision actually 
allows drivers to log up to 88 hours of driving during an 8-day period 
(an increase of up to 30 percent), and up to 77 hours of driving during 
a 7-day period (an increase of up to 25 percent). IIHS claims that many 
drivers have dramatically increased their multi-day driving and work 
time, and they may do so week after week. Such a change should be 
allowed only if there is convincing scientific evidence that beginning 
another week of driving after such a short period of rest will not 
adversely affect safety.
    Public Citizen agreed that weekly driving and on-duty time would be 
radically increased under the rule. Under 7- or 8-consecutive-day 
limits, the most exhausted drivers, that is, those driving the daily 
maximums repeatedly, would in practice receive the longest weekly 
recovery period, while those driving and working less would reach the 
60-hour or 70-hour limits later in the week and have a shorter weekly 
recovery time. The 34-hour restart, on the other hand, has the effect 
of allowing truckers who maximize their driving to drive more per week 
with less required recovery time. Public Citizen said scientific 
studies show that as drivers log more hours on the road over multiple 
days, their performance declines. They concluded that drivers should 
not be able to accrue more than 60 hours of driving over 7 consecutive 
calendar days or more than 70 hours of driving over 8 consecutive 
calendar days. Fewer hours of driving would further improve safety.
    In contrast, Alertness Solutions stated that once any cumulative 
sleep debt has been erased through recovery sleep, an individual should 
be considered rested and without any acute sleep loss or sleep debt. 
From a physiological perspective, after a 34-hour restart period, a 
driver would be considered to have zero sleep loss, acute or 
cumulative, and be appropriately rested for duty. Alertness Solutions 
suggested that any subsequent duty hours accrued would be accrued from 
a rested or ``zeroed'' sleep loss calculation and added to the 
following total of work hours. Adding these subsequent work hours 
retroactively to a ``weekly'' total, after a recovery period, is 
misleading and inappropriate. Alertness Solutions said the weekly 
timeframe is an arbitrary constraint in this physiological context. 
While the total hours can be calculated to be higher in a ``week'' by 
adding retroactively, this ignores the physiological status of a driver 
who should be rested and ready for duty. In fact, the primary objective 
of a recovery or restart period is to ``zero out'' any

[[Page 50020]]

accumulated fatigue effects and have a rested operator prepared for 
duty.
Limits on Use of Restart
    The NPRM asked whether a driver who has already exceeded 60 hours 
on duty in 7 days, or 70 hours in 8 days, should be permitted to 
utilize the 34-hour restart at any time, or should instead be required 
to take enough days off duty to be in compliance with the 60-/70-hour 
provision before beginning the restart period. An Agency policy 
directive issued on November 25, 2003, provides guidance to roadside 
law enforcement officials on how to implement the 34-hour restart 
provision, when drivers have exceeded the 60/70 hour rule. The current 
policy guidelines require drivers to come into compliance with the 7/8-
day weekly duty time before applying the 34-hour restart provision.
    J.B. Hunt Transport argued that if the purpose is to punish the 
driver for working over the 60 or 70 hours (which they can do without a 
violation as long as they do not drive), then the driver who exceeds 
the 60 or 70 hours should be required to wait before using the restart 
provision. On the other hand, if the purpose is to ensure the driver is 
rested and safe, then many of the current studies and reports would 
support allowing the restart at any time. J.B. Hunt urged FMCSA to 
clearly indicate which of these two purposes it has chosen. The carrier 
said that the current regulatory wording is not consistent with the 
interpretive guidance that has been issued by the Agency.
    OOIDA questioned FMCSA's interpretation of the 2003 rule, which 
appeared to mean a driver who has driven for 59.9 hours in 7 days or 
69.9 hours in 8 days, respectively, could use the 34-hour restart, but 
a driver who has driven 60.1 or 70.1 hours would be required to go off 
duty for as many as three days before being allowed to return to duty 
or begin a 34-hour restart period. OOIDA said it is unaware of any 
study that supports the conclusion that drivers whose driving time is 
separated by just minutes need such dramatically different amounts of 
off-duty time to obtain restorative sleep. OOIDA asserted that a driver 
could obtain more than sufficient rest during a 34-hour restart 
regardless of whether the driver has exceeded the 60- or 70-hour rule. 
OOIDA asked FMCSA to withdraw its interpretation of the rule or to 
change the language of the rule. FedEx said that if a driver exceeds 
the rule's limits, the driver is in violation and should be held 
accountable. However, if a driver exceeds the rule's limits, either in 
the non-driving mode, which is legal, or in the driving mode, which is 
not, the 34-hour restart should reset the driver's clock to zero. FedEx 
noted that otherwise there is no foundation for enforcement. Because a 
driver is only required to carry the previous seven days' logs, it is 
impossible for a field enforcement officer to look back far enough to 
know if a reset was legitimate or not. Because a driver cannot legally 
drive after 70 on-duty hours in eight days or 60 on-duty hours in seven 
days, and given the impracticality of enforcement, FedEx Freight 
proposed that the restart be applicable to those cases in which a 
driver exceeds the 70-hour or 60-hour limit prior to the restart.
    Robert Transport suggested that a driver should be allowed to use 
the 34-hour restart in any circumstances. The carrier said that when 
drivers exceed their weekly limit, it is usually because of 
unpredictable events such as a snowstorm, an unusually long wait at a 
border crossing, or an excessive loading or unloading time. The carrier 
did not think that drivers should be penalized in these situations by 
having to wait before utilizing the restart.
    In contrast, the CHP asserted that drivers must be in compliance 
with the applicable cumulative total before using the restart 
provision. The CHP said that if a driver is allowed to use the 34-hour 
restart provision without regard to the 60/70-hour rules, the driver 
could easily work in excess of 98 hours in an 8-day period before 
driving is prohibited. A regional carrier also said that drivers should 
have to wait until they are below the 60/70-hour period before using 
the 34-hour restart. Otherwise, a carrier could send a long-haul driver 
back out on the road after only one day off, which the commenter said 
was insufficient time off.
Economic Impact of Eliminating Restart
    FMCSA requested comments on the impact of eliminating restart in 
terms of productivity, annual revenues, and operational costs. 
Responding to FMCSA's request, 68 commenters (49 drivers, 18 carriers, 
and one trade association) indicated that eliminating the 34-hour 
restart would have a negative economic impact on the trucking industry.
    J.B. Hunt Transport said that eliminating the restart provision 
would have a negative impact on the company, but the company had not 
quantified it. A sample of its drivers averaged 62 hours on duty in 8 
days, which indicated that the drivers were not using the restart 
provision to work the maximum number of hours possible. Given that 
fact, J.B. Hunt reported that eliminating the restart provision would 
not necessarily reduce the number of hours that its drivers worked each 
week. Roehl Transport estimated that eliminating the restart provision 
would reduce its productivity by 1 to 2 percent. The carrier believed 
that it would also incur higher fuel costs, because drivers would be 
waiting at truck stops more often and would burn the fuel to maintain 
comfortable cab temperatures. The carrier also thought that drivers 
would spend more money for meals and other living expenses, because 
they would be spending more time waiting while out on the road. A 
regional carrier of agricultural products noted that there are only 
certain times of the week when its drivers get tight on hours under the 
rolling weekly limits on hours. The carrier said that if the restart 
provision were eliminated, it would have trouble hiring drivers to work 
for only a few days a week. It also believed that its overhead costs 
would increase.
    Brandt Truck Line, a short-haul carrier, said that eliminating the 
restart provision would not affect local carriers operating under the 
60/70 weekly limit, but it would hurt the productivity of local 
operations working under the 70/8 limit. The carrier noted that those 
carriers either would have to revise their local Monday-to-Friday work 
schedules to be four days (14 hours each), or would have to reduce the 
hours of each 5-day driver from 14 hours per day to 11.67 hours per 
day. The carrier would then have to hire one additional driver for 
every seven drivers that it currently employs. Perishable Distributors 
of Iowa indicated that eliminating the 34-hour restart would hurt it 
financially because it would not be able to use the 16-hour rule as 
often. (As provided by Sec.  395.1(o)(3), drivers who have returned to 
their normal work-reporting locations for the five previous tours are 
allowed to operate up to the 16th hour once a week, unless they take a 
34-hour restart during that week.) The carrier said it would also have 
a labor issue, because it would have to shorten its routes and create 
more of them. The drivers would be working fewer hours, creating 
financial hardships.
Safety and Health Impact of Eliminating Recovery
    FMCSA asked about the health impact and the safety impact of 
eliminating the 34-hour restart. Both carriers and drivers said that 
elimination of the restart provision would be harmful to driver health.
    Werner Enterprises and Roehl Transport stated that elimination of 
the 34-hour restart would likely have a deleterious effect on driver 
health, and

[[Page 50021]]

would encourage drivers to adjust their work schedules to let them run 
every day without taking a day off. For long-haul drivers it would mean 
more non-productive sitting and waiting time during a week in a truck 
stop. The carriers asserted that wasting time results in a host of 
medical and life-style issues, including over-eating, frustration, 
stress, and a general feeling of job dissatisfaction in an industry 
where turnover is a significant issue. Drivers away from home during 
the week need to be allowed to work as much as they would like within 
the confines of safe operations. Maverick Transportation had no data to 
support a negative impact on health and safety but believed that 
elimination would have a big impact on driver lifestyle and morale. 
J.B. Hunt Transport said that removing the restart could have an 
adverse affect on drivers' health and could also negatively impact 
crash frequencies, because its drivers appear to use the restart as 
much to reduce stress and to obtain longer periods of rest when needed 
as they do to simply work and drive longer. Two carriers stated the 
restart impacts drivers' health positively because they start fresh 
after the period of time off that is spent at home the majority of the 
time. Two other carriers, however, noted that it would have no impact.
    One driver thought that eliminating the restart provision would 
contribute to older, experienced drivers leaving the industry. The 
resulting increase in the number of newer drivers would increase the 
number of crashes, fatalities, and injuries. Another driver said that 
elimination of the provision would increase the number of drivers who 
violate the HOS rules. Two drivers noted that the restart allows them 
to stay on a regular 24-hour cycle, and changing it would disrupt the 
cycle. Three drivers stated that elimination would increase driver 
stress. One driver stated that by the end of the 8-day cycle, drivers 
are working odd hours because they are trying to work around what they 
did 8 days before. If they start over after being off duty for 34 hours 
they will not be punished for working the week before. Without the 
restart they must sometimes drive a short day and work long hours 
during the early morning hours in order to make deliveries. This 
disrupts their sleep cycle and directly contradicts what the new 
regulations are supposed to correct.
    Finally, as described earlier under ``Opposition to Restart,'' 
several groups, including Public Citizen, AHAS, and IIHS expressed 
strong opposition to the restart provision.
FMCSA Response
    Based on the scientific data and comments it has received, FMCSA 
has decided to prohibit drivers from driving after reaching a maximum 
of 60 hours of on-duty time in any consecutive 7-day period, or 70 
hours in any consecutive 8-day period. The Agency will also allow any 
7- or 8-day period to end with the beginning of any off-duty period of 
34 or more consecutive hours. FMCSA has determined that a 34-hour 
recovery period permits a majority of drivers to have enough time for 
two uninterrupted nights of 8 hours recovery sleep before returning to 
work in a new multi-day duty period. While the research on adequate 
recovery periods is somewhat limited, there is general agreement that 
two nighttime periods (midnight to 6 a.m.) are sufficient for full 
recovery from fatigue. Data reviewed by FMCSA shows that 22 percent of 
CMV driving takes place at nighttime, between midnight and 6 a.m. 
[Campbell, K.L, & Belzer, M.H. (2000), p. 115]. Many of these drivers 
would have to sleep during the day. However, the 34-hour recovery 
period would give drivers who perform the other 78 percent of driving 
(between 6 a.m. and midnight) an opportunity to obtain two nights of 
recovery sleep prior to starting the next work week. In adopting the 
weekly limit and recovery provisions, the Agency considered all 
relevant research, appropriate economic factors, and comments received 
on the NPRM addressing driver health and public safety.
    In the 2000 NPRM, the Agency proposed to require a weekly off-duty 
period or ``weekend'' which would have imposed a regulatory requirement 
for a weekly off-duty period containing two midnight to 6 a.m. blocks 
for all CMV drivers (65 FR 25562). In the 2003 rule, FMCSA explained 
that it opted for a 34-hour restart provision in light of the concerns 
expressed by commenters that the proposed ``weekend'' requirement would 
increase daytime congestion and accident risks and produce irregular 
sleep schedules (68 FR 22477). Commenters pointed out that the 
``weekend'' proposal ``assumes that every driver is subject to weeklong 
sleep deprivation.'' FMCSA admitted that it ``may have overreached 
trying to prevent the most extreme abuses by imposing restraints on the 
whole driver population'' [Id.].
    Studies indicated that cumulative fatigue and sleep debt can 
develop over a weekly period, and at least two nights of sleep are 
needed to ``restore'' a driver to full alertness [Belenky, G., et al. 
(1998), p. 13; Jovanis, P.P., et al. (1991), p. 2; Linklater, D.R. 
(1980), p. 198; Williamson, A.M., et al. (1994), p. 104]. The Agency 
determined that the 34-hour recovery period, which is based on a full 
24-hour period plus an additional 10-hour period available for sleep, 
is the minimum restart which would provide adequate restorative rest. 
FMCSA explained in the 2003 rule that it considered a number of 
competing factors and opted for a uniform rule that ``represents the 
best combination of safety improvements and cost containment that can 
realistically be achieved'' (68 FR 22457). In the 2005 NPRM, FMCSA 
reiterated that, ``The 34-hour restart was considered as a flexible 
alternative to the ``mandatory weekend'' proposed in the 2000 NPRM * * 
* [70 FR 3348].
    The D.C. Circuit criticized FMCSA for neither acknowledging nor 
justifying that the 2003 rule ``dramatically increases the maximum 
permissible hours drivers may work each week'' (Public Citizen, at 
1222-1223). In the 2005 NPRM, the Agency explained that the restart 
provision provides an opportunity for increases in the total hours of 
permissible on-duty time in a 7-day period, after which a driver may 
not drive a CMV, from 60 hours to 84 hours. It also provides an 
opportunity for increases in the maximum driving time permitted in a 7-
consecutive-day period (from 60 hours to 77 hours). Likewise, the 
restart provision provides an opportunity for increases in the total 
hours of permissible on-duty time in an 8-day period, after which a 
driver may not drive a CMV, from 70 hours to 98 hours and, provides an 
opportunity for increases in the maximum driving time permitted in an 
8-consecutive-day period (from 70 hours to 88 hours). A number of 
advocacy groups argue that these extra on-duty and driving hours 
virtually guarantee that drivers are far more fatigued under the 2003 
rule than under the pre-2003 regulations.
    Several commenters argued against retaining the recovery period. 
Their comments can be placed into three related categories: (1) Two 
nights of sleep are needed for full recovery; (2) science does not 
support the 34-hour recovery period; and (3), the recovery period 
should be eliminated or increased in length due to the potential for 
drivers to significantly increase their daily and weekly working hours. 
The Agency decided to adopt a 34-hour recovery period based on an 
extensive scientific review of the literature, data, and comments. 
Adopting a recovery period is based upon seven main points: (1) Impacts 
of potentially longer weekly hours; (2) Operational data; (3) Economic 
impact of the rule; (4) Review

[[Page 50022]]

of the literature regarding recovery and fatigue; (5) Public comments; 
(6) Public safety and operational concerns and (7) Health impacts of 
eliminating or modifying the recovery provision.
Impacts of Potentially Longer Weekly Hours
    Some of the commenters paint a picture of drivers working every 
additional hour allowed by the 34-hour recovery provision, and 
accumulating dangerous levels of fatigue. As indicated by the docket 
comments of motor carriers and industry associations, these images have 
little to do with the real world. Information collected and analyzed by 
FMCSA shows that most drivers are taking longer recovery periods than 
the minimum 34-hour recovery period that FMCSA is establishing under 
this rule. FMCSA believes the average driver is not, and cannot 
realistically, drive and work the longer weekly hours, on a regular 
basis, as described by some of the commenters.
    The 2005 FMCSA Field Survey (see Section I.1) shows that between 
July 2004 and January 2005, 393 drivers used 1,411 recovery periods. 
The survey found that 95 percent of recovery periods exceeded 34 hours 
in duration. Figure 8 shows that 50 percent of the recovery periods 
were longer than 58 hours, in contrast to 5 percent that were only 34 
hours long. The data appear to confirm that, in fact, a majority of 
drivers are obtaining two midnight to 6 a.m. sleep periods.

                       Figure 8.--Recovery Periods
                              [Local & OTR]
------------------------------------------------------------------------
             Restart period  (hours)               Instances    Percent
------------------------------------------------------------------------
34..............................................          66  ..........
35 to 58........................................         635          45
>58.............................................         710          50
                                                 -------------
  Total.........................................        1411        100
------------------------------------------------------------------------
 Source: 2005 FMCSA Field Survey.

    In the 2005 NPRM, the Agency acknowledged that a driver using the 
34-hour recovery period could work a maximum of 77/88 driving hours or 
84/98 driving and other on-duty hours depending upon which weekly rule 
the motor carrier operated under (i.e., 60/7 or 70/8). It is highly 
unlikely that drivers could, in practice, continually maximize their 
driving and on-duty time and minimize their off-duty time. Many of the 
larger carriers that commented to the 2005 NPRM agreed that in most 
instances drivers do not consistently have the opportunity, nor are 
they taking it, to accumulate the maximum amount of driving and on-duty 
hours that are theoretically allowed under the 2003 rule. For example, 
J.B. Hunt Transport said that a sample of its drivers averaged 62 hours 
on duty per 8 days under the 2003 HOS rule, which indicates that the 
drivers are not using the restart provision to work the maximum number 
of hours possible. Werner Enterprises, Inc. also, said that there has 
been no significant change in the number of hours worked by its drivers 
as a result of the 34-hour restart. FMCSA's Field Survey showed the 
average weekly (7-day) hours worked by CMV drivers is 61.4 hours.
    To reach the maximum driving or driving and on-duty hours requires 
that nearly perfect logistics for picking up and delivering a load are 
routinely in place; in other words, total elimination of waiting time 
to load, mechanical and equipment problems, and traffic- and weather-
related delays. Additionally, as explained in this rulemaking, FMCSA 
and other independent survey data collected since the 2003 rule was 
adopted indicate that drivers are not, in fact, maximizing their 
driving hours or total on-duty time, nor do they routinely take the 
minimum number of off-duty hours. In view of these facts, drivers will 
not routinely accrue the maximum weekly driving and on-duty hours 
feared by some commenters.
    This is not surprising. As indicated above in section J.5, driving 
and on-duty hours under the 2003 rule would not be expected to increase 
suddenly unless there had been an equally sharp spike in demand for 
trucking services. Although the U.S. economy is expanding, there was no 
unprecedented eruption of demand for transportation in 2004 and 2005 
that might have overwhelmed the normal, measured growth of the motor 
carrier industry and forced drivers to maximize their work hours in 
order to handle a huge volume of new cargo. The data FMCSA has 
collected bear this out. While some drivers may occasionally drive the 
maximum hours allowed by the 34-hour restart rule, most will continue 
to work about the same number of hours they did before the 2003 rule. 
According to commenters, the great advantage of the restart provision 
is not the increased work hours it allows, which are not regularly 
used, but the scheduling flexibility it gives motor carriers and the 
added time at home it gives drivers.
Operational Data
    As mentioned earlier, the 2005 FMCSA Field Survey (see Section I.1) 
shows that between July 2004 and January 2005, 393 drivers used 1,411 
recovery periods. The survey found that 95 percent of recovery periods 
exceeded 34 hours in duration. Figure 8 shows that 50 percent of the 
recovery periods were longer than 58 hours, in contrast to 5 percent 
that were only 34 hours long. The data appear to confirm that, in fact, 
a majority of drivers are obtaining two midnight to 6 a.m. sleep 
periods.
    2004 FARS data suggest that fatigue-related crashes, as a percent 
of all fatal truck crashes, have decreased under the 2003 rule. 
Similarly, carriers commenting on the 2005 NPRM generally cite either 
stable or decreasing crash rates (see Section H-Crash Data). FMCSA 
agrees with many commenters that the limited data available does not 
provide a definitive picture of the impact the 2003 rulemaking has had 
on fatigue-related CMV crashes. However, the preliminary data reported 
and reviewed to date does suggest that fatigue related crashes have 
decreased as a result of the 2003 rulemaking.
Economic Impact of the Rule
    The safety and health effects of modifying or eliminating the 
recovery provision need to be weighed against the significant economic 
costs that would be incurred by the transportation industry. As 
discussed in detail in the RIA accompanying this rule, increasing the 
restart period to 44 hours would result in an extremely high cost 
relative to benefits. Specifically, the annual costs to implement a 44-
hour recovery period were estimated at approximately $600 million. The 
cost to eliminate the 34-hour recovery provision in isolation, or with 
no other HOS-related changes implemented, was even higher, with annual 
costs more than $1.5 billion from productivity losses to motor 
carriers, while safety benefits were estimated at less than one-tenth 
the cost. In summary, the cost to modify the recovery provision was 
estimated to be significant, which is due in part to its extensive use 
by the industry, as discussed in detail throughout this rulemaking.
    As discussed further in this section, an analysis of survey data by 
Campbell and Belzer [Campbell, K.L., & Belzer, M.H. (2000), p.115] 
found that the average commercial truck driver drives approximately 22 
percent of his or her weekly driving time during the midnight to 6:00 
a.m. period. While the economic impacts of restricting driving during 
the midnight to 6:00 a.m. period were not explicitly measured as part 
of this rulemaking, such a restriction would undoubtedly result in 
significant economic impacts to the motor carrier industry, given that 
22 percent of current driving time would have to be

[[Page 50023]]

shifted to the remaining 18 hours of the workday, or that period in 
which most highway congestion already occurs. These impacts would come 
in the form of both reduced safety benefits as well as new operational 
costs to carriers. Numerous comments submitted to the docket in 
response to the 2000 HOS NPRM spoke to this point. For instance, 
comments submitted by the National Private Truck Council, American 
Trucking Associations, Watkins-Shepard Trucking, the National 
Association of Small Trucking Companies, and many others, noted that 
restrictions placed on nighttime driving would force trucking companies 
to place more of their trucks on public roadways during the already 
congested daytime hours. Additionally, some carriers would have to 
purchase additional trucks that would be required to operate during the 
daytime period, in those instances where a single truck was previously 
utilized by two drivers operating on separate day and night schedules. 
As a result, all of these trucks would be operating at a portion of the 
day when traffic congestion is the worst, resulting in an increase in 
truck-related crashes and thereby offsetting any potential safety 
benefits resulting from a reduction in fatigue-related truck crashes 
from nighttime driving restrictions. Such a restriction would also 
impose major operational costs to those segments of the industry that 
use nighttime runs to support daytime operations. For instance, a 
sizeable portion of the driving done during the nighttime period is 
performed by line-haul drivers of LTL companies, which haul freight 
between terminals during the midnight to 6 a.m. period in preparation 
for local delivery services the following day.
Review of the Literature Regarding Recovery and Fatigue
    FMCSA is convinced that the combined impact of today's rule, 
including the 34-hour recovery period, increases the safety to CMV 
drivers and is not deleterious to their health. Other provisions of 
this rule restrict the total on-duty time to 14 hours that cannot be 
extended by breaks, require drivers to take 10 consecutive hours off 
duty before beginning a new duty period, and eliminate the split 
sleeper-berth provision, by requiring that drivers utilize one sleeper-
berth period of at least 8 hours. These provisions limit duty time, 
while affording ample time for drivers to obtain the 7 to 8 hours of 
sleep that the majority of the research indicates is sufficient to 
restore a driver to full alertness on a daily basis (see Combined 
Effects discussion, section J.11).
    FMCSA believes the 34-hour recovery period serves as an additional 
safety benefit that affords a majority of drivers two nights of sleep 
recovery, which should sufficiently enable drivers to eliminate or 
``zero out'' any cumulative fatigue that may occur over several days. 
While some research suggests that a 24-hour period is sufficient to 
reduce cumulative fatigue [Bonnet, M.H. (1994), p. 62], most research 
agrees that optimal recovery occurs when there are two consecutive 8-
hour sleep periods from midnight to 6 a.m. [Dinges, D.F., et al. 
(1997), p. 276; Rosekind, M.R. et al. (1997), p. 7.3]. Under the 34-
hour recovery period, 78 percent of the drivers will be able to obtain 
two consecutive nights of sleep, and those whose schedules do not 
permit night sleep will at least be provided with two 8-hour sleep 
periods and some schedule regularity. However, as stated by FMCSA's 
2000 NPRM expert panel, ``If the work shift ends late in the evening, 
e.g., 11:30 p.m., it is conceivable that the driver could be in bed by 
midnight if there is an adequate place to sleep nearby. Under these 
circumstances the total recovery time period could be as short as 31 or 
32 hours and still allow for two uninterrupted time periods between 
midnight and 6:00 a.m.''
    Additionally, nighttime drivers will be less fatigued on a daily 
and weekly basis, compared to the pre-2003 rule, through the combined 
effects of the provisions of the rule being enacted today (see Combined 
Effects, section J.11). While the two consecutive 8-hour sleep periods 
that some night drivers will utilize for sleep are not ideal, today's 
rule will limit the build-up of cumulative fatigue; hence, the two 8-
hour sleep periods give drivers an adequate opportunity to help 
minimize such acute and cumulative fatigue, regardless of their driving 
schedule.
    FMCSA has determined that, in general, recovery time periods must 
take into consideration the necessity for overcoming cumulative fatigue 
caused by sleep debt. [Dinges, D.F., et al. (1997), p. 267; Balkin, T., 
et al. (2000), p. ES-8; Belenky, G., et al. (2003), p. 11; Van Dongen, 
H.P.A, et al. (2003), p. 125] Fatigue resulting from sleep loss is 
usually characterized as acute, resulting from a single insufficient 
sleep period, or cumulative, resulting from two or more insufficient 
sleep periods [Rosekind, M.R., et al. (1997), p. 7.2]. Rosekind 
describes three types of sleep loss: ``Sleep loss can occur either 
totally or as a partial loss. Total sleep loss involves a completely 
missed sleep opportunity and continuous wakefulness for about 24 hours 
or longer. Partial sleep loss occurs when sleep is obtained within a 
24-hour period but in an amount that is reduced from the 
physiologically required amount or habitual total. Sleep loss also can 
accumulate over time into what is often referred to as ``sleep debt.'' 
Sleep loss, whether total or partial, acute or cumulative, results in 
significantly degraded performance, alertness and mood'' [Id.].
    Under today's rule, most drivers have an adequate opportunity to 
limit the accumulation of fatigue. Ten hours off duty gives drivers 
enough time for 7-8 hours of sleep. In addition, adopting a non-
extendable 14-hour duty tour (reduced by one or more hours from the 
pre-2003 rule) will also limit the accumulation of fatigue. The off-
duty and duty-tour provisions collectively help ensure that drivers can 
maintain a 24-hour cycle. Comments also support the notion that the 
restart helps drivers stay on a 24-hour circadian cycle. In addition, 
today's rule moves drivers from an 18-to 21-hour driving time/off-duty 
cycle, which is far closer to a 24-cycle than previous rules achieved, 
thereby reducing the severity of a backward rotating schedule, 
resulting in less driver fatigue. Further, the revised sleeper-berth 
requirement provided by this rulemaking also gives drivers the 
opportunity to obtain 7-8 hours sleep. These provisions, together with 
the 34-hour recovery period, are more than adequate to allow drivers to 
return to baseline alertness levels.
    This provision protects a majority of drivers because 78 percent of 
driving time occurs between 6 a.m. and midnight [Campbell, K.L., & 
Belzer, M.H. (2000), p. 115]. Specifically, the 10 hours off duty 
coupled with the reduced, non-extendable 14-hour duty tour will provide 
drivers the opportunity for sufficient recuperative rest on a daily 
basis to drive and work the daily maximum limits allowed by today's 
rule. Therefore, the recovery period serves as an added safety net to 
protect drivers from instances when cumulative fatigue does occur over 
a 7- or 8-day period.
    Research concerning specific recovery periods is limited. Most 
sleep researchers agree the ideal recovery time for cumulative sleep 
loss would be an opportunity to obtain sleep during two uninterrupted 
periods from midnight to 6 a.m. [Belenky, G., et al. (1998), p. 13; 
Bonnet, M.H. (1994), p. 62].
    The 2003 rule treats daytime and nighttime driving equally, both in 
terms of hours permitted and required recovery time. While it is 
recognized that daytime sleep obtained by night

[[Page 50024]]

drivers is not equivalent in quality to night sleep [Akerstedt, T. 
(1997), p. 105] research concerning specific recovery requirements, 
particularly for night drivers, is limited. Working/driving during the 
night, especially midnight to 6 a.m., has the combined effect of 
affording poorer quality sleep (daytime sleep) and requiring the driver 
to work and drive during the time when the physiological drive for 
sleep is strongest. In preparation for the 2000 NPRM, FHWA convened a 
panel of experts to advise the Agency on science associated with 
various aspects of the proposed hours of service regulation.
    With respect to night driving, the Expert Panel, after reviewing 
the relevant literature, came to the conclusion that accident risk is 
substantially higher during nighttime hours, independent of the length 
of time on the job, and this elevated risk cannot be ignored. The 
expert panel also determined that driving between the hours of midnight 
and 6:00 a.m. is associated with as much as a 4-fold or more increase 
in fatigue-related crashes, because our body clock is ``set'' to wake 
us up in the morning and to send us to sleep at night. The panel 
concluded that even when adequate sleep time is available during the 
day, the time actually spent sleeping is less than at night. Shift work 
and night work are associated with acquisition of less sleep, even when 
night work is permanent. The panel surmised that this is caused by 
disrupting effects of circadian cycles and that sleep obtained is not 
only reduced in length, but also poorer in quality.
    The science supports the notion that drivers should be provided 
recovery periods after a sustained period of daily work to compensate 
for any build-up of cumulative fatigue or sleep deprivation [Belenky, 
G., et al. (1998), p. 12]. There is, however, no scientific basis for 
concluding that every driver, or even every nighttime driver, is sleep 
deprived. As mentioned, FMCSA has determined that the 34-hour recovery 
period gives the majority of drivers the opportunity to obtain two 
uninterrupted nights of 8 hours of recovery sleep.
    However, other sleep researchers indicate that recovery to baseline 
performance levels can be achieved with as little as 24 hours recovery 
time [Alluisi, E.A. (1972), p. 199; Feyer, A.M., et al. (1997), pp. 
541-553; O'Neill, T.R., et al. (1999), p. 2]. Smiley and Heslegrave 
[Smiley, A., & Heslegrave, R. (1997), p. 8], in their literature review 
regarding 36-hour recovery, identified a study that suggests one day 
off is insufficient for night workers to pay off the accumulated sleep 
debt from 5 days of work.
    IIHS and Elisa Braver cited Park et al. (2005), as a study that 
purportedly showed that 34-hour restart is an insufficient period for 
recovery. The Park study is an analysis of pre-existing crash and non-
crash data representing an estimated 16 million vehicle miles of 
travel. The study reported, in part, that there is some evidence, 
although not persuasive, that there may be risk increases associated 
with significant off-duty time, in some cases in the range of 24-48 
hours. The study suggests that ``restart'' programs should be 
approached with caution. Two sets of models were estimated with the 
data. Model 1 was developed to assess the effect of driving time which 
is divided into 10, one-hour periods with the first hour serving as the 
baseline. The second model retained driving time and added as 
covariates 43 driving schedules manually derived and developed by 
cluster analysis. The most significant deficiency in the study was that 
there were a number of HOS rule changes in 2003 that make the data not 
applicable. First, the off-duty time has increased from 8 to 10 hours 
and the on-duty time went from 15 plus hours per day to only 14 hours 
per day. Both of these changes were intended to reduce any cumulative 
fatigue that might result. Second, the study and particularly the 
models used could have been significantly improved if the study had 
undergone a peer review process. Lastly, the authors concluded that 
``there is some evidence, although it is far from persuasive, that 
there may be risk increases associated with significant off-duty time, 
in some cases in the range of 24-48 hours'' [Park, S-W., et al. (2005), 
p. 16]. The Agency has examined the study, and like its authors, has 
concluded that the findings are not persuasive that a shorter recovery 
period presents greater risk to CMV safety.
    Additionally, IIHS cited the Wylie [Wylie, C.D., et al. (1997)] 
study as stating that 36-hour recovery was an insufficient period to 
``zero out'' any cumulative fatigue. This study was also based on the 
pre-2003 rule--drivers operating under the new rule should be less 
susceptible to cumulative fatigue. The Wylie study was a small 
demonstration study of a methodology that could be used to evaluate 
drivers' recovery periods. Twenty-five drivers in small groups (4-5 
drivers each) were used to evaluate different recovery periods (12, 36, 
and 48 hours) and driving time. None of the recovery periods examined 
were found to be of sufficient length for driver recovery. The study 
concluded that the small subject sample limited the ability to make 
reliable estimates of observed effects [Wylie, C.D. (1997), p. 27]. 
Given the authors' conclusion, the Agency has not relied upon the Wylie 
study to evaluate the adequacy of the 34-hour recovery period.
    As explained earlier, few studies address the effect of recovery 
periods between work periods spanning multiple days, such as a workweek 
[O'Neill, T.R., et al. (1999), p. 2; Wylie, C.D., et al. (1997), p. 27; 
Smiley, A., & Heslegrave, R. (1997), p. 14]. After reviewing the 
studies relevant to the 34-hour recovery period, as cited in the 2003 
rule and those submitted by commenters to the 2005 NPRM, the Agency has 
determined that current scientific evidence is limited. Therefore, 
changes in HOS regulations must, in addition to considering the 
relevant science and research, be accompanied by sound regulatory 
evaluation that encompasses all relevant issues, including public 
interest, cost, and public safety.
    The Agency considered implementing a restart period of 44 hours. 
This would give more drivers, specifically nighttime drivers, an 
opportunity to be off duty for two nighttime periods between midnight 
and 6 a.m. However, it would also encourage drivers to operate on a 
rotating shift, not to mention shifting more drivers to day time, 
thereby increasing traffic during the day. A forward-rotating schedule 
would result in a driving schedule that would cause a driver to begin 
working at a later time of day than the previously used weekly 
schedule. Therefore, toward the end of each work week, the driver would 
begin work later and later each day, ultimately shifting the driving 
and on-duty time into the nighttime hours. Consequently, the added 
recovery hours would have a negative impact on a driver's circadian 
cycle.
    The Agency attempted to determine whether the added hours of 
recovery, through the use of a 44-hour recovery period, created a net 
benefit in reducing fatigue compared to the potential negative impact 
on circadian rhythm of establishing a rotating schedule. The Agency has 
determined there is no conclusive scientific data to guide it in 
determining which factor (recovery time vs. circadian disruption) is 
more effective in alleviating fatigue. In sum, in deciding to adopt a 
34-hour recovery period, the Agency considered that compliance with a 
34-hour recovery period results in a CMV driver restarting work at 
approximately the same time of day as his or her prior shift. The 34-
hour recovery period also avoids the shifting of daytime to nighttime 
schedules,

[[Page 50025]]

which research indicates can disturb the circadian rhythm and decrease 
alertness.
Public Comments
    In the 2005 NPRM, the 34-hour recovery period received support from 
more comment letters than any other provision (591 approved versus 109 
disapproved). The commenters said that the 34-hour recovery period 
makes scheduling much easier than working with the old rolling weekly 
limits. Comments also indicated that 34 hours off duty are long enough 
to allow recovery (111 of 130 comment letters that addressed the 
issue). According to a 2004 survey, among 31 fleets that responded, the 
34-hour restart is the most utilized feature of the 2003 rule. The 
survey, titled ``A Survey of Private Fleets on their Use of Three New 
``Hours of Service Features','' conducted by Stephen V. Burks of the 
University of Minnesota, found that ``most widely used among survey 
respondents is the 34-hour Restart, which is employed on average of 61 
percent of the runs of firms in the sample'' [Burks, S.V. (2004), p. 
2]. Additionally, driver surveys have shown time to spend at home and 
with family was identified as a major priority [Belenky, G., et al. 
(1998), p. 41].
Public Safety and Operational Concerns
    As mentioned earlier in this section, many comments to the 2000 
NPRM suggested that by requiring all drivers to take two midnight to 6 
a.m. recovery periods, FMCSA would be increasing the number of heavy 
vehicles operating in daytime traffic. The commenters stated that this 
would create greater hazards to public safety. While ideally all CMV 
drivers can benefit from obtaining two nights of sleep, FMCSA continues 
to believe, as stated in the 2003 rule (68 FR 22477), that restricting 
nighttime driving by mandating a midnight to 6 a.m. off-duty period for 
all CMV drivers would have the unintended consequence of substantially 
increasing the number of heavy vehicles in daytime traffic, creating 
greater hazards for the average motorist simply because of the higher 
density of vehicles.
    The Agency also took into consideration that not all motor carrier 
operations work on a ``fixed and recurring 7-day period,'' instead 
having intense days of work followed by slack times, and that other 
operations can be disrupted by weather. For example, one commenter 
discussed how weather affects the logging transportation industry. The 
commenter explained that a CMV driver might begin the workweek on 
Monday, fully rested and work a full 14-hour day, which is interrupted 
by a full day of rain (Tuesday). The commenter explained the 34-hour 
recovery period allows the CMV driver to resume work on Wednesday and 
be able to work in compliance with the regulations to accomplish the 
work required during that work week. The Agency has decided the 34-hour 
recovery gives motor carriers and drivers the option of restorative 
rest during the times work is not available or is interrupted. Given 
that the recovery provision can be taken at any time, it is a flexible 
safety tool that can be used by drivers as an added restorative safety 
measure.
Health
    The 34-hour recovery provision has turned out to be one of the most 
popular provisions of the 2003 rule among CMV drivers. Several carriers 
indicated they now see drivers proactively scheduling extended off-duty 
recovery periods into their workweek and returning after these extended 
periods with ``positive attitudes and appearing rejuvenated,'' which 
promotes improved driver health.
    FMCSA examined the effect of the new rule on driver work hours by 
comparing survey data obtained before and after the 2003 rule was 
implemented. A detailed discussion of those results along with 
confirming data from multiple carriers can be found in Section E'' 
Driver Health. These data show that CMV drivers are not working longer 
hours as a result of the 2003 rule than they did under the pre-2003 
rule. In addition, the Field Survey conducted by FMCSA showed that many 
drivers are taking recovery periods considerably longer than the 34-
hour minimum. Fifty percent of the drivers were found to have taken 58-
plus hours of recovery time per week and 67 percent of drivers took 44 
hours recovery time per week, as explained in Section I.1.
    One of the reasons that the 34-hour recovery rule is so popular 
among drivers is that it appears to provide for longer blocks of 
consecutive hours away from work than the pre-2003 rule provided `` to 
rest, to be with family, and to recover prior to the start of the next 
work week. In a survey of its membership, OOIDA asked ``Do you get more 
time at home under the new HOS regulation?'' Twenty percent of OOIDA 
drivers responded ``yes''--that they were getting more time at home as 
a result of the 2003 rule. A slightly higher percent (21 percent) of 
long haul drivers responded that they were getting more time at home 
compared to short-haul drivers (18 percent). The survey question's 
wording did not allow for an examination of how many drivers may be 
spending less time at home as a result of the 34-hour recovery. It 
appears that for some drivers the 34-hour recovery period may allow 
more time at home and provide for greater stabilization of family life. 
The impact of these factors is difficult to quantify from a driver 
health perspective, but an improved quality of life may lead to 
improved health. Few research studies have been conducted that address 
this particular issue. (See Combined Effects--Section J.11, for further 
discussion.)
    As explained earlier, the 34-hour recovery period provides the 
potential opportunity for drivers to increase their weekly driving and 
on-duty time. The National Institute of Occupational Safety and Health 
(NIOSH) reviewed the relationship between long hours and worker health. 
It generally concluded that long work hours are associated with poorer 
health, increased injury rates, more illnesses, or increased mortality. 
However, the NIOSH review of the literature on long work hours also 
documented a significant lack of data on general health effects. NIOSH 
raised doubts about the strength of its own conclusions, stating that 
``research questions remain about the ways overtime and extended work 
shifts influence health and safety.'' NIOSH did, however, examine three 
studies that identified the relationship between long shifts, those 
typically worked by a CMV driver, and health or performance. The 
results are documented in Section E--Driver Health.
    Research indicates that psychological factors do play a role in the 
health of individuals, including CMV drivers. For example, CMV drivers 
generally want the freedom to manage their workplace and schedule. 
Given the shortage of CMV drivers, the ready availability of jobs, and 
the high level of reported driver turnover, it is unlikely that any one 
employer could require a driver consistently to work the maximum hourly 
limits available in the 2003 rule or today's rule--unless a driver 
chose to do so. In other words, working long hours is an individual 
choice. A driver has the right to choose to work longer hours to earn 
greater pay as long as he or she can operate a CMV safely. Survey data 
presented and discussed earlier, from multiple sources, indicate that 
contrary to the concerns expressed by some commenters, drivers are, in 
fact, not driving more under the 2003 rule than they were under the 
pre-2003 rule. Instead, the 34-hour recovery period is being used in a 
positive way, i.e., more driver time with family and greater 
operational flexibility and productivity.

[[Page 50026]]

    Two studies in the NIOSH review found that compensation has a 
strong effect on the perceived impact of long working hours. Siu and 
Donald [Siu, O.L., & Donald, I. (1995), p. 30] and van der Hulst and 
Geurts [van der Hulst, M., & Geurts, S. (2001), p. 227] suggested that 
compensation may reduce the adverse effects of long work hours. The Siu 
and Donald study [p. 48] reported a relationship between perceived 
health status and overtime pay. Men from Hong Kong who received no 
payment for overtime work had more health complaints than men who 
received payment for overtime work hours. In addition, the van der 
Hulst and Geurts study [p. 227] examined the relationship between 
reward and long working hours in Dutch postal workers. This study also 
showed that if workers are compensated, they are able to work longer 
hours without negative consequences to their psychological health [Id., 
p. 237].
    Few studies have examined how the number of hours worked per week, 
shift work, shift length, the degree of control over one's work 
schedule, compensation for overtime, and other characteristics of work 
schedules interact and relate to health and safety [Caruso, C.C., et 
al. (2004), p. 30.] Van der Hulst, who also conducted a review of 
research literature on long work hours, concluded ``that the evidence 
regarding long work hours and poor health is inconclusive because many 
of the studies reviewed did not control for potential confounders. Due 
to the gaps in the current evidence and the methodological shortcomings 
of the studies in the review, further research is needed'' [van der 
Hulst, M. (2003), p. 171].
    There is no conclusive research showing that long hours alone are 
associated with poor health, especially when taking into account 
individual choice, compensation, and degree of control over one's work 
schedule. Also, given the results of FMCSA's 2005 survey of driver 
hours, it is unlikely that the current HOS rules increase the overall 
number of hours a driver actually works. In short, given current 
knowledge, there is no clear evidence that the work hours allowed by 
today's rule will have any impact on driver health.
Limits on the Use of the 34-Hour Restart Period
    During the implementation of the 2003 final rule, several 
enforcement issues were identified and subsequently addressed through 
an Agency policy directive dated November 25, 2003. The policy memo 
provides guidance to roadside law enforcement officials on how to 
implement the 34-hour restart provision, when drivers have exceeded the 
60/70 hour rule. Regulatory officials, motor carriers and CMV drivers 
complained that the interpretive guidance provided by FMCSA was not 
consistent with the wording of the regulation.
    After reviewing the comments and considering all enforcement 
remedies available to Federal and State regulatory agencies, FMCSA has 
decided that if a driver has exceeded the 60/70-hour rule, the driver 
does not have to come into compliance with the 60/70-rule before 
utilizing the 34-hour recovery period. However, the driver could be 
subject to appropriate penalty provision as provided by 49 CFR Part 386 
for violating the provisions of 49 CFR 395.3(b). FMCSA is considering 
additional enforcement remedies in its EOBR rulemaking for both motor 
carriers and CMV drivers that violate the provisions of 49 CFR 
395.3(b).
    Questions also arose concerning the appropriate amount of time a 
driver must be placed Out-Of-Service (OOS) prior to being allowed to 
drive again for exceeding the 60/70-hour rule in 7/8 days. The length 
of an OOS period required to bring a driver back into compliance is 
currently determined based on the number of hours the driver is in 
excess of the rule. The Agency did change this practice with the 
implementation of the 2003 final rule.
    In this rulemaking FMCSA has decided the driver should be placed 
OOS for the minimum amount of time necessary to bring the driver into 
compliance with the provisions of Sec.  395.3(b), or be allowed to take 
a 34-hour recovery period, whichever is less. As explained earlier in 
this preamble, a 34-hour recovery period will allow a driver ample 
opportunity to obtain sufficient rest, even if the driver has exceeded 
the 60 or 70 hour limits.
Conclusion
    In adopting a 34-hour recovery period, FMCSA has taken into account 
the weekly accumulation of driving and on-duty time allowed during each 
7- and 8-day period, the adequacy of the 34-hour recovery, the cost/
benefit ratio, the overwhelming support of the 34-hour recovery by the 
transportation industry, including motor carriers and drivers, the 
long-term effect on driver health, and the overall safety aspects of 
retaining this provision.
    FMCSA is charged with creating minimum safety standards for CMV 
drivers under the Motor Carrier Safety Act of 1984 [49 U.S.C. 
31136(a)]. The Agency is also required to consider the economic costs 
and benefits that the rule would impose on the trucking industry and 
the public [49 U.S.C. 31136(c)(2)(A) and 49 U.S.C. 31502(d)]. As a 
regulatory Agency, FMCSA must sift through general, and often 
conflicting, scientific data and attempt to apply it ``in the real 
world.''
    When considering previous studies cited in the 2003 rule in support 
of the 34-hour recovery period and subsequent studies cited in comments 
to the 2005 NPRM, the Agency determined that, in light of the 
scientific evidence, FMCSA's best judgment is that 34 hours provides a 
minimum amount of time for a majority of drivers to recover from any 
cumulative fatigue that might occur during any multi-day duty period.

J. 9. Sleeper-Berth Use

    Under the 2003 rule, drivers are permitted to accumulate the 
minimum off-duty period of ten consecutive hours four separate ways: 
(1) A minimum of 10 consecutive hours off duty; (2) A minimum of 10 
consecutive hours in a sleeper berth; (3) By combining consecutive 
hours in the sleeper berth and off-duty time that total 10 hours; or 
(4) By combining two separate sleeper berth rest periods totaling at 
least 10 hours, provided that neither period is less than 2 hours 
(split sleeper berth exception).
    Although FMCSA has found that drivers need 10 consecutive hours of 
off-duty time to obtain the necessary 7 to 8 hours of restorative sleep 
per day, the split sleeper berth exception in the 2003 rule allows a 
driver to accumulate his or her sleep in two separate periods that 
totaled at least 10 hours.
    Splitting sleep into short periods is a concern. One study, ``The 
Effects of Sleep Deprivation on Performance During Continuous Combat 
Operations'' [Belenky, G., et al. (1994), p. 129)], found that ``Brief 
fragmented sleep has little recuperative value and is similar to total 
sleep deprivation in its effects on performance.'' While this study was 
conducted on soldiers attempting to sleep in busy, noisy command 
centers, it may still be relevant in some cases when discussing sleeper 
berth rest, depending upon the environment in which the vehicle is 
parked and the physical condition of the sleeper berth or truck-tractor 
cab.
    Sleeping in a sleeper berth has been studied as it relates to truck 
fatalities. A study by the Insurance Institute for Highway Safety 
[Hertz, R.P. (1988), p. 7] found that splitting sleep into two sleeper 
berth periods without having 8 consecutive hours in the sleeper berth 
``increased the risk of fatality over twofold.'' Hertz also found that 
split

[[Page 50027]]

sleeper berth use increased fatality risk ``in all analyses except 
those limited to urban crashes and local pick-up and delivery 
crashes.'' [Id., p. 9]
    In a 1996 safety study, the NTSB found that the duration of the 
most recent sleep period in the 24 hours prior was the most important 
factor for predicting a fatigue-related crash [Id., p. 51]. The NTSB 
also noted that the hours of service regulations at the time (8 hours 
off-duty) did ``not provide the opportunity to obtain an adequate 
amount of sleep'' and recommended that the use of split sleeper berth 
time be eliminated [Id.]
    FMCSA has determined that the available science and literature do 
not support the continued use of the current split sleeper berth 
provision. Surveys indicate that only a small percentage of drivers 
split their sleeper berth time to obtain the necessary off-duty time. 
An OOIDA survey conducted in 2004 indicates that their members use a 
split sleeper berth 13 percent of available workdays each month. A 
survey of private motor carriers [Burks, S.V. (2004), pp. 3-4] 
indicates that split sleeper berth use in the private fleets is on 
average about twice as high as the OOIDA number. However, Burks pointed 
out that of the private firms that use sleeper berths ``half the sample 
utilizes the [split] [s]leeper berth 2% of the time or less'' [Id., p. 
3].
    The split sleeper berth exception is also problematic from a driver 
health standpoint. There is a growing body of research demonstrating 
that sleep periods of 4 hours, or less, can result in a number of 
adverse physiologic medical symptoms or conditions that result from 
having a specific disease, including reduced glucose tolerance, 
increased blood pressure, activation of the sympathetic nervous system, 
reduced leptin levels, and increased inflammatory markers [Alvarez, 
G.G., & Ayas, N.T. (2004), p. 59]. Consistent with these studies, 
epidemiologic research demonstrates that short sleep duration is 
modestly associated with symptomatic diabetes, cardiovascular disease, 
and mortality [Id.]. Given the uncertainty with regard to combining two 
sleep periods these studies suggest that drivers need one period of 
sleep that is between 7 to 8 consecutive hours daily in order to 
maintain a healthy lifestyle.
Comments
    Approval of the Split Sleeper-Berth Exception. The FMCSA asked 
commenters to address the fundamental question of whether the Agency 
should eliminate the split sleeper-berth exception and require drivers 
to take 10 consecutive hours off duty (either in a sleeper berth or in 
combination with off-duty time).
    A total of 130 commenters expressed general approval of the split 
sleeper-berth provision. Of these, four were trucking associations 
(ATA, OOIDA, Associated Petroleum Carriers, and Corporate 
Transportation Coalition), 42 were carriers, 80 were drivers, and four 
were private citizens. Commenters stated that the provision allowed 
drivers to take naps when needed, and to avoid traffic congestion.
    Maverick Transportation, C.R. England, OOIDA, and Werner stated 
that the split sleeper-berth exception is the only way a driver can 
take a needed nap without being penalized. Werner noted that over 80 
percent of its drivers use the sleeper berth on a regular basis. C.R. 
England described a study of split sleeping time which indicates that 
total sleep time per 24 hours is the most important determinant of 
performance, and that sleep can be split into an anchor period of at 
least 6 hours sleep and another period of 2 hours with a combined 
effect roughly equivalent to the performance and alertness that is 
obtained from a continuous 8 hour sleep period. The commenters 
concluded that the sleeper berth, when used properly, did not reduce 
drivers' ability to obtain adequate restorative sleep.
    Disapproval of the Split Sleeper-Berth Exception. Almost as many 
commenters (a total of 112), however, expressed general disapproval of 
the split sleeper-berth exception. These included AHAS, Public Citizen, 
18 carriers, 86 drivers, the Georgia Department of Motor Vehicle 
Safety, and four others. The reasons for disapproval varied. Several 
commenters noted that the rule was an invitation for cheating, while 
others stated that split sleeper berth periods do not provide enough 
rest.
    Public Citizen strongly opposed the split sleeper-berth provision 
and stated that the exception allowed solo drivers to divide their rest 
time any way they wanted, despite FMCSA's repeated findings that 
drivers need 8 hours of uninterrupted sleep. They noted that the 
increase in minimum off-duty time in the current HOS rule from 8 to 10 
hours was based on FMCSA's assertion that a driver with only 8 hours of 
off-duty time generally obtained only 5 hours of sleep, and cited 
FMCSA's statements that studies point specifically to increased crash 
risk after fewer than nine hours of off-duty time. They noted that 
FMCSA has acknowledged that research from all transportation modes 
suggested a need for off-duty periods of 10 to 16 hours to ensure the 
needed block of sleep. They stated that studies are unanimous that 
drivers get both less sleep and lower quality sleep when it is taken in 
two separate sleeper-berth or other rest periods. Public Citizen cited 
a study suggesting drivers usually got no sleep during logged sleeper-
berth periods.
    Public Citizen noted that a 1997 OOIDA study showed that nearly 75 
percent of drivers took their off-duty time in a single block. The 
study showed that those who split their sleeper-berth breaks on average 
took two 4-hour breaks. Public Citizen recommended that solo drivers 
should take at least 10 consecutive hours off in a single block of 
time, regardless of where the time was spent.
    The Minnesota Trucking Association recommended that the split 
sleeper-berth option be changed to reduce the minimum time block to 1 
hour, and to allow up to three periods for the calculation of the total 
split sleeper-berth time.
    Minimum Necessary Length of Split-Sleeper-berth Periods. The Agency 
requested information on the minimum time in each of two split-sleeper-
berth periods necessary to provide restorative sleep. Figure 9 provides 
the breakdown of responses to FMCSA's question on minimum sleeper-berth 
periods.

      Figure 9.--Commenters: Suggested Minimum Sleeper Berth Period
------------------------------------------------------------------------
           Minimum time             Carriers   Drivers        Other
------------------------------------------------------------------------
< 2 hours.........................         11         30  1
2-3 hours........................          3         11
3-4 hours........................          2          2
4-5 hours........................          5          7  1
5-6 hours........................  .........          6
6-7 hours........................  .........          1
7-8 hours........................          1          4  1 (NTSB)
------------------------------------------------------------------------

    Alertness Solutions reported research showing that obtaining 2 
hours less sleep than needed (for an average adult this equates to 
about 6 hours of sleep) produces a reduction in performance and 
alertness. The data showed that obtaining a total of 8 hours of sleep 
per 24-hour period is critical. However, sleep can be split into an 
``anchor period'' of at least 6 hours of sleep and a period of 2 hours 
of sleep at another time with a combined effect of performance and 
alertness that is roughly equivalent to that obtained from a continuous 
8 hour sleep period. Rosekind of Alertness Solutions concluded that 
translating these scientific results into operational practice would 
suggest that an ``anchor sleep opportunity'' of 6.5 hours and another 
sleep opportunity of 2 hours would likely provide the minimum

[[Page 50028]]

number of sleep hours needed to maintain a performance level equivalent 
to one 8-hour sleep period. He said no data indicate whether the order 
of the two split sleep periods would have a significant effect. He also 
noted that a sleeper berth provides significant flexibility and 
proximity that should be regarded when determining the role and 
opportunity for the use of split sleep. Although there could obviously 
be a variety of combinations that might be considered for split sleep, 
Rosekind concluded that two factors are critical. First, at least one 
sleep period should provide sufficient opportunity for a minimum of 6 
hours of sleep. Second, the combined total sleep obtained in the split 
sleep periods should approximate 8 hours. AHAS, however, criticized 
Rosekind for ignoring contradictory research that the split sleeper 
berth periods do not provide sufficient rest and performance 
restoration.
    Several carriers reported on the sleeper-berth patterns of their 
drivers. Yellow Roadway reported that 70 percent of its team drivers 
split their sleeper-berth time into two 5-hour periods. C.R. England 
said its teams split 5 and 5 or 6 and 4; its solo drivers usually split 
6 and 4 or 7 and 3. Overnite reported that its teams split 5 and 5, 
explaining that this pattern means that a driver never drives more than 
5 hours at a time. Brink Farms and a driver also supported a 5-hour 
minimum. Schneider said it limits solo drivers to 8 and 2 only and 
believes the foundation period for solo drivers should be 8 hours. 
Schneider provides its team drivers more flexibility.
    Some carriers suggested mandatory split sleeper periods. Schneider 
recommended that the total off-duty time be 9 hours, with an 8 and 1 
split, citing a study that advised strategic naps of no more than 45 
minutes. FedEx cited a study that showed that two periods totaling 7.4 
hours resulted in performance equal to that obtained from a single 8.2 
hour sleep period. J.B. Hunt also cited the same study to argue for an 
anchor period of 6 hours, which could be combined with another 2 hours 
of sleep and 2 hours off duty.
    Most trucking associations endorsed a 5 and 5 split. ATA stated 
that 5 and 5 has worked for team drivers and recommended continuation 
of the 2003 rule. The Motor Freight Carriers Association (MFCA) also 
supported 5 and 5 splits, and stated that company crash data indicate 
that this does not result in an unsafe operating environment. MFCA 
stated that a rule change that reduced team flexibility could have a 
negative impact on driver safety, but provided no supporting data for 
the assertion.
    The California Highway Patrol (CHP) stated that the minimum 
sleeper-berth period should be at least 5 hours; periods of less than 5 
hours should count against the 14-hour day. CHP also asked that 
``qualifying sleeper-berth period'' be defined.
    The NTSB essentially rejected the split sleeper-berth option, 
arguing that FMCSA should eliminate any provision that provides for a 
daily sleep period of less than 8 continuous hours. The current split 
exception allows for less than 8 hours of sleep in conditions that are 
not optimal for sleeping, it said.
    Impact of Increasing Minimum Split Time for Longer Periods. FMCSA 
asked what the impact would be on driver health, the safe operation of 
CMVs, and economic factors, if the Agency were to retain the split-
sleeper-berth provision, but require that one of the two periods be at 
least 7, 8, or 9 hours in length. Four carriers, the California Highway 
Patrol, and 25 drivers responded to this question. Eight commenters 
(seven drivers and a carrier) stated that a single break of 7 hours 
would be sufficient and no additional sleeper-berth period would be 
needed. Seven commenters (six drivers and McLane Company) supported 7 
hours plus another break, not necessarily in the berth. Four drivers 
and McLane also argued that everyone is different and a single rule is 
not appropriate.
    The California Highway Patrol stated that requiring 7, 8, or 9 
hours as a minimum for one of two qualifying sleeper-berth periods 
would allow a driver to rest only 1, 2, or 3 hours (during the second 
period) and then drive for an extended period of time. This might also 
lead to disruption of the 24-hour cycle upon which the regulations are 
based. Brink Farms argued that, for teams, an 8 and 2 split would do 
more harm than good and supported a 5 and 5 split for teams. It also 
supported allowing the second period to be out of the berth.
    Yellow Roadway did not agree that 7 or more hours in the berth are 
the equivalent of 10 hours off duty. The 10-hour period gives a driver 
a chance for sleep and other personal time. A split with less than a 
10-hour total would put the driver in a drive-sleep-drive-sleep 
position that adds fatigue and diminishes ability.
    McLane supported a combination of sleeper-berth and off-duty time 
because few people sleep for 10 hours. FedEx Ground said the single 10-
hour period is rarely used; 2 and 8 and 3 and 7 are also rarely used. 
Their drivers normally split 5 and 5 or 6 and 4. FedEx stated that it 
had no evidence that the current rule has had negative effects on 
fatigue or health and did not support requiring a single 10-hour 
sleeper-berth period.
    Frequency of Sleeper-Berth Use. In the NPRM, the Agency requested 
information about how often split sleeper-berth periods are used to 
obtain the required 10 or more hours of off-duty time. Sixty-five 
commenters responded. Thirty commenters, including 7 carriers, 2 owner/
operators, and 21 drivers, said they only rarely or never used the 
split sleeper berth option. Thirty-one commenters, including 27 
drivers, said they used it often.
    Among the carriers, B.R. Williams Trucking stated that less than 10 
percent of its drivers use the exception. The reason the drivers give 
is that it is too confusing. Tennessee Commercial Warehouse discourages 
its contractors from using the exception, although about a quarter do. 
J.B. Hunt stated that a survey of randomly selected over-the-road 
driver logs showed that 14 percent of the time drivers use the 
exception. Schneider stated that only 0.4 percent of its drivers used 
the exception routinely. International Paper cited research presented 
at a Transportation Research Board conference in January 2005 
indicating that 26 percent of drivers use the exception.
    OOIDA noted that the exception is the least used feature of the 
2003 rule among respondents to its survey. About 55 percent of drivers 
reported never using it, and 75 percent of drivers used it from zero to 
four times in June 2004.
    In contrast, Maverick stated that 70 percent of its drivers use the 
exception. The Georgia Department of Motor Vehicle Safety stated that 
its inspections and observations indicate that use of the exception is 
very common.
    Health and Safety Impacts of Eliminating the Sleeper-Berth 
Exception. Four carriers, ATA, 22 drivers, and OOIDA commented on the 
health and safety impacts of eliminating the exception. Eighteen 
drivers stated that eliminating the exception would force drivers to 
drive when tired.
    Although OOIDA noted that the split sleeper berth exception is the 
least used feature of the 2003 rule, it is ``appreciated'' by those who 
use it. They include drivers who need to rest, but otherwise face 
pressure not to take short breaks that decrease their available on-duty 
and driving time. It is the only flexibility in the rule available to 
drivers who absolutely need to rest. The sleeper berth also serves 
drivers whose runs are of a certain length or whose pick-up or drop-off 
times are arranged in a way that permits a continuous two-hour break.

[[Page 50029]]

Team drivers also find the sleeper-berth exception useful.
    Yellow Roadway stated that the exception gives drivers flexibility 
to divide driving time and take breaks when needed and where they 
choose. Reducing team drivers' control of their work and rest 
opportunities could have a negative impact on driver health, safety, 
and business operations.
    Economic Impact of Eliminating Split Sleeper-Berth Exception. Five 
drivers and five carriers commented on this issue. Schneider stated 
that only six percent of teams use the exception with any regularity. 
However, elimination of this option within Schneider's teaming 
operations would impact the organization by jeopardizing $250 million 
in business opportunities with customers requesting team service.
    Werner stated customer scheduling and delivery requirements are 
such that regular hours are impossible. In addition to the limited 
availability of motels with truck parking, there is a significant cost 
to drivers staying in motels and the inconvenience factor of 
maneuvering a large truck through urban or suburban areas to locate a 
motel. If the sleeper berth exception were not available, there would 
likely be a further increase in the truck parking problem, congestion, 
and driver turnover.
    McLane stated that elimination of the exception would virtually 
eliminate use of sleeper-berth by all but cross-country long-haul 
drivers. McLane's operating costs would significantly increase, due to 
the need to hire additional drivers and equipment, while the overall 
earnings for existing drivers would be reduced.
    Quality Transport stated that eliminating the sleeper berth 
exception would largely defeat the purpose of team driving. If the 
teams cannot use the sleeper-berth rule, then they have no option but 
to show on-duty time for any time spent not driving. This would be a 
huge economic loss to companies using team operations, as it would 
basically do away with the benefit of running as a team. The loss would 
affect income for teams, plus income for the company they are leased to 
or drive for. It would affect the current national market by curbing 
deliverability of many products.
    A driver also believed that the effect of eliminating the exception 
would be to eliminate team operations. One driver said he would have to 
stop driving over-the-road. Three stated that it would affect drivers 
who use it to avoid traffic and shipper delays. One carrier simply 
stated that it would decrease efficiency.
    However, another driver saw a positive effect in eliminating an 
opportunity for shippers, carriers, and receivers to use the exception 
to pressure drivers to extend their work day. One said it would not 
change anything, but would eliminate a lot of logbook fines.
    Impact of Not Allowing a Single Sleeper-Berth Period to Extend the 
Duty Period. FMCSA asked commenters to provide information about how 
prohibiting the extension of the 14-hour tour of duty through the use 
of a single sleeper-berth period affects driver health, safe 
operations, and economic factors.
    Numerous commenters addressed this issue. Nineteen drivers, two 
carriers, a consulting group, OOIDA, and the California Highway Patrol 
responded to the question about the health and safety impacts.
    The Georgia Department of Motor Vehicle Safety described the 
problem created by the current rule. An officer who encounters a driver 
with a single sleeper period in the current tour of duty must either 
predict the driver's future actions, or question the driver, and make a 
judgment call about the driver's status.
    The California Highway Patrol addressed the negative impact of 
extending a driver's work day with only one sleeper-berth period, 
stating that it effectively circumvents the intent of the regulation 
and changes the driver's 24-hour cycle. It would allow drivers to 
operate CMVs long after the completion of the intended 14-hour work 
period. The Daecher Consulting Group also noted that allowing the 
extension would permit a slippage or rotation of the duty day.
    OOIDA described the requirement that both periods be in the sleeper 
berth, even if the driver is at home, as ``absurd.'' They stated that 
there is no justification for the requirement and are not aware of any 
study that indicates that sleeping in a sleeper berth is better than a 
bed. OOIDA recommended that the driver be able to replace the second 
period with 10 hours off. This would allow the driver the flexibility 
to restart the next day's schedule without having to relate back to the 
first sleeper period. UPS supported the OOIDA position.
    Combining Sleeper-Berth Periods With Off-Duty Periods To Calculate 
Off-Duty Time. FMCSA asked whether the rule should allow sleeper-berth 
periods to be combined with off-duty periods when calculating a 
continuous off-duty period. The Agency also asked whether a sleeper-
berth period that is part of a period of 10 or more consecutive hours 
off duty should be combinable with a later sleeper-berth period as part 
of a split sleeper-berth calculation.
    Support for combining sleeper-berth and off-duty time came from 141 
commenters, including ATA, Minnesota Trucking Association, the National 
Association of Small Trucking Companies, 41 carriers (including UPS, 
FedEx, J.B. Hunt, Con Way, and Werner) and 94 drivers. Three drivers 
were opposed.
    The California Highway Patrol recommended that a driver who 
combines a last sleeper-berth period with 10 hours off duty not be 
penalized for resting at home or be forced to sleep in the truck. 
However, if sleeper berth and off-duty time are combined, this same 
sleeper-berth period should not be used in combination with a 
subsequent sleeper-berth period. CHP recommended definitions of 
``qualifying sleeper-berth period'' and ``subsequent sleeper-berth 
period.''
    The Georgia Department of Motor Vehicle Safety stated that a full 
10-hour period of sleeper-berth time should not be combinable with a 
shorter period of time.
    ATA submitted an extensive argument in favor of amendments to the 
split sleeper-berth provisions. ATA used four hypothetical schedules to 
illustrate its argument, with three of the schedules in compliance with 
the 2003 rule, and one not in compliance. ATA claimed its hypothetical 
schedules demonstrated that, despite FMCSA's statement that drivers are 
free to take naps or other rest breaks, the rule is a strong 
disincentive to doing so if time in the sleeper berth results in lost 
work time.
    ATA also argued that the rule creates uncertainty for logbook 
inspectors. Whether an extended work period is legal or illegal depends 
on the intentions and subsequent actions of the driver, neither of 
which can be known to the enforcement officer at the time of a logbook 
check.
    Based on its analysis, ATA recommended, and provided an extensive 
discussion of the benefits of, detailed amendments to 49 CFR 
395.1(g)(1)(iii) and 395.3(a)(2) and the addition of a new exception 
specifying the following:

    A property-carrying driver is exempt from the requirements of 
Sec.  395.3(a)(2), and may extend the 14-hour limit in the event 
that the driver has one sleeper-berth period with a minimum duration 
of 2 hours, provided that the driver does not exceed 14 cumulative 
hours of work or 11 hours of driving, and that the on-duty time is 
followed by an off-duty time of at least 10 consecutive hours.

    The American Bakers Association stated the inability to combine 
off-duty

[[Page 50030]]

and sleeper-berth time ``must have been an oversight,'' arguing that it 
made no sense for operators to be tying up equipment on the lot in the 
sleeper berth when they want to go home and go to bed.
    Some carriers supported the ATA position. Others made their own 
recommendations for changes. UPS proposed permitting drivers to extend 
the 14-hour on-duty window to account for breaks of at least 2 hours 
taken in a sleeper berth when they are combined with 10 hours of off-
duty time immediately following the shift. UPS also proposed that 
drivers be permitted to extend the 14-hour on-duty window to account 
for sleeper-berth periods of at least 2 hours when they are combined 
with a subsequent sleeper-berth period of any length, if it is 
immediately followed by at least 10 hours of off-duty time. Both FedEx 
Ground and Werner recommended strongly that drivers be able to finish 
their 10 hours at home if they have a previously qualifying sleeper-
berth period. J.B. Hunt concurred and recommended that this be allowed 
for other sleeping accommodations as well. It noted that an FMCSA 
enforcement bulletin allowed this, but many jurisdictions refused to 
implement the bulletin because it directly contradicted the plain 
language of the regulation.
FMCSA Response
    Primary Sleep Period. Although the comments to the docket are 
closely divided over how to address the split sleeper berth exception, 
the majority of studies and science clearly demonstrate that drivers 
need to have at least one primary sleep period of 7 to 8 consecutive 
hours.
    A study of chronic sleep restriction [Maislin, G., et al. (2001)] 
showed that it is possible for a person to avoid physiological 
sleepiness or performance deficits on less than 7 hours of sleep; 
however, the subjects in the study were obtaining their primary sleep 
period at night and were supplementing their sleep with longer naps 
later in the day. Maislin et al. found that subjects who slept for 6.2 
hours at night combined with a nap of 1.2 hours had lower levels of 
sleepiness and higher levels of performance, compared to subjects who 
slept shorter periods without naps. While 6 hours of sleep at night 
with a nap may be the minimum needed to maintain an adequate 
performance level, it is unrealistic to think that the Agency can 
regulate what time of day a driver goes off duty or sleeps in a sleeper 
berth.
    Consequently, today's final rule modifies provisions for the use of 
sleeper berth time. The Agency will continue to allow drivers to use 
the sleeper berth to obtain their required off-duty time; however, 
drivers using this option will be required to obtain one primary sleep 
period of at least 8 consecutive hours. Unlike drivers who have to 
commute to and from work and perform personal tasks after going off 
duty, sleeper-berth drivers do not need 10 consecutive hours off duty 
in order to have an opportunity for 7-8 consecutive hours of sleep. 
Because their bedroom travels with them, sleeper-berth drivers can 
obtain adequate sleep in an 8-hour period. These drivers will also be 
required to take another separate two consecutive hours of off-duty 
time, sleeper berth time, or a combination of both. These additional 
hours will allow time for naps and other breaks, and will prevent 
drivers from operating on a 19-hour schedule (8 hours in the sleeper 
berth followed by 11 hours of driving) that would seriously compromise 
their circadian rhythm.
    For example, a driver who takes 9 consecutive hours in the sleeper 
berth would later have to take at least 2 consecutive hours of sleeper-
berth or off-duty time or a combination thereof to meet the minimum 
requirements. Since the driver did not obtain a single period of 10 
consecutive hours of off-duty or sleeper berth time, the driver is 
required to make up the balance of his or her off-duty or sleeper berth 
time later in the duty period.
    These requirements will ensure that drivers using the sleeper berth 
to obtain the minimum off-duty time have at least one primary sleep 
period of a sufficient length to provide restorative benefits. The 
second period will allow a driver to have time for a nap or rest break 
or provide an opportunity to attend to personal matters. The 
opportunity to take a nap later in the day is an important benefit, 
especially since drivers taking advantage of the sleeper berth 
provision may be operating on an irregular/rotating schedule, getting 
out of phase with their natural circadian rhythm.
    Overwhelmingly, the research literature supports the need for most 
people to obtain 7 to 8 hours of sleep per day. A study of driver 
fatigue [Wylie, C.D., et al. (1996), p. ES-10] found that the average 
amount of ``ideal'' sleep time reported by participating drivers was 
7.2 hours. The NTSB [NTSB (1996), p. 26] found that drivers in non-
fatigue related crashes had averaged 8 hours of sleep during their last 
sleep period prior to the crash versus drivers involved in fatigue-
related crashes whose prior night sleep averaged only 5.5 hours. A 
study of soldier performance [Belenky, G.L., et al. (1987), p. 1-10] 
noted that ``the vast majority of adults required 6-8 hours of sleep 
each night to maintain adequate, normal levels of daytime arousal.'' 
Belenky et al., further noted that a person getting ``six to eight 
hours sleep each night will maintain cognitive performance'' [Id., p. 
1-17].
    Research supports the benefits of sleeping at night, rather than 
during the day, but the needs of the U.S. economy and the operational 
realities of the motor carrier industry make it is impossible for FMCSA 
to ensure that drivers obtain all of their rest during nighttime hours. 
Given this, and the results of earlier studies that suggest sleep 
obtained in a sleeper berth is not as restorative as sleep obtained in 
a bed, today's rule will require drivers using the sleeper berth 
exception to obtain at least one primary sleep period of 8 consecutive 
hours in the sleeper berth. This provision maintains some of the 
flexibility provided by the 2003 rule, and ensures that drivers have 
the opportunity for 7 to 8 consecutive hours of uninterrupted sleep.
    The economic impact of this provision will be the greatest in the 
long-haul sector of the industry; however, the ``Commercial Motor 
Vehicle Driver Fatigue, Alertness, and Countermeasures Survey'' 
[Abrams, C., et al. (1997), p. 12] found that the majority of drivers 
using the split sleeper berth exception already average 6 to 7 hours in 
the sleeper berth. In addition, the 2005 FMCSA Field Survey data show 
that of the 2,928 sleeper berth periods reviewed, 68 percent exceeded 6 
hours and 52.6 percent exceeded 8 hours, so the overall impact on the 
industry should be relatively small [FMCSA Field Survey Report (2005), 
p. 2].
    Rest Breaks. The requirement for an additional 2 consecutive hours 
of off-duty or sleeper-berth time for drivers using the sleeper berth 
provides a number of additional benefits. It ensures that all drivers 
(those using a sleeper berth, and those not using a sleeper berth) will 
have the same amount of time to drive and work every week. It also 
provides the opportunity for a sleeper berth driver to eat meals, 
bathe, exercise, and conduct other personal activities. Most 
importantly, the 2 consecutive hours provide the driver with the 
opportunity to nap, if and when needed.
    Rest breaks, and especially naps, are an important tool in 
combating fatigue and the FMCSA encourages their use. As noted by Wylie 
[Wylie, D. (1998), p. 13], ``[n]aps in trips with judged

[[Page 50031]]

drowsiness appeared to result in recovery effect, compared to the 
relatively high levels of drowsiness seen in the hour prior to 
napping.'' Research on napping indicates that while it does not reduce 
accumulated fatigue, it does refresh a driver and improves performance 
in the near term. In another study of military operations [Caldwell, 
J.A., et al. (1997), pp. 2-5] the subjects performed better after 
napping compared to resting without sleep. In addition to working as a 
short-term countermeasure to fatigue experienced during working hours, 
another study [Garbarino, S., et al. (2004), p. 1300] found that 
napping ``before night work can be an effective countermeasure to 
alertness [deterioration] and performance deterioration.''
    The Agency recognizes that drivers who are able to get 7 to 8 hours 
of sleep per day may not require additional sleep and it would be 
unreasonable to require the driver to stay in the sleeper berth for an 
additional two hours. For this reason, the FMCSA will permit drivers to 
accumulate the additional two hours as sleeper berth time, off-duty 
time, or a combination of both. Two hours are long enough to permit 
time for a nap, as well as time to attend to personal matters. Studies 
have found that naps do not have to be long to improve performance. A 
study of working at night [Sallinen, M., et al. (1997), p. 25] found 
that naps of less than one hour most influenced performance, and a 
survey of train engineers found that 20 minute napping was effective 
for enhancing alertness [Moore-Ede, M., et al. (1996), p.10].
    Although this provision on the use of sleeper berths does reduce 
the total flexibility provided in the 2003 rule, it provides motor 
carriers and drivers with some operational flexibility while ensuring 
that drivers are afforded the opportunity of at least one 8-hour sleep 
period each 24 hours, with the additional benefit of providing the 
option for a nap or break.
    Enforcement. The prior split sleeper berth provision caused some 
confusion in law enforcement and the motor carrier industry. The 
question has been how to calculate split sleeper berth time, and how 
split sleeper berth periods affect the calculation of the 14-hour duty 
``window.''
    The calculation of the driver's 11-hour driving limit and 14-hour 
duty ``window'' will restart once a driver has at least 10 hours of 
off-duty time, whether it is (1) 10 consecutive hours of sleeper berth 
time; (2) 10 consecutive hours of off-duty time; or (3) a combination 
of 10 consecutive hours of sleeper berth and off-duty time. Drivers 
using sleeper berths have a fourth option to obtain the equivalent of 
10 hours off duty by combining two separate periods of sleeper berth or 
off-duty time that total at least 10 hours. When calculating off-duty 
time for drivers using sleeper berths under this rule, only two 
separate periods may be used and both must add up to at least 10 hours. 
One period must be at least 8 consecutive hours of sleeper berth time. 
The second period must be at least 2, but less than 10, consecutive 
hours of sleeper berth time, off-duty time, or a combination of both.
    For drivers using two separate periods of sleeper berth and off-
duty time, the calculation of the driver's 11-hour driving limit and 
14-hour duty ``window'' will begin from the end of the first period 
used in the calculation. This will provide a simplified method for 
calculating a driver's on-duty and driving time and address some of the 
enforcement concerns received in the comments.
    For example, following 10 consecutive hours off-duty, a driver 
begins driving at 5 a.m. At 10 a.m., the driver takes 2 consecutive 
hours off-duty (1 hour of off-duty time followed by 1 hour of sleeper 
berth time). At noon, the driver drives for another 5 hours. At 5 p.m., 
the driver goes into the sleeper berth for 8 consecutive hours. At 1 
a.m. the driver begins driving again. In this example, the calculation 
of the driver's on-duty and driving time begins at the end of the first 
off-duty/sleeper berth period, or noon. Therefore, this driver has 5 
hours of driving time available at 1 a.m. At no time will a driver have 
a combination of more than 11 hours of driving time on either side of a 
sleeper berth period or off-duty period that is less than 10 hours in 
length.
    The driver's 14-hour duty ``window'' is calculated differently from 
the way it was calculated under the 2003 rule. As identified in a 
petition filed by ATA on November 3, 2003, and numerous docket comments 
on this subject, FMCSA will not count any sleeper berth period of at 
least 8 but less than 10 consecutive hours toward the 14-hour limit 
after coming on duty. The ATA petition requested that any sleeper berth 
period of at least two consecutive hours be excluded from the 
calculation of the 14-hour duty ``window,'' provided that the driver 
took 10 consecutive hours off-duty either upon reaching his or her 14-
hour limit, or 11-hour driving limit. The Agency's response to that 
request, and the comments provided to the docket, is to allow any 
sleeper berth period of at least 8 but less than 10 consecutive hours 
to be excluded from the calculation of the 14-hour duty ``window.'' 
This will ensure that drivers using a sleeper berth to obtain their 
minimum off-duty time are not negatively impacted by having to take at 
least one sleeper berth period of at least 8 consecutive hours, which 
would normally count against their 14-hour duty ``window,'' leaving the 
driver with only 6 hours of time to work and drive. Any period of less 
than 8 consecutive hours in the sleeper berth will count toward 
calculation of the 14-hour ``driving window.''
    In the earlier example, the driver would have reached the 12th hour 
of his or her 14-hour duty ``window'' at 5 p.m. when he or she went 
into the sleeper berth for 8 consecutive hours. Because the driver has 
10 hours of off-duty time (2 hour break, combined with 8 consecutive 
hours in the sleeper berth), the calculation of the 14-hour duty 
``window'' begins at the end of the 2-hour break (noon). However, when 
the driver starts driving at 1 a.m., he or she would only be at the 5th 
hour of his or her 14-hour duty ``window,'' because the 8 consecutive 
hours in the sleeper berth are excluded from the calculation. The 
Agency believes that this will simplify the calculation used by 
enforcement officers during roadside inspections, as well as by drivers 
as they calculate their daily on-duty and driving limits.
    In the Agency's best judgment based on available data and comments, 
this sleeper berth provision creates an optimal balance by providing 
drivers with one 8-hour sleep period, combined with an additional 
sleeper berth or off-duty period, while maintaining operational 
flexibility so as not to impose an unreasonable burden on motor carrier 
productivity.

J.10. Regulation of Short-Haul Operations

    Motor carriers whose operations require the driver to return to 
their work-reporting location every night and are conducted solely 
within a 150 air-mile radius from their terminals are generally 
considered short-haul operations. Short-haul drivers perform a variety 
of non-driving tasks during the day, including receiving the day's 
schedule, loading and unloading the vehicle, making deliveries, getting 
in and out of the vehicle numerous times, lifting and carrying 
packages, and engaging in customer relations. Because of the nature of 
short-haul operations, smaller vehicles (i.e., less than 26,001 pounds) 
tend to be favored for their maneuverability, which makes them ideal 
for pick up and delivery in a local, or urban setting.

[[Page 50032]]

    A review of the U.S. Census Bureau's Vehicle Inventory and Use 
Survey (VIUS), 2002, shows that trucks weighing 26,000 pounds or less 
make up about half of all registered trucks and represent about a 
quarter of all truck miles traveled. Trucks weighing 26,000 pounds or 
less accounted for only one-seventh of all trucks involved in non-fatal 
crashes, and only one-tenth of all trucks involved in fatal crashes, 
according to data found in the Motor Carrier Management Information 
System (MCMIS) and the Fatality Analysis Reporting System (FARS). 
Relative to their share of registered trucks and annual truck miles 
traveled, trucks weighing 26,000 pounds or less are underrepresented in 
fatal and non-fatal truck-involved crashes.
    A study of the Impact of Local/Short Haul Operations on Driver 
Fatigue by Richard Hanowski and others suggested ``fatigue may not be 
the most critical issue'' in the safety of short-haul operations 
[Hanowski, R. J., et al. (1998), p. 72]. Short-haul drivers who were 
asked to describe the safety problems they faced ranked fatigue fifth, 
below problems as obscure as the design of loading docks and freeway 
on- and off-ramps. In explaining why short-haul operations did not 
produce critical levels of fatigue, the drivers said that ``unlike 
long-haul drivers, [they] typically work during daylight hours, have 
work breaks that interrupt their driving, end their shift at their home 
base, and sleep in their own beds at night'' [Id.]. Hanowski et al. 
concluded that ``[p]erhaps, when it comes to fatigue, [local/short-
haul] drivers are more like workers of non-driving professions where 
fatigue may not result from their work, as in long-haul, but may be 
impacted by their personal lives (such as not getting enough sleep at 
night)'' [Id. p. v]. While FMCSA cannot control drivers' off-duty 
behavior, the 2003 HOS rule and today's final rule give local/short-
haul drivers two more hours off duty than the regulations in effect in 
the late 1990s, when the Hanowski study was completed. If fatigue was 
not critical at that time, it is even less likely to be a significant 
threat today. Compared to long-haul drivers, local short-haul drivers 
have a better opportunity to obtain the daily restorative rest needed 
to maintain vigilance in an environment that provides quality sleep.
    Historically, the Federal Motor Carrier Safety Regulations have 
recognized differences between long-haul and short-haul operations. 
FMCSA realizes that short-haul operations are involved in crashes, and 
sometimes even fatal crashes, as evidenced by the crash data referenced 
earlier. However, the representation of short-haul vehicles weighing 
less than 26,001 pounds in large truck crashes is much lower than their 
share of the total truck population and miles traveled. The regulatory 
impact analysis (RIA) for the 2003 HOS rule bore this out, and 
researchers estimated the costs of imposing that rule on short-haul 
carriers would far exceed any safety benefits resulting from a 
reduction in fatigue-related crashes. Conversely, the net benefits of 
imposing those HOS rules on long-haul carriers were quite positive, 
primarily due to a reduction in fatigue-related crashes by long-haul 
drivers.
    Today's HOS rule adopts two exemptions for short-haul drivers also 
provided in the 2003 rule, though neither significantly improves the 
regulatory cost/benefit ratio of short-haul operations. The first is 
known as the ``100 air-mile exemption,'' and provides relief from a 
paperwork burden for drivers who meet specific duty time requirements 
(report to and leave from work within 12 consecutive hours) and operate 
in a 100 air-mile radius of their work reporting location [49 CFR 
395.1(e)]. Because drivers operating within a limited radius commonly 
make frequent stops, deliveries, and pick-ups throughout the day, which 
would normally require many entries on their records of duty status 
(RODS), this provision exempts drivers from completing RODS, as long as 
the motor carrier maintains a proper daily time record. The Interstate 
Commerce Commission adopted this provision, as a 50-mile exemption, in 
1952.
    The second exemption gives drivers the flexibility to extend the 
14-hour duty ``window'' by two hours once a week [49 CFR 395.1(o)]. The 
two extra hours can be used by the driver to meet peak demands, 
accommodate training, stage trucks for the next day's deliveries, or 
complete required recordkeeping. This final rule adopts both of these 
exemptions; however, as discussed later, the ``100 air-mile exemption'' 
is incorporated into the new regulatory regime provided for short-haul 
drivers of small CMVs in today's rule. Today's final rule makes no 
changes to the ``16-hour'' provision found at 49 CFR 395.1(o).
Comments
    In response to the discussion of short-haul operations in the 2005 
NPRM, the Agency received 18 comments addressing the need for different 
HOS rules for this class of operation. Specifically, five carriers, 
four trade associations or firms representing the construction 
industry, two other trade associations, and seven drivers recommended 
different rules for short-haul operations.
Associations
    The National Ready Mixed Concrete Association (NRMCA), the National 
Sand, Stone, and Gravel Association (NSSGA), the Colorado Ready Mixed 
Concrete Association (CRMCA), and an independent supplier of ready-
mixed concrete recommended separate rules for short-haul drivers that 
would recognize they operate under different conditions having varied 
impacts on driver safety, fatigue, and health. NRMCA stated that the 
2003 HOS rule mainly addresses the fatigue problems of long-haul 
truckers while ignoring the fact that short-haul drivers work within a 
limited radius, do not spend the majority of their time driving, begin 
and end their shifts at the same location, and sleep at home every 
night. A survey conducted by the NRMCA in 2000 indicates that drivers 
of ready-mixed concrete trucks spend, on average, only 49 percent of 
their time driving. The NRMCA, supported by the NSSGA and the CRMCA, 
recommended extending the current 100 air-mile radius to 150 miles, and 
offering drivers a 16-hour duty window, with no driving allowed after 
14 consecutive hours from the start of the duty period.
    Construction operations are mainly short-haul in nature, but other 
commenters argued that the characteristics of their particular 
industries also require special HOS rules. These other comments focused 
on drivers transporting farm products or delivering fuel to farms 
during peak seasons; drivers performing seasonal log hauling in remote 
areas; pipeline repair truck drivers; propane delivery drivers who make 
night service calls and respond to emergencies; and drivers of vehicles 
involved in environmental remediation and emergency response. The 
American Bakers Association asked that short-haul operators be allowed 
to retain the once-a-week 16-hour duty-period. Two contractors to the 
U.S. Postal Service opposed the current 14-hour provision, arguing that 
unless split-shift time spent at home or in a designated sleeping area 
qualifies the same as a sleeper-berth, the rule will hurt small 
companies. These companies would then have to hire more drivers to 
accommodate the additional off-duty time required, which in turn would 
put more inexperienced drivers on the road.
    The U.S. Chamber of Commerce stated that the FMCSA's 2003 RIA 
demonstrated that short-haul operators were not expected to see any 
benefits from the rule adopted that year, which

[[Page 50033]]

supports the need for separate handling of short-haul and long-haul 
operations. The Chamber argued that short-haul operations should not be 
subject to a rule that fails to produce a net benefit for those 
operations.
Carriers
    United Parcel Service (UPS) cited research showing that fatigue 
effects are less likely in short-haul drivers because they work 
daylight hours, have work breaks, begin and end at their home location, 
and sleep in their own bed at night. The research also found that 
drivers who work in short-haul operations have varied task 
responsibilities compared to the monotonous task of driving long-haul 
routes, and this is also a factor in the lower level of fatigue.
    UPS noted that if short-haul driving is not a substantial cause of 
fatigue, strict HOS regulations are less likely to have beneficial 
safety effects. UPS concluded that the HOS rule should be modified to 
recognize the differences between long-haul and short-haul operations. 
UPS proposed that FMCSA permit an individual who drives less than 25 
hours per week and 5.5 hours per day, and whose driving is primarily 
local, to extend the 14-hour duty-period by the amount of time taken in 
breaks and other off-duty time, and to combine split periods of off-
duty time for the purpose of acquiring the ten hours of off-duty time 
necessary to return to duty. UPS also proposed that the 100 air-mile 
radius rule allow a driver to return to his or her work reporting 
location within 14 consecutive hours, instead of the 12 hours currently 
specified.
    Other trucking companies also expressed concern with the short-haul 
provisions. One small carrier urged FMCSA to retain the exemption that 
allows an additional 2 hours of duty time once per week. Another 
supported the exemption and suggested a traditional time clock formula 
for tracing duty time by requiring the drivers to ``punch in and out.''
FMCSA Response
    The research and data reviewed by the Agency demonstrate that 
fatigue has relatively little impact on short-haul trucking. The 
comments also strongly support that conclusion. Because the benefits of 
HOS regulations for those operations are quite disproportionate to 
their costs, FMCSA has decided to create a new regulatory regime for a 
more specific subset of short-haul operations.
    Under the rule adopted today, drivers of CMVs that do not require a 
CDL to operate will be allowed to extend their 14-hour duty ``window'' 
by 2 hours twice per week, but the driver must: (1) Have 10 consecutive 
hours off-duty prior to the start of the workday; (2) not drive after 
the 14th consecutive hour since coming on-duty on the days he or she 
does not use the 2 additional hours provided by this provision; (3) not 
drive more than 11 hours after coming on duty; (4) not drive after 
having been on duty for 60 hours in a 7-day period, or 70 hours in an 
8-day period, including the 34-hour recovery provision; (5) not operate 
beyond a 150 air-mile radius from the location where he or she reports 
to, and is released from, work; and (6) return to his or her work 
reporting location at the end of each work day. In addition, these 
drivers will not have to keep records of duty status. However, the 
employing motor carrier must maintain a time record for six months 
showing the time the driver reports to, and is released from work, 
consistent with the time keeping requirements under the current 100 
air-mile radius exemption. To simplify compliance with this new short-
haul HOS provision, drivers to whom it applies will not be able to use 
the sleeper berth exception or the current 100 air-mile radius short-
haul exemption.
    Short-haul drivers are unique to the motor carrier industry in that 
they do not drive for long periods of time. The nature of short-haul 
operations (repeated pickups and deliveries) and vehicles (too small 
for operations that require long driving stints) make driving long 
hours logistically and economically unfeasible and unnecessary. 
Hanowski [Hanowski, R.J., et. al (1998), p.5] found that only 50 
percent of a short-haul driver's time is actually spent driving, and 
that time was scattered throughout the day. However, these operations 
do experience occasional extended days during peak times of the year 
where the necessity to extend their work day by 2 hours is needed.
    Due to the variety of tasks short-haul drivers conduct throughout 
the day, traditional ``time-on-task'' models do not apply. However, 
through the Agency's literature search both laboratory and field 
research studies were found that support the ability to work a 16-hour 
shift without significant degradation of performance. A laboratory 
study of sleep restriction and sleep deprivation found the critical 
limit to wakefulness when performance begins to lapse was statistically 
estimated to be about 16 hours [Van Dongen, H.P.A, et al. (2003), p. 
123]. In a study of drivers in New Zealand, researchers found that 
drivers could maintain their performance until about the 17th hour of 
wakefulness, after which performance capacity was sufficiently impaired 
to be a safety concern [Williamson, A.M., et al. (2000), p. 19].
    While the short-haul industry can experience long work days during 
peak times of the year, it is the Agency's best judgment that longer 
workdays will not translate into longer driving times in the short-haul 
environment where there is relatively little driving, but rather 
several other job-related activities. As noted earlier, short-haul 
drivers rarely, if ever, accumulate 11 hours of driving, regardless of 
the workday length. FMCSA concludes that the rhythm of local operations 
will limit the use of this new provision in any case, but the Agency 
wants to give this segment of the motor carrier industry as much 
flexibility as possible to structure their operations efficiently, 
while still providing a safety regime to address deficiencies.
    The research is limited on issues related to the health of short-
haul drivers. However, one study specifically addressed driver health 
issues and short-haul drivers. This study identified the occupational 
stress that short-haul drivers encounter on a daily basis. Orris et al. 
administered a questionnaire to 317 short-haul drivers who worked out 
of distribution centers in New Jersey, Wisconsin, Texas, and California 
[Orris, P., et al. (1997)]. Each participant was given a packet that 
included six self-administered questionnaires related to occupational 
stress. The results indicated that short-haul drivers had a significant 
elevation of stress-related symptoms over the general adult population. 
Further analyses indicated that one reason for the stress was that 
drivers believed that their workload was unreasonable, and that they 
were faced with rigid deadlines.
    Another study [Hanowski, R. J., et al. (1998)] conducted focus 
groups with 82 experienced short-haul drivers to identify safety 
problems in the short-haul industry. The two top concerns most often 
mentioned by short-haul drivers were the problems caused by drivers of 
light non-commercial vehicles and stress due to time pressure [Id., p. 
70]. As identified in the comments to the docket, occupational stress 
due to rigid time pressure and not having enough time in the day to get 
the job done was mentioned as a safety problem.
    The short-haul provision in this final rule does not increase the 
maximum permissible weekly work hours (the 60 and 70-hour rules are 
still applicable to short-haul drivers) or daily driving time (the 11-
hour driving limit per day)

[[Page 50034]]

allowed in today's final rule. However, the provision does provide 
short-haul operations greater flexibility in scheduling, especially 
during periods of peak demand. For 2 days per week, short-haul drivers 
will be allowed 2 additional hours during which they can drive, 
although their total maximum daily driving time remains the same. The 
Agency believes this will reduce the occupational stress short-haul 
drivers feel when trying to make too many deliveries in a limited time. 
FMCSA has concluded that this short-haul provision will not adversely 
affect the health of short-haul drivers.
    Short-haul drivers do experience fatigue, however, and in a field 
study it was found that these drivers take 1-to 2-hour naps to reduce 
any fatigue accrued during the course of a normal work day. The study 
showed that these naps are taken while drivers wait for their vehicle 
to be loaded or unloaded or during normal meal breaks [Balkin, T., et 
al. (2000), p. 4-63]. These naps are in addition to the routine breaks 
these drivers utilize through the course of their day. FMCSA has 
concluded that the unique characteristics of their operations enable 
short-haul drivers to maintain the alertness and vigilance needed to 
drive up to the 16th hour after coming on duty twice a week, a 
conclusion supported by the fact that short-haul drivers are involved 
in fewer crashes per vehicle miles traveled than long-haul drivers.
    Vehicles that require the driver to have a CDL are defined as any 
``motor vehicle or combination of motor vehicles used in commerce to 
transport passengers or property if the motor vehicle (a) Has a gross 
combination weight rating of 11,794 kilograms or more (26,001 pounds or 
more) inclusive of a towed unit(s) with a gross vehicle weight rating 
of more than 4,536 kilograms (10,000 pounds); or (b) Has a gross 
vehicle weight rating of 11,794 or more kilograms (26,001 pounds or 
more); or (c) Is designed to transport 16 or more passengers, including 
the driver; or (d) Is of any size and is used in the transportation of 
hazardous materials as defined in this section'' [49 CFR 383.5]. 
Drivers of vehicles transporting placardable quantities of hazardous 
materials will not be able to use this new rule because they are 
required to have a CDL, regardless of the weight of the vehicle. 
However, the new regulatory regime is applicable to drivers who possess 
a CDL, but drive a vehicle that does not require a CDL to operate.
    By limiting the applicability of this short-haul rule to operators 
of vehicles not requiring a CDL, the Agency is using a recognized and 
logical break point. Vehicles with a weight of less than 26,001 pounds 
have long been acknowledged by law enforcement, the International 
Registration Plan (IRP) requirements, truck manufacturers, and Congress 
as a distinct vehicle class. In most cases, the size of a vehicle 
determines the class of driver's license needed to operate it. Only 
when a vehicle carries a placardable amount of hazardous materials do 
the size and weight of the vehicle not make a difference. The IRP is a 
commercial vehicle registration system entered into by the individual 
states of the United States (excluding Alaska and Hawaii), the District 
of Columbia, and various provinces of Canada that allows one IRP member 
to process commercial vehicle registrations and collect fees for other 
members. The IRP uses 26,000 pounds as its weight threshold, 
demonstrating that States consider this weight a non-arbitrary divide 
between vehicles likely to be operated in interstate commerce over long 
distances and those that operate locally. The IRP ``apportioned'' 
license plate will also help alert law enforcement officers to vehicles 
that are most probably over 26,000 pounds, thus identifying drivers not 
eligible for this new regulatory regime. In addition, regardless of 
license plate, law enforcement officers are trained under 49 CFR 383.91 
to recognize vehicles under 26,001 pounds by their appearance. The 
classification system used by truck manufacturers and the National 
Highway Traffic Safety Administration has long specified 26,000 pounds 
as the upper limit for a Class 6 truck [49 CFR 565.5, Table III]. 
Congress itself recognized the limited operational role of lighter 
vehicles by requiring a CDL only for drivers of Class 7 and 8 trucks 
starting at 26,001 pounds GVWR (and certain passenger and hazmat 
vehicles).
    Groups such as the NRMCA, NSSGA, and the CRMCA represent short-haul 
motor carriers, but virtually all of their operations involve CMVs that 
weigh more than 26,000 pounds. FMCSA has decided not to extend the new 
regime to all short-haul carriers, but only those using smaller (i.e. 
under 26,001 lbs) vehicles. Many short-haul operators use van or tank 
trailers indistinguishable from those employed in long-haul trucking, 
for example, to re-supply supermarkets or gas stations. While ready-
mixed concrete trucks are not used in long-haul operations, they do 
require a CDL to operate. Vehicles that require a CDL are likely to be 
driven more than smaller vehicles that do not, simply because their 
capacity makes them ideal for transporting large loads point-to-point, 
but not for local delivery. The combination of more driving time and 
greater mass makes these vehicles potentially more dangerous than 
smaller trucks. FMCSA has therefore concluded that the new HOS regime 
should be limited to operators of lighter truck (i.e., those not 
requiring the driver to hold a CDL).
    When reviewing the activities of CMV drivers, the Agency found that 
drivers of light vehicles spend less time driving and more time 
completing other non-driving tasks, such as those referenced earlier. 
The economics of this concept are fairly straightforward: The greater 
the cargo capacity of the vehicle, the greater the benefit of operating 
it longer distances and for longer hours. Conversely, the less cargo 
capacity, the less economic sense it makes to operate the vehicle over 
longer distances, or for longer hours. Thus, drivers in operations that 
use lighter vehicles are less likely to spend time driving. 
Operationally, the lighter vehicles tend to be smaller and more 
maneuverable, making them ideal for local pick up and delivery 
operations in localized settings. The drivers spend most of their time 
in and out of the vehicle, serving their customers and doing ancillary 
duties, such as stocking shelves and checking inventories.
    This analysis is supported by data in the U.S. Census Bureau's 2002 
Vehicle Inventory and Use Survey (VIUS) which shows that about 90 
percent of all trucks weighing 26,000 pounds or less operate within a 
150-mile radius. VIUS also shows that trucks with a GVWR of less than 
26,001 pounds with a primary range of operation within 150 miles 
comprise about 46 percent of all trucks operated in the United States. 
Only a small portion of these vehicles require the driver to possess a 
CDL.
    Trucks Involved in Fatal Accidents (TIFA) data from the years 1994 
to 2002 (excluding 2001) show that about 12.7 percent of all CMVs 
involved in fatigue-related crashes weighed less than 26,001 pounds. 
Additionally, TIFA data indicate that CMVs weighing less than 26,001 
pounds and engaged in trips of 150 miles or less account for only 6.8 
percent of all large trucks involved in fatigue-related fatal crashes 
between 1994 and 2002. Conversely, these vehicles represent 52 percent 
of all large trucks registered in 2002, according to the U.S. Census 
Bureau's Vehicle Inventory and Use Survey.
    A study of Short-Haul Trucks and Driver Fatigue by Dawn Massie and 
her colleagues found that short-haul trucks (which they defined as 
Class 3-6 straight trucks, i.e. 10,001 to 26,001

[[Page 50035]]

pounds) have a very low fatal-involvement rate compared to other trucks 
[Massie, D.L., et al. (1997), pp. 20-21]. As FMCSA pointed out in the 
2000 HOS NRPM, the Massie study concluded that ``[l]ocal single-unit 
straight trucks had an average of 0.0022 fatigue-related fatal 
involvements per 1,000 registered trucks. The comparable figure for 
long-haul tractor-trailers was 0.0781, approximately 35 times higher. 
On a per-mile basis, long-haul trucks were almost 20 times more likely 
to be involved in a fatigue-related crash.'' [65 FR 25540, at 25546].
    There are some possible reasons for these lower fatigue-related 
crash rates. Drivers in short-haul and local operations spend 
relatively little time actually driving the vehicle. The drivers in the 
study by Hanowski [Hanowski, R.J., et al. (2000), p. 77] reported an 
average shift time of 10.89 hours but only averaged 92 miles of driving 
per shift. The drivers primarily worked 5 days per week. In fact, of 
the 462 shifts examined by Hanowski, there were only two instances 
where a driver worked on a Saturday and both of those shifts were less 
than 8 hours long. Hanowski found that about 61 percent of drivers' 
time was spent completing tasks other than driving--35 percent on 
loading/unloading and 26 percent on other assignments (vehicle 
inspections, merchandising, etc.).
    In addition to reduced driving time, reports suggest that light to 
moderate physical activity during the workday lessens a driver's 
physiological fatigue. For example, Mackie and Miller stated that 
``light work stress did not lead to any cumulative fatigue'' and there 
were ``[n]o significant differences in subjective fatigue between 
drivers who engaged in light versus moderate cargo loading'' [Mackie, 
R.R., & Miller, J.C. (1978), p. X]. Hanowski found that drivers 
classified as not fatigued spent over an hour more time loading and 
unloading the vehicle. The explanation, he and his colleagues 
concluded, ``is that the physical loading/unloading helps drivers avoid 
fatigue'' [Hanowski, R.J., et al. (2000), p.112].
    For all of these reasons, in the Agency's best judgment, a new HOS 
regime for a specific subset of short-haul operations is warranted. 
However, FMCSA will closely monitor fatigue data, particularly fatigue-
related crash data for this group of carrier operations, and will look 
at further fatigue-related research on short-haul operations.

J.11. Combined Effects

    Commenters provided a variety of responses to the Agency's NPRM 
request to provide studies or other data on the ``combined or net 
effects'' of the various regulatory provisions in the 2003 rule on 
driver health, the safe operation of CMVs, and economic factors. The 
Agency also asked about ``mutual interactions'' of the various 
provisions. Consequently, commenters discussed the combined effects and 
interactions of the provisions on health and safety. In addition, they 
discussed both how health and safety are related to each other 
separately and when considered with various provisions. Combined 
effects for purposes of this discussion are distinguished as follows: 
(1) A cumulative effect refers to the net impacts of various 
provisions; and (2) interactions refer to how changes to one or more 
provisions impact one or more other provisions.
Comments
    Paradigm Shift Needed? Circadian Technologies stated that the 
complexity of the issues requires consideration of a new, flexible 
paradigm. A summary of their comments follows: The 2003 rule focuses on 
effects of the number of hours allocated to the existing provisions 
after beginning a work week, but does not acknowledge that alertness, 
safe performance, and health of a driver depend far more on how sleep-
deprived a driver is than how many hours he or she has been on duty or 
driving. Continuous wakefulness (which can be longer than duty-tour 
time), sleep length and quality, and sleep obtained over the prior week 
are highly relevant to fatigue. According to Circadian Technologies, 
the 2003 rule may unintentionally require drivers to rest when sleep is 
difficult to obtain, compress their sleep when it is most needed, and 
discourage them from interrupting their duty time to take brief naps. 
This may result in high levels of chronic and acute sleep deprivation. 
The complex interaction between sleep science and trucking operations 
defies a one-size-fits-all rule that is understandable by drivers and 
enforceable by regulators.
FMCSA Response
    In drafting this final rule, the Agency balanced the potential 
safety and health impacts, and costs, while considering compliance and 
enforcement issues. In the 2000 NPRM, FMCSA attempted to tailor the 
rule to specific industry sectors and their unique operating 
environments to avoid a blanket approach. This tailored approach, 
however, was firmly rejected by a substantial majority of industry as 
unduly complex. Circadian Technologies was the sole commenter 
suggesting a paradigm shift was needed, and neither the public interest 
advocates nor industry supported replacing the 2003 provisions with a 
new paradigm in the 2005 rule. A significant body of research supports 
retaining the major provisions of the rule, modified by the changes 
discussed earlier.
Comments
    Health. Different perspectives were provided by commenters 
regarding the health risks of the 2003 rule, though all were described 
as cumulative, versus interactive. ATA stated that potential driver 
exposure to diesel exhaust emissions have decreased substantially over 
the last several years and such decreases will likely continue. In 
addition, these potential DE hazards are now within levels established 
by EPA and OSHA. ATA also stated that the 2003 rule provides a 
sufficient sleep opportunity to mitigate the potentially adverse health 
outcomes from sleep debt.
    Others disagreed with this assessment, based on substantive and 
procedural issues. Regarding their substantive concerns, Public Citizen 
requested that FMCSA address diesel emission-related health risks by 
significantly decreasing both daily and weekly driving hours. NIOSH 
commented that there are potential long-term health effects associated 
with repeated periods of extended duty, especially given that the 2003 
regulations permit up to 84 duty hours per 7 days, or double the duty 
hours of the average U.S. worker. They also noted that long-term 
exposure to extended work hours and driving in particular may have 
health consequences, including raised risks of myocardial infarction 
and back injury. Alertness Solutions agreed that driver health factors 
related to fatigue, such as total and partial sleep loss, extended 
wakefulness, and circadian disruption, have been associated with 
degraded physiological and health outcomes. However, Alertness 
Solutions pointed out that the studies generally have shown that total 
sleep loss or sleep restriction to 4 hours for 6 consecutive nights is 
required to trigger these associations.
    Of the several points AHAS made on health impacts, two are 
summarized as follows: first, the rule does not address the health 
impact of potentially increasing duty tours by 40 percent and driving 
hours by 30 percent, or allowing drivers to alternate between 11 hours 
of driving and 10 hours of off-duty time; and second, sleep debt from 
long or irregular shifts is strongly associated with major changes in 
metabolic and endocrine function.

[[Page 50036]]

    AHAS maintained that there was not an independent review of health 
effects by FMCSA prior to issuing the 2003 rule. Also, they stated that 
the Agency cited but failed to apply health study findings previously 
cited in its 2000 NPRM and 2003 final rule.
FMCSA Response
    It appears that chronic exposure to DE may cause cancer. The 
exposure/dose required, however, is currently unknown, due to the 
extreme difficulty in measuring and modeling exposure. For instance, 
EPA has noted that there is great ``uncertainty regarding whether the 
health hazards identified from previous studies using emissions from 
older engines can be applied to present-day environmental emissions and 
related exposures, as some physical and chemical characteristics of the 
emissions from certain sources have changed over time. Available data 
are not sufficient to provide definitive answers to this question 
because changes in DE composition over time cannot be confidently 
quantified, and the relationship between the DE components and the 
mode(s) of action for DE toxicity is unclear'' [Ris, C. (2003), p. 35]. 
EPA's combined actions of tightening the standards for DE and fuel 
standards lead to a projection of dramatically lower DE through 2030. 
Based on these projections, the health effects linked to DE should be 
reduced over time.
    The Agency has two responses regarding the health impacts of longer 
hours permissible under the new regulations. First, based on research 
conducted by FMCSA, including literature reviews performed by the 
National Academies (see process discussion in next paragraph), there is 
a lack of knowledge on, and great deal of uncertainty about, whether 
the potential long hours alone adversely affect driver health. Second, 
even if there is a potential for impacts from longer hours for drivers, 
despite the uncertainties of detection and modeling described above, 
based on FMCSA's driver survey, data from Campbell and Belzer (2000), 
and data submitted by carriers, including Schneider National and FedEx, 
there is no evidence that drivers have drastically increased their 
hours of driving or work. Therefore, there is no evidence drivers will 
be subject to deleterious health effects [under 49 U.S.C. 31136(a)(4)] 
resulting from their exposure to DE based on changes to the rule 
published today. In conclusion, regarding DE exposure and health 
impacts, FMCSA believes that while DE probably entails some risk to 
drivers, today's HOS rule neither causes nor exacerbates that risk, 
compared to the pre-2003 rule.
    From a process perspective, in preparing the final rule FMCSA 
extensively researched both health and fatigue studies through 
consultation with an inter-agency group of Federal safety and health 
experts. First, the Agency reviewed numerous studies, which included 
those findings previously cited in its 2000 NPRM and 2003 final rule. 
Second, as discussed in detail in section D, we tasked nationally known 
health and fatigue experts associated with the National Academies' 
Transportation Research Board (TRB) with conducting a thorough 
literature review of studies relevant to this rulemaking. Specifically, 
this review included research findings that discussed in a scientific, 
experimental, qualitative, and quantitative way the relationship 
between the hours a person works and drives, the structure of the work 
schedule (on-duty/off-duty cycles, time-on-task, especially time in 
continuous driving, sleep time, etc.), and the impact on the health and 
fatigue of a commercial motor vehicle driver.
    As a result of the questions raised in the NPRM, commenters cited 
over 200 studies to the HOS docket concerning health and fatigue. Of 
these, the TRB team utilized the screening criteria from the original 
research stage and selected key studies to review and summarize for 
this health and safety evaluation.
Comments
    Fatigue: Cumulative effects. Several commenters raised concerns 
about the perceived negative cumulative effects of the 2003 rule. Also, 
based on interviews of long distance drivers in two States, the 
Insurance Institute for Highway Safety (IIHS) found that drivers are 
driving more hours and that fatigued driving is at least as common as 
it was previously. IIHS, Public Citizen, and AHAS voiced concern about 
the potential for increased fatigue based on the increase in driving of 
both daily and weekly hours. IIHS also emphasized that the impact is 
due to the fact that up to 42 percent of drivers in one interview said 
they drove 10 or more hours a day and used the recovery provision. AHAS 
criticized Alertness Solutions' paper submitted to the docket as an 
attempt to cast doubt on relevant studies while ignoring a significant 
amount of key literature supplied both by AHAS and FMCSA showing that 
the rule's provisions in combination lead to increased fatigue, lower 
performance, and a higher risk of crashes. AHAS further asserted that 
while Rosekind of Alertness Solutions agrees with FMCSA in his earlier 
literature that two successive nights of sleep are needed for recovery, 
he contradicts this in his comment submitted to the docket via 
Alertness Solutions by arguing that two 8-hour periods are adequate.
    On the other hand, numerous carriers raised the point that over the 
2003-2004 year crash frequency declined, resulting in a marked safety 
improvement. The National Private Truck Council (NPTC) was one of many 
industry representatives which acknowledged that, while it is hard to 
definitively link these safety improvements to the hours-of-service 
rules, the rule was in many cases the ``only variable'' that changed 
over that year. This data, according to these commenters, refutes 
arguments made by others about the negative impact of the 2003 rule. 
Several commenters, such as FedEx Ground, noted that such safety 
improvements were notable in light of an overall increase in vehicle 
miles traveled. The Motor Freight Carriers Association stated that the 
cumulative effect of the various provisions resulted in positive safety 
benefits. The National Industrial Transportation League (NITL) stated 
that the provisions in the 2003 rule combined to significantly 
ameliorate chronic fatigue. The American Moving and Storage Association 
(AMSA) cited data they collected to support the safety benefits of the 
new rule, which stem from a more natural circadian routine and 
additional rest time.
    Fatigue: Interactions/Offset. Several commenters raised concerns 
about how the various provisions interacted or offset each other. Some 
disagreed with how the various provisions were allocated quantitatively 
(e.g., hours of driving time) and argued that their interaction 
resulted in reduced safety. For instance, AHAS stated that even 
assuming the benefits of increasing off-duty time by two hours under 
the 2003 rule, the dramatic increase in weekly driving hours permitted 
by the 34-hour recovery period ensures that drivers will be more, not 
less fatigued and be more exposed to risk. Similarly, Public Citizen 
noted that even assuming positive benefits of the decreased tour of 
duty provision under the 2003 rule, the increased driving allowed may 
negatively offset such benefits. They also said that crash risk may 
increase as a result. The AFL-CIO maintains that the cumulative 
fatiguing effects of an extra hour of driving each day and the 34-hour 
recovery provision negate the positive aspects of establishing a 24-
hour clock.
    Many commenters supported the safety benefits resulting from the 
interactions of the provisions. For example, ATA supported the Agency's

[[Page 50037]]

conclusion that it could permit a 1-hour increase in driving time from 
10 to 11 hours because it had mandated an overall reduced tour of duty. 
Also, while the length of duty tour needs to be limited based on 
research concerning continuous wakefulness, little is known about the 
impacts of driving time. According to C.R. England, the interaction of 
the current provisions provides good balance by allowing additional 
driving time (11 hours) with more rest opportunity (10 hours) and a 34-
hour recovery period to recover from any cumulative fatigue that may 
occur. They also pointed out that the 10-hour off-duty provision 
eliminates daily fatigue while the two 8-hour sleep periods in the 34-
hour recovery provision provide an adequate opportunity for full 
recovery. Schneider National Inc. agreed that the 10-hour off-duty 
provision eliminates daily fatigue, while the 34-hour recovery 
provision eliminates cumulative fatigue on a weekly basis. They also 
noted that the 10-hour off-duty period supports both the 11 hours of 
driving and 34-hour recovery provisions. Fresenius Medical Care stated 
that under the 2003 rules, the driver usually has adequate time to 
commute and attend to personal matters, while still obtaining 8 
consecutive hours of sleep. FedEx Freight argued, regarding the 11th 
(added) hour of driving provided by the 2003 rule, that 
``statistically'' no crashes happened after the 10th hour of driving; 
therefore, no offsetting adjustments in other provisions are needed. 
Based on International Paper's experience with the rule, the majority 
of drivers do not have the opportunity to drive a full 11 hours, given 
the impact of the maximum ``on-duty'' of 14 hours, and any reversal of 
this would not achieve the desired increase in safety.
    Fatigue: 24-hour Cycle. The interactions resulting in a movement 
towards a 24-hour clock were characterized by commenters as beneficial, 
though some concerns were raised. The two main issues were: First, the 
composition of the 24-hour cycle through the combination of the 10-hour 
off-duty period with the 14-hour driving window; and, second, the 
impact of backward rotating schedules. First, according to ATA, the 14 
consecutive hour on-duty limit, coupled with 10-hours off-duty 
requirement, is a synergistic safety feature of the new rule resulting 
in a consistent 24-hour work-rest cycle. Tennessee Commercial Warehouse 
noted that for long-haul drivers, the 14 consecutive hour shift, 
coupled with the 11 hours of driving, has allowed them to maintain 
their income level and establish a 24-hour cycle; consequently, drivers 
take their off-duty break about the same time every day. Second, 
according to Circadian Technologies, by extending both the number of 
hours of off-duty time required per day (from 8 to 10), and the number 
of hours of driving allowed (from 10 to 11), the new rule extends the 
minimum day-night cycle from 18 hours to 21 hours, assuming drivers 
drive the maximum allowable (and have no on-duty not-driving time). 
This reduces the likelihood of drivers falling into backward rotating 
schedules that can impact health and fatigue. While such schedules are 
still permissible under the rule being adopted today, the added off-
duty hours help reduce the severity of the rotation. ATA's comment on 
this topic typified other associations, suggesting that even if a 
driver maximizes driving time with little additional duty time and 
takes the minimum 10 hours off-duty, this 21-22 hour cycle comes closer 
to a 24-hour circadian cycle than the 18-to 19-hour cycle possible 
under the pre-2003 rule.
    Among those raising concerns about the 24-hour cycle, Circadian 
Technologies maintained that a 24-hour clock does not help a driver 
whose first off-duty period starts during a time of day when it is 
difficult from a circadian standpoint to sleep. Public Citizen noted 
that, based on FHWA's 1996 study, the strongest and most consistent 
factor influencing driver fatigue and alertness was time of day; 
drowsiness was markedly greater during night driving than during 
daytime driving. They also noted that while the Agency has suggested 
that the 14-hour duty tour/10-hour off-duty provisions combine to 
establish a 24-hour schedule, the one hour reduction in duty tour is 
not relevant to the number of driving hours because drivers will 
utilize the maximum driving hours to enhance their wages and meet 
deadlines. On the other hand, drivers will tend to minimize clocking 
on-duty hours, because they do not typically get paid on that basis. To 
address these perceived shortcomings, Public Citizen suggested that 
drivers on long shifts be required to use the remaining on-duty hours 
available after they finish driving or add on the remaining hours to 
their off-duty period. This would ensure that drivers remain on a true 
24-hour schedule.
    Fatigue: Breaks. According to ATA, the benefit of having a work 
limit within a duty period is that it creates other time within which 
breaks can be taken; such breaks can have a beneficial effect on 
fatigue. Other commenters, including Circadian Technologies and several 
drivers, argued that, despite the positive benefits of attempting to 
achieve a 24-hour cycle, the 14-hour on-duty cycle has the negative 
effect of discouraging rest breaks, which may include beneficial naps.
    Fatigue: Quality of Life Impacts. FMCSA asked whether drivers were 
obtaining more rest under the 2003 rule and whether the quality of 
their lives had improved. The results are shown below in Figure 10.

                        Figure 10.--Comments on Rest and Quality of Life Under 2003 Rule
----------------------------------------------------------------------------------------------------------------
                                                                Carriers           Drivers           Other*
----------------------------------------------------------------------------------------------------------------
More Rest:
    Yes...................................................                29               114                 5
    No....................................................                 4                46                 2
Quality of life:
    Better................................................                18                70                 2
    No Change.............................................                 1                16                 1
    Worse.................................................                 3                34                1
----------------------------------------------------------------------------------------------------------------
* Includes comments from trucking associations.

    Commenters mentioned that the rule's off-duty time provided the 
opportunity not only for sleep, but also for relaxation and personal 
tasks. Of the drivers and owner-operators who stated that they do not 
get more rest, some criticized the 14-consecutive-hour provision 
because naps and rest periods do not stop the duty-tour ``clock.'' 
Drivers also thought that off-duty/sleeper-berth time was too long, and 
waiting for the time to end was very tiring. Other drivers said that

[[Page 50038]]

the rule caused them to waste more time and to drive in worse 
conditions.
    The commenters who said the quality of their lives had improved 
under the rule credited the reduced or regulated workday that allowed 
them to have more time at home and for leisure activities. They also 
mentioned an improved relationship with carriers, shippers, and 
receivers because the companies recognize that the rule limits the time 
a driver can be on duty. Those who reported no change or a worse 
quality of life cited the 14-hour rule and the requirement for a 10-
hour off-duty period when away from home.
    Two commenters thought their quality of life was better in some 
ways and worse in others because of the rule. One commenter noted that 
there was confusion about the rule's provisions, e.g., some drivers 
think they are required to sleep for 10 hours. Two carriers had 
surveyed their drivers. Landstar Systems found that 73 percent of the 
drivers thought their personal lives had not changed and 44 percent 
said they were home less often under the rule. J.B. Hunt found that 38 
percent of the drivers saw no effect on their personal lives and only 
15.8 percent thought their personal lives had improved under the rule.
    Fatigue: Regulatory Impact Analysis. Public Citizen noted that 
FMCSA failed to demonstrate how the extra off-duty time enhances a 
driver's ability to drive an additional hour. Public Citizen also 
stated that while the Agency claimed the rule produced substantial net 
safety benefits, the RIA did not take time-on-task into account. In 
addition, the notion that time-on-task effects are zero is implausible. 
If driver fatigue rises with additional consecutive driving hours and 
drivers are fatigued after 8 hours, they will be more tired after 11 
compared to 9 or 10 hours; if they are fatigued after working 60-70 
hours in 7 or 8 days, they will be even more so after working 84-98 
hours in the same periods.
FMCSA Response
    Cumulative Effects, Interactions/offsets, Breaks, Quality of Life, 
and RIA. The Agency requested and received comments about both 
cumulative and interaction impacts on fatigue, has collected new data, 
and has thoroughly reviewed the scientific evidence. FMCSA's best 
judgment is that the rule finalized today provides the best possible 
regulation considering both the cumulative and interaction impacts on 
fatigue. Our response to both types of effects are discussed together 
later in this section.
    Today's rule can be summarized in six points: (1) Adopts 11 hours 
of daily driving time as the maximum allowed following a 10-hour off-
duty period; (2) adopts a 14-hour duty tour ``driving window;'' (3) 
eliminates the split sleeper berth exception traditionally allowed by 
requiring 8 hours of consecutive anchor sleep and an additional two 
hours of off-duty or sleeper-berth time; (4) requires a 10-hour off-
duty period; (5) allows a 34-hour recovery provision; and (6) provides 
that short-haul drivers of vehicles not requiring a CDL who operate 
within a 150-mile radius of their normal work reporting location may 
drive 11 hours within a 16-hour work shift 2 days in any period of 7 
consecutive days, while, among other provisions (further described in 
Section J.10 on short-haul operations) requiring compliance with the 
same provisions applicable to other drivers (described in this 
paragraph above) for the other 5 days.
    The Agency's seven fatigue-related rationales for the rule being 
adopted today, based on extensive research into these provisions and 
how they are related, follow.
    First, compared to pre-2003, the Agency is adopting a shorter and 
stricter duty tour ``window'' to prevent drivers from drastically 
extending their day through the use of breaks. Adopting this provision 
is justified because continuous daily wakefulness is among the 
strongest predictors of fatigue, and the Agency's best judgment 
indicates it outweighs driving time as a predictor of fatigue. 
Therefore, FMCSA is requiring this provision to reduce driver fatigue 
by ensuring that the provision extending the work day is eliminated.
    Second, the Agency modified the 2003 sleeper berth provision to 
ensure all drivers have the daily opportunity to obtain 8 hours of 
consecutive rest and a total of 10 hours off-duty. Specifically, the 
split sleeper berth provision has been eliminated and each driver using 
a sleeper berth must obtain a primary period of 8 consecutive hours of 
off-duty time in the berth. Such drivers must also take an additional 
2-hour off-duty period that is in or outside of the sleeper berth, 
either consecutively with, or separately from, the primary 8-hour 
period. The 10-hour off-duty period will enable drivers to combat daily 
fatigue, provide opportunities to attend to personal matters, and 
obtain rest, including naps. The ability for the driver to take a nap 
later in the day is an important benefit, especially considering that 
drivers taking advantage of the sleeper berth exception could be on a 
rotating schedule, or off a natural circadian rhythm.
    Third, the Agency concluded that an 11-hour driving time provision 
combined with a 14-hour non-extendable driving window provide a greater 
opportunity for daily sleep compared to the pre-2003 rule, which 
allowed for a 15-hour extendable driving window with only 8 hours off 
duty. The available research and crash data do not clearly indicate 
whether the 11th hour of driving, combined with other provisions of the 
2003 rule, poses a significant safety risk to drivers. Since industry 
and Agency data show that the 11th hour is not fully utilized, any 
safety risk to drivers is lower than the possible worst case scenarios, 
which assume full use of all allowable driving hours, would suggest. In 
sum, it is the Agency's best judgment that the potential safety 
benefits to eliminating the additional one hour of driving are not 
great enough to justify the high cost of such a change. As noted above, 
the 10-hour off-duty period ensures that all drivers, including those 
utilizing a sleeper berth, have an opportunity to obtain an 
uninterrupted block of 8 consecutive hours so that fatigue is 
eliminated, or significantly reduced, on a daily basis. Adopting a 10-
hour off-duty period is supported by NTSB's 1996 report finding that 
the most critical factors in predicting fatigue were the duration of 
the most recent sleep period prior to the crash, length of time since 
last sleep period, sleep over the preceding 24 hours, and split-sleep 
patterns. The Agency recognizes that drivers, beyond sleep, have other 
needs to attend to, including commuting, performing errands, and 
addressing other personal and family matters. The extra 2 hours beyond 
those needed for sleep ensures a driver can complete such tasks. The 
interaction between these provisions enables the vast majority of 
drivers to work and drive to the maximum permissible limits per day 
(even if they chose not to do so), without developing a cumulative 
sleep debt.
    Fourth, the Agency considers the 34-hour recovery provision to be a 
safety net for the other provisions in the exceptional case where a 
driver has not obtained sufficient rest, despite 10 hours off duty 
(including for sleeper berth drivers) combined with a 14-hour non-
extendable driving window. Given that the Agency has reduced the 
driving window requirement by 1 or more hours, the negative effects of 
longer weekly driving hours has been addressed on a daily basis. The 
Agency acknowledges that the recovery provision allows a driver to 
drive

[[Page 50039]]

additional weekly hours, but we believe the 34-hour period affords 
sufficient time for 2 nights of 8-hour sleep for the vast majority of 
drivers and an 18-hour intervening period of wakefulness that in 
combination allow for weekly recovery from any sleep debt accumulated 
by a driver over multiple days. In addition, night drivers will 
accumulate less fatigue on a daily or weekly basis compared to the pre-
2003 rule through the combined effects of the provisions discussed in 
this section. For night drivers, the two 8-hour sleep periods give 
drivers an adequate opportunity to help minimize acute and cumulative 
fatigue, regardless of their driving schedule. However, worst-case 
scenarios presented by commenters (and FMCSA in the NPRM) regarding 
total hours operators may drive under the 2003 rule are not realistic 
nor supported by operational and safety data (see rationale seven below 
for detailed discussion). Another major benefit to adopting a recovery 
period is that it allows drivers to begin their work schedule at 
approximately the same time each day as their last shift; hence, this 
will avoid shifting of daytime to nighttime schedules that research 
shows can disrupt the circadian rhythm by promoting fatigue and 
potentially higher crash risk. Also, because recovery can be taken at 
any time, it can be used when needed most by drivers to maximize 
safety.
    The Agency considered adopting a 44-hour recovery period. The 
Agency has concluded, however, there is no conclusive scientific data 
available at this time to guide us in determining which factor 
(recovery vs. circadian disruption) is more predictive in alleviating 
fatigue. Hence, considering a longer recovery period illustrates the 
profound complexity concerning this issue.
    The Agency has weighed the concerns with night driving and the 
benefits of night sleep; however, the fatigue risks of restricting 
night driving are outweighed by two counterproductive consequences: 
safety problems from increasing daytime traffic, and the significant 
economic impact on industry. For example, a 44-hour recovery period 
would cause the severe traffic-related and economic impacts described 
above (see Section J.8). After reviewing the combined effects of all 
the provisions compared to the pre-2003 rule, the Agency is adopting a 
34-hour recovery provision because it acts as a flexible, weekly safety 
net that will benefit the vast majority of drivers who fail to obtain 
daily rest with two extra hours (10 hours) of daily off-duty time 
(including sleeper-berth users), and a non-extendable (14-hour) driving 
window.
    Fifth, the Agency concluded that for drivers who take their 10-hour 
off-duty period in tandem with the 14-hour driving window (i.e., one 
after the other), these provisions collectively will help keep them on 
a 24-hour cycle, thereby mitigating or eliminating the deleterious 
effects of the circadian de-synchronization on driver sleep and 
alertness. There was near consensus among commenters that the combined 
effects of these provisions reduce fatigue, leading to positive safety 
benefits. The Agency believes that the 2003 rule's movement toward a 
24-hour cycle has helped to regularize drivers' schedules and thereby 
minimize fatigue. FMCSA acknowledges that neither the 2003 rule nor 
today's rule eliminates the possibility that drivers will utilize 
backward rotating schedules by combining driving and off-duty time, 
while minimizing other on-duty not-driving time (e.g., long-haul driver 
on day two of a trip that requires no additional loading). The change 
from an 18- to 21-hour cycle between the pre-2003 and 2005 rule reduces 
the likelihood and severity of drivers falling into backward rotating 
schedules that induce fatigue.
    Sixth, the Agency is creating a new regulatory regime for drivers 
of small, short-haul CMVs in today's rule that allows them to drive 
within a 16-hour window twice a week. This industry segment experiences 
less driving-related fatigue and poses a lower crash risk compared to 
the long-haul trucking operations also covered by this rule. Today's 
rule does not increase the maximum number of work hours (60- and 70-
hour rules are still applicable to short-haul drivers) or daily driving 
time (11-hour driving limit per day) allowed small, short-haul CMVs. 
This provision is expected to be utilized intermittently and to provide 
flexibility to meet seasonal and peak demands without leading to longer 
driving or significantly longer duty-tour times. Therefore, due to the 
unique attributes of the short-haul sector described below (and 
detailed in the short-haul section, J.10) and given that the limited 
number of added hours do not create a net increase in driving or duty 
hours over multiple days, this provision will not adversely impact 
drivers' health or safety.
    Short-haul drivers have an opportunity for daily and weekly fatigue 
recoveries that typically exceed those of other trucking sectors. 
Short-haul operators drive less than 40 percent of their total duty 
tour, and their driving tasks are broken up by frequent deliveries and 
light to moderate work-related physical activity. Both factors lead to 
less accumulation of driving-related fatigue compared to long-haul 
drivers. In addition, the regularity of typical short-haul drivers' 
schedules differs from other drivers in that they sleep at home each 
night, have 5-day schedules with limited weekend work, and usually are 
provided at least a 48-hour recovery period over the weekend, 
consistently providing the opportunity for two 8-hour nights of sleep.
    Based on the scientific literature analyzed by FMCSA, and when 
considered with the combined effect of other provisions enacted by this 
rule, the Agency concludes that this provision will not lead to 
negative health or safety impacts. FMCSA believes this 16-hour 
provision is justified under the continuous wakefulness literature 
discussed earlier which indicates that performance declines and crash 
rates increase beyond 16 hours of work. Although we have adopted a 14-
hour driving window provision discussed above for other categories of 
drivers, we believe this 16-hour provision is justified because (1) 
limiting the availability of this provision to two days per week will 
not negatively impact short-haul driver safety; (2) the enhanced 
opportunity for daily and weekly recovery in this unique industry 
segment creates a reduced fatigue risk, especially since these short-
haul provisions, when combined with the other provisions of the 2005 
rule, do not create a net increase in driving or duty hours over 
multiple days; and (3) the FMCSA Field Survey found that these drivers 
take 1-2 hour naps to reduce any daily fatigue that may occur.
    Since these drivers are typically on a fixed schedule, the Agency 
does not believe that the provision allowing two 16-hour duty tours 
each week will be used frequently, especially due to the disruption 
caused by the forward-rotation of the schedule. The Agency has found 
few studies discussing related health impacts; however, based on the 4 
hours of additional duty tour per week and the unique schedule and 
recovery periods typical to this sector, the Agency concludes there 
will be no deleterious impacts from this provision.
    Seventh, the agency concluded that the worst-case driver fatigue 
and health scenarios suggested by commenters regarding the 2003 rule's 
operational impact are not realistic. Most drivers are taking longer 
recovery periods than the minimum FMCSA is establishing under this 
rule, indicating that drivers value their rest and personal time and do 
not always seek to maximize driving time. Further, the average driver 
is not able to, and realistically cannot, drive and work

[[Page 50040]]

the longer weekly hours by utilizing the recovery provision on a 
regular basis, as described by some commenters. Another reason to doubt 
the worst-case scenarios advanced by certain commenters is that there 
is no clear data suggesting that fatigue-related crash risks have risen 
under the 2003 rule. In fact, FARS data show some decrease in such 
crashes. Moreover, numerous drivers reported that the 2003 rule's off-
duty time provided the opportunity not only for sleep, but also for 
relaxation and personal tasks. Consequently, their quality of life has 
been enhanced by the 2003 rule. Furthermore, even for drivers 
maximizing their driving time (11 hours of driving followed by 10 hours 
off duty) the resulting 21-hour cycle is closer to the ideal 24-hour 
cycle than the previous 18-hour ``day'' (10 hours of driving followed 
by 8 hours off duty). In sum, comments and data by drivers and industry 
representatives do not substantiate the worst-case scenarios advanced 
by commenters.
    In conclusion, the Agency believes that the combined cumulative and 
interaction effects of the provisions discussed above will result in 
less fatigue for drivers and thereby greater safety for the drivers and 
the public compared to past hours-of-service requirements.
Comments
    Health and Safety. Several commenters believe that the 2003 rule 
has beneficial impacts for both the health and safety of drivers. 
Regarding health, a commenter cited a potential decrease in sick days. 
Carriers report that drivers seem to be getting more sleep due to 
having two extra hours off-duty, giving them more time to relax and 
rest, which is facilitated by the establishment of a more routine 
schedule. The routine sleep schedule leads to better quality of sleep. 
The Distribution and LTL Carriers Association cited net benefits from 
having more time for rest, errands, and social matters, resulting in 
general driver satisfaction, which ordinarily leads to a healthy 
driver. J.G. MacLellan Concrete suggested that the health and safety of 
drivers is not impacted by the extra driving hours provided by the 2003 
rule because most of their drivers work on-site and are not utilizing 
such driving hours.
    Others characterized the cumulative health and safety impacts as 
negative. Specifically, Public Citizen made the point that the recovery 
provision adversely affects driver health and safety in two ways: It 
dramatically increases both weekly driving and duty hours while 
significantly curtailing much needed weekly rest.
    Interactions/offset. The Owner Operator Independent Drivers 
Association (OOIDA) stated that if there is any negative impact of the 
use of the 11th hour, it is more than compensated for by the aggregate 
benefits of a 24-hour clock and an additional 2 hours daily rest per 
day. Furthermore, FMCSA should not narrowly analyze whether the 1 or 
more hour reduction in on-duty time offsets the increase in 1 hour of 
driving time. Instead, the Agency should compare all of the benefits of 
the rule with any effects of the occasional use of the 11th hour of 
driving.
    Some parties discussed the health and safety aspects of individual 
provisions. NIOSH concluded that the current data are not adequate to 
characterize any acute health or safety consequences associated with 
the 14 hours of daily duty and 11 hours of driving under the 2003 rule. 
In addition, it is not feasible to conduct an epidemiological 
investigation of short-term effects for the 2003 rule.
    Citing a portion of our NPRM, AHAS stated that the Agency's effort 
to analyze the combined effects of health and safety issues that are 
``inextricably linked'' [70 FR 3343] ignores the court's request to 
treat health separately from fatigue and safety.
    24-hour cycle. Several commenters supported the rule's move toward 
a 24-hour circadian sleep cycle to benefit drivers' safety and health. 
For instance, the National Industrial Transportation League (NITL) 
maintained that by combining a 14-hour workday with the 10-hour off-
duty requirement, the HOS rule moves drivers toward a 24-hour cycle 
that approximates the body's natural circadian rhythm. The benefits of 
the 24-hour cycle include reduced stress and protection against other 
deleterious health impacts from abnormal sleep patterns. NITL also 
suggested that while a 21-hour day is unlikely because of the non-
driving tasks, such as breaks and inspections, that drivers must 
perform, it is superior to an 18-hour day. OOIDA noted that the 
adoption of both the 14 consecutive on-duty hours and 10 consecutive 
off-duty hours provisions has been helpful to some drivers in achieving 
a 24-hour schedule. OOIDA also noted that a 24-hour schedule is 
beneficial to a driver's overall safety and health on all performance 
measures. International Paper noted the importance of the circadian 
rhythms on a driver's health, physical condition, and alertness. They 
argued that such rhythms provide a strong rationale for the 34-hour 
recovery because a driver can take 10 hours of off-duty rest, take 24 
hours off, and begin work at the same time, thereby following the 
circadian rhythm.
    Others took issue with the Agency's effort to move towards a 24-
hour cycle. For example, Public Citizen challenged FMCSA's statement 
regarding our effort at moving toward a 24-hour work cycle, providing 
drivers with sufficient time off to obtain 8 hours sleep, while 
preserving flexibility for carriers in meeting schedule demands. They 
asserted that no studies cited by the Agency suggest safety and driver 
health will be improved by ``moving toward'' requiring a 24-hour work 
cycle or that a backward-rotating 21-hour schedule is any improvement 
over a backward-rotating 18-hour schedule.
FMCSA Response
    The following response addresses health and safety comments 
pertaining to interactions/offsets and the 24-hour cycle. In the 2005 
NPRM, FMCSA asked for information on combined effects of the provisions 
(driving time, duty time, and recovery) on ``driver health, the safe 
operation of CMVs, and economic factors.'' In the 2005 NPRM and in 
today's rule, FMCSA treated health and safety impacts independently 
pursuant to the court's request. Specifically, in the 2005 NPRM, in 
addition to asking how health and safety may be related, we devote four 
sections and five separate questions to specific health concerns [70 FR 
3344-3346]. AHAS asserts that we do not treat health and safety 
separately. The Court notes that while FMCSA must separately address 
driver health from safety, this does not ``suggest that the two factors 
are unrelated: Healthy drivers presumably cause fewer crashes and 
drivers who have fewer crashes suffer fewer injuries.'' AHAS seems to 
oversimplify the combined effects of these provisions that the court 
acknowledged.
    Based on the studies, data, and comments, FMCSA believes those 
drivers who take 10 hours off-duty in tandem with the 14-hour driving 
window are more likely to maintain their 24-hour cycle compared to 
drivers utilizing the pre-2003 rule, thereby increasing the probability 
that drivers using today's rule are alert. The rule we are adopting 
today does not eliminate the possibility that drivers could utilize 
backward rotating schedules by combining driving and off-duty time; 
however, the new rule is an improvement for drivers' circadian rhythm 
over the 18-hour ``day'' possible under the pre-2003 rule. 
Specifically, today's rule moves drivers from an 18- to 21-hour driving 
time/off-duty cycle, which is far closer to a 24-hour cycle

[[Page 50041]]

than the pre-2003 rule achieved, and reduces the severity of a 
backward-rotating schedule. In addition, the combined effects of the 
various provisions, including adding 2 hours of daily off-duty time, 
utilizing a 14-hour non-extendable driving window, and removing the 
split sleeper berth provision, allow for more rest to drivers than was 
possible under the pre-2003 rule. The Agency also concludes that the 
health impacts between the 11 and 10 hours of driving are 
inconsequential.
    As noted above, FMCSA is adopting the duty-tour and off-duty 
provisions first enacted in the 2003 rule. In the rule adopted today, 
the Agency further bolsters CMV driver health and safety by a new 
provision that eliminates the use of the split sleeper berth time to 
ensure that all drivers have the opportunity to obtain eight hours of 
consecutive sleep on a daily basis. While fatigue should be eliminated 
for most drivers on a daily basis, the recovery provision is adopted as 
a flexible safety net that will protect most drivers when fatigue is 
not eliminated on a daily basis. Moreover, despite potential risks from 
DE, today's rule neither causes or exacerbates those risks; therefore, 
the rule has no deleterious effects on CMV driver health. Based on the 
combined effects and interactions of provisions of today's rule, in the 
agency's best judgment, today's rule enhances the health and safety of 
CMV drivers.

J.12. Effective and Implementation Dates

    Only one commenter, the Commercial Vehicle Safety Alliance (CVSA), 
addressed the issue of when the proposed HOS rule should become 
effective. CVSA asked FMCSA to provide enough time for enforcement 
agencies and industry to make the appropriate changes required by any 
change in the HOS rules. It stated that the 8-month implementation 
period allowed for the 2003 HOS rules was barely enough time.
FMCSA Response
    Today's final rule is effective on October 1, 2005. The HOS rule 
adopted on April 28, 2003, became effective 30 days after publication, 
but drivers and motor carriers were required to continue complying with 
the previous regulations until January 4, 2004. That interval gave 
industry and enforcement officials a substantial amount of time to 
revise their HOS training materials, re-train personnel and, in some 
cases, reprogram computer equipment.
    FMCSA cannot use a similar implementation procedure for this rule 
because the D.C. Circuit vacated the 2003 rule, and the statute re-
instating it provides that the rule shall expire no later than 
September 30, 2005. Under Section 7(f) of the Surface Transportation 
Extension Act of 2004, Part V, the 2003 rule is automatically replaced 
when today's rule becomes effective. The Agency cannot retain, or 
require compliance with, the 2003 rule for an interim period while 
motor carriers, drivers, and the enforcement community prepare to deal 
with the new requirements adopted today.
    FMCSA recognizes that neither enforcement agencies nor the motor 
carrier industry will be able to implement the new regulations 
immediately upon the notice effective date. Some States require 
legislative action to conform their HOS statutes to this rule, though 
others adopt FMCSA's safety regulations by reference. All States, 
however, will have to revise their enforcement manuals, re-program 
their computers, and retrain roadside enforcement personnel. Motor 
carriers face a similar challenge to revise their internal compliance 
procedures and re-train large numbers of drivers, dispatchers, and 
other staff. Therefore, prior to the effective date of today's final 
rule, the Agency will issue a policy statement announcing its 
expectations for compliance and enforcement during the first several 
months after it takes effect.

J.13. Electronic On-Board Recording Devices

    Approximately 170 comments were submitted addressing EOBRs. Of 
these, 124 commenters expressed general opposition to the required use 
of EOBRs, while 46 commenters favored their use. Of the 122 drivers who 
discussed EOBRs, 34 of them (28 percent) were in favor of a rule 
requiring their use. Seven trucking and other industry associations 
lined up against an EOBR requirement, while two safety advocacy groups 
strongly supported such a requirement.
FMCSA Response
    FMCSA has published an ANPRM (69 FR 53386, September 1, 2004) 
requesting information about factors the Agency should consider in 
developing performance specifications for EOBRs. As the Agency said in 
the preamble to that document, ``FMCSA is attempting to evaluate the 
suitability of EOBRs to demonstrate compliance with the enforcement of 
the hours-of-service regulations, which in turn will have major 
implications for the welfare of drivers and the safe operation of 
commercial motor vehicles.'' The ANPRM asked for comments and 
information, both on technical questions relating to EOBRs and about 
the potential costs and benefits of such devices. The Agency is 
actively collecting and analyzing data on the costs and benefits of 
EOBR use to industry. Beyond cost issues, developing rules or technical 
specifications for EOBR devices is a highly complex endeavor. In 
addition, such technology issues must be evaluated in the context of 
developing and implementing effective new compliance and enforcement 
policies. In short, the complexity of the technical and policy issues 
involved in EOBRs warrants a separate rulemaking effort. Therefore, 
comments on EOBRs are not addressed in this rulemaking. However, the 
EOBR rulemaking will consider alternative means to effect HOS 
compliance through that technology. FMCSA has provided copies of the 
EOBR-related public comments to the ongoing EOBR rulemaking docket 
(FMCSA-2004-18940). Any additional comments on EOBRs should be 
addressed to that docket.

J.14. Other Provisions

Exemption for Utility Service Vehicle Drivers
    Complete exemption from the HOS rule for operators of utility 
service vehicles (USVs) was suggested in a comment from The Edison 
Electric Institute (EEI). Twenty-five other commenters, including 
utility companies, workers, and associations, supported EEI's 
arguments. These comments noted that Congressional committees have 
recognized a need for special treatment of the utility industry in the 
HOS rules, and stated that a number of State and local regulatory and 
emergency response agencies support an exemption. Commenters stated 
that, unlike other CMVs, USVs are driven only a fraction of the total 
time the vehicles are in use, so there is less potential for fatigue-
related crashes. They typically are driven locally for a few hours a 
day or less, have low mileage, do not transport freight, and are used 
as mobile tools. These commenters argued that the special safety 
responsibilities and operating characteristics of the utility industry 
had not been considered in the rulemaking. They asserted that FMCSA had 
presented no evidence that including USVs in the rule would improve 
highway safety. Nor, they said, would an exemption for USVs impinge on 
the Agency's goals of improving safety for the commercial driving 
industry. The American Gas Association

[[Page 50042]]

argued that in the past FMCSA had failed to adequately consider utility 
industry arguments for exemption.
    The Edison Electric Institute argued that crash rates were lower 
for USVs than for CMVs in general, for CMVs operating within 100 air-
miles of their point of origin, and for all large trucks. EEI said that 
FMCSA had not shown that USVs operating during ``emergencies'' have a 
detrimental effect on safety. Seven commenters supported those 
comments. Three were utility companies whose own experience showed a 
low or negligible number of accidents caused by employee fatigue.
    The Commercial Vehicle Safety Alliance opposed a broad exemption 
for USVs. CVSA argued that emergency situations were generally already 
addressed by other rules, and concluded, based on MCMIS data ``that the 
utility industry's safety record is no better than the rest of the 
trucking industry that is subject to the hours-of-service rules. In 
fact, one could argue that based on this data the utility industry is 
overrepresented in fatalities compared to other segments of the 
industry.''
FMCSA Response
    FMCSA previously addressed exemption requests from utility 
companies, and has considered the issue again in this rulemaking. The 
Agency continues to believe that existing exemptions applicable to USVs 
provide a proper balance between operational needs and public safety. 
The regulations at 49 CFR 390.23 already provide an HOS exemption for 
USVs operating in local or regional emergencies. Some commenters noted 
that the types of ``emergencies'' cited by the utilities (e.g., downed 
power lines) occur frequently. The Agency believes USV operators 
should, therefore, be able to adjust the work schedules of their 
employees to ensure that drivers who have not reached their maximum 
limits under Part 395 are available when needed to handle these 
recurrent ``emergencies.'' As for the relative safety of utility 
operations, compiled crash data for this group of drivers is not 
extensive enough to be conclusive.
Outside Scope of Rulemaking
    Some comments to the docket discussed a variety of topics outside 
the scope of this rulemaking. For example, the National Ready Mixed 
Concrete Association (NRMCA) sought a change in the Part 395 definition 
of ``driving time.'' It stated that about 23 percent of the truck fleet 
in the ready-mixed concrete industry is composed of front-discharge 
mixers, which dispense concrete by means of a chute on the front of the 
truck. NRMCA stated that front-discharge mixer drivers are an anomaly 
with respect to the current definition of driving time. Operators of 
rear-discharge mixers have to exit the truck to dispense concrete from 
the rear, thus the time spent dispensing concrete is classified as on-
duty, not driving. A key element of the front-discharge design is that 
the driver can remain in the driver's seat to operate the mixer 
controls. During this time on the job site, the driver is at the 
controls of the CMV, meaning that this time must be classified as on-
duty, driving, but the driver is in fact not actually driving. To 
rectify this claimed misclassification of driving time, NRMCA 
recommended that FMCSA alter the definition of driving time to be ``all 
time spent at the controls of the CMV in operation on public roadways'' 
to more accurately capture ``on-duty, driving'' time versus ``on-duty, 
not driving'' time.
FMCSA Response
    Because this issue was not raised for comment in the NPRM, the 
Agency lacks the information to evaluate the implications of the NRMCA 
proposal. In this rulemaking, FMCSA will take no action on this issue.
    FMCSA may consider these topics for future rulemaking as 
appropriate.
Outside Jurisdiction of Agency
    Several topics addressed by commenters are not within the statutory 
authority of FMCSA. The Agency has no jurisdiction over any shippers 
and receivers, except to enforce certain hazardous materials 
regulations adopted from its sister DOT Agency, the Pipeline and 
Hazardous Materials Safety Administration, formerly the Research and 
Special Programs Administration. FMCSA also has no authority to 
regulate a driver's pay or other compensation. The Agency has 
acknowledged potential problems involving shortages of truck parking 
space, and has worked with other agencies and organizations to address 
the issue. However, FMCSA has no authority over any public or private 
property used for parking. Because FMCSA does have jurisdiction over a 
CMV driver, the Agency may prohibit or limit the driver from parking 
the vehicle in certain situations, but the Agency cannot require anyone 
to allow parking.
Alaska HOS
    Although not mentioned by commenters to this docket, FMCSA is aware 
that technical amendments (which do not require advance public notice 
and comment) are needed to correct inconsistencies in 49 CFR 395.1 (g) 
and (h) relating to HOS in the State of Alaska. Those sections have 
been revised to clarify the text in a manner consistent with current 
Agency policy and interpretation.

J.15. Legal Issues

Procedural Issues
    Seven commenters, including two labor unions, three trade 
associations, and two advocacy groups, expressed disapproval of the 
approach FMCSA had taken in the NPRM. The Transportation Trades 
Department of the AFL-CIO asserted that the NPRM did little more than 
challenge outside groups to demonstrate that some other rule or 
combination of provisions would be less harmful than the vacated rule. 
The International Brotherhood of Teamsters (IBT) argued that the 
language of the NPRM indicated that FMCSA had no intention of complying 
with the Court of Appeal's mandate to revise the HOS rule, and was 
instead seeking to shift the burden of proof to the opponents of the 
rule. IBT asserted that the NPRM invited opponents, by submitting 
additional scientific information, to demonstrate that the rule did not 
adequately comply with the statutory requirements. Instead, to comply 
with the court's decision FMCSA should have reexamined the scientific 
data already in the docket and addressed directly the documented health 
effects of chronic sleep deprivation, such as increased sensitivity to 
insulin, and increased risk of heart disease, hypertension, and 
obesity. In particular, FMCSA should not have published the NPRM before 
the literature review being conducted by the Transportation Research 
Board was completed and incorporated into the rulemaking.
    The National Association of Wholesalers and Distributors argued 
that the content of the NPRM failed to shed any light on the thinking 
of FMCSA, and that this was a misuse of the regulatory process. The 
American Bakers Association also strongly objected to the regulatory 
approach followed in the NPRM, which it characterized as an attempt to 
thrust onto the regulated community the Agency's responsibility to 
justify the regulatory initiative through extensive and detailed 
scientific and technical data.
    Two advocacy groups, Public Citizen and Advocates for Highway and 
Auto Safety (AHAS), strongly disapproved of the approach followed in 
the NPRM on a number of grounds. First, according to Public Citizen, 
the Agency did not ``go back to the drawing board'' and draft a

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new rule incorporating some of the best aspects of the 2003 rule, such 
as the shortened daily on-duty period, nor did it include safeguards 
from the old rule, such as the weekly driving hour limits. According to 
AHAS, ``[t]he notice neither provides any indication of what, if any, 
changes to the [April 2003] HOS regulations the Agency is considering, 
nor how it plans to resolve the issues raised in the Court's opinion.'' 
Because the notice did not narrow the possible issues or focus public 
comment on specific actions under consideration, AHAS argued, the 
notice ``is equivalent to an advance notice of proposed rulemaking, but 
does not rise to the level of a NPRM within the meaning of the 
Administrative Procedures [sic] Act (APA).''
    Commenters also requested FMCSA to leave the record open so that 
useful data, such as the 2004 NHTSA crash data, could be provided. The 
Truckload Carriers Association (TCA) said that the short comment period 
had diminished its ability to provide evidence, and that keeping the 
docket open was essential. AHAS and Public Citizen asked that the 
Agency provide time for the public to examine and comment on the 
literature review being conducted by the Transportation Research Board 
(TRB) of the National Academy of Sciences.
FMCSA Response
    Rulemaking as complex as this action would normally require several 
years to complete. The entire process had to be compressed into one 
year, because that was the time provided by Sec. 7 (f) of the Surface 
Transportation Extension Act of 2004, Part V. The Agency alluded to 
this dilemma in the NPRM and explained its effort to reconcile the 
requirements of notice and comment rulemaking with the realities of an 
expanding, time-consuming research program needed to address the issues 
raised by the court. ``In order to allow effective public participation 
in the process before the statutory deadline, FMCSA is publishing this 
NPRM concurrently with its ongoing research and analysis of the issues 
raised by the court. To facilitate discussion, the Agency is putting 
forward the 2003 rule as the ``proposal'' on which public comments are 
sought. This NPRM, however, asks the public to comment on what changes 
to that rule, if any, are necessary to respond to the concerns raised 
by the court, and to provide data or studies that would support changes 
to, or continued use of, the 2003 rule'' [70 FR 3339].
    As the quotation marks around ``proposal'' indicate, the 2003 rule 
was merely the starting point of a research and rulemaking program to 
determine whether that rule could be reconciled with the Public Citizen 
decision. Most of the critical comments summarized above simply 
overlooked the fact that FMCSA did not have enough time in one year 
sequentially to complete its research on a wide variety of issues, 
prepare and publish an NPRM, accept and analyze comments, make 
necessary changes to the regulatory proposal, submit the draft for 
intragovernmental review, and publish a final rule. Instead, the Agency 
opted for a parallel process; the public was asked to comment on 
changes to the 2003 rule that might be needed to comply with the 
court's decision, while the research and analysis on driver health and 
other issues identified by the court went forward simultaneously. There 
is no principle of administrative law that requires an Agency to 
forswear the search for additional information in an NPRM; on the 
contrary, agencies always seek new information from commenters.
    This parallel procedure is fully consistent with the requirements 
of the Administrative Procedure Act. The provisions of the 2003 rule 
that FMCSA has adopted in this rule were, of course, proposed in detail 
in the NPRM. To the extent revisions have been made, they are in 
response to issues raised in the NPRM. For example, the discussion of 
sleeper berths included the statement that ``FMCSA will consider a 
variety of possible changes to the sleeper-berth provisions, including 
but not limited to: * * * (2) allowing one continuous sleeper-berth 
period of less than 10 hours, such as 8 hours, to substitute for the 
otherwise minimum 10 hours'' [70 FR 3349]. After examining a variety of 
alternatives, the Agency adopted that very option. The NPRM also 
discussed the unique operational conditions affecting local or short-
haul drivers and concluded that, ``[s]ince local short-haul drivers 
typically work daytime hours, they are much more likely to maintain 
regular schedules that are less intense than many long-haul drivers. 
Short-haul drivers are significantly less likely to be working 13 or 
more hours or to have irregular circadian patterns. Also, local short-
haul drivers typically sleep at home every night in their own beds. 
Thus local short-haul drivers are much more likely to be getting the 
daily restorative sleep necessary to maintain vigilance'' [70 FR 3351]. 
The Agency's new regulatory regime for drivers of short-haul vehicles 
that do not require a CDL is strongly foreshadowed by these passages.
    In the NPRM instructions we were particularly interested in how 
various provisions impacted different sectors of the industry as we 
considered our regulatory options. We specifically asked in our 
guidance for commenters to provide information on the current type of 
operations, including ``(a) whether your primary operations are short-
haul (i.e., operations limited to 150 miles or less, with drivers 
typically spending the night at home) or long haul.''
    FMCSA has always allowed the docketing of information submitted 
after the comment period closes. The NPRM said that ``[c]omments 
received after the comment closing date will be included in the docket 
and we will consider late comments to the extent practicable. FMCSA 
may, however, issue a final rule at any time after the close of the 
comment period.'' The Agency accepted and read many comments filed 
after the closing date (March 10, 2005), and posted additional material 
to the docket as it became available.
Driver Health
    Both Public Citizen and AHAS argued that the NPRM sought to create 
a misleading and improper focus on the vacated 2003 rule and the issue 
of whether that rule should be changed. Public Citizen found it 
unacceptable for FMCSA to frame the discussion regarding driver health 
as if the 2003 final rule was an acceptable baseline against which 
modifications should be judged. AHAS similarly argued that the proposal 
continued to promote the invalidated April 2003 HOS final rule, 
notwithstanding its wholesale rejection by the Court of Appeals.
    Both argued that the NPRM also incorrectly sought to narrow the 
scope of the Agency's responsibility to safeguard driver health (Public 
Citizen) or tried to avoid distinguishing between safety effects and 
health effects, as the Court of Appeals had required (AHAS). They both 
accused FMCSA of seeking to address only injuries or health conditions 
directly related to the HOS regulations and operation of a CMV, not 
other workplace injuries or health conditions suffered by drivers. AHAS 
argued that the NPRM's focus should have been broader than driver 
injuries resulting from crashes or adverse health impacts attributable 
to the act of driving. In AHAS's view, the issue of fatigue, alertness, 
and safe driving was factually and legally distinct from the issue of 
the health, physical condition, and well-being of truck drivers, but 
throughout the NPRM driver health, safe operation, and economics were 
treated as inextricably linked factors whose effects could not be 
separated and dealt with individually.

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    Finally, both Public Citizen and AHAS argued that the NPRM failed 
to provide any scientific support for the crucial elements of the 
Agency's proposal. Public Citizen stated that the proposal ``flies in 
the face'' of scientific evidence. AHAS asserted that the NPRM 
contained ``not a scintilla of data and scientific evidence'' that 
FMCSA had produced and applied any information with which to assess and 
compare the health effects of the pre-2003 HOS rule and the health 
effects of the April 2003 HOS regulation. No scientific information had 
been placed in the rulemaking record showing that drivers obtained more 
sleep under the new rule than under the old rule; or that they were 
more alert and had less fatigue; or that the new regulation had 
discernible safety benefits. AHAS asserted that FMCSA could not satisfy 
its statutory responsibility to consider existing scientific literature 
by asserting, as it did in the NPRM, that ``[t]he implications of these 
studies are not always clear.'' AHAS concluded that the NPRM did not 
satisfy either FMCSA's legal burden or its statutory obligation, 
arguing that the Agency had not demonstrated in the NPRM ``any 
intention to actively engage in a rulemaking action that directly 
confronts the application of existing research on worker health and 
physical condition to appropriate amendment of the current HOS 
regulation. Moreover, the Agency has failed to address its legal and 
statutory duty to ensure that the regulations it promulgates does [sic] 
not have a deleterious impact on truck driver health, physical 
condition, and well being.''
FMCSA Response
    The alleged deficiencies in the Agency's approach to driver health 
are answered by the discussion of that issue elsewhere in this 
preamble. FMCSA did not treat the 2003 rule as the baseline for 
analyzing driver health, as charged by Public Citizen. The Agency 
essentially used the pre-2003 regulations as the baseline. In any 
event, the effect on driver health of the HOS changes made in the 2003 
rule proved to be inconsequential. As for AHAS's charge that FMCSA 
improperly linked health, safety and economic considerations, rather 
than dealing with them individually, the Agency is required by statute 
to consider the costs of any regulations it believes necessary, 
including those to protect driver health [49 U.S.C. 31136(c)(2) and 
31502(d)]. Although the Agency ultimately determined that no such 
regulations were needed, the health data examined proved too uncertain 
to allow a reliable calculation either of the benefits or the cost of 
such a regulation. This is discussed more fully in section E.2, dealing 
with exposure to diesel exhaust.
Docketing Issues
    Public Citizen stated that ``FMCSA has haphazardly provided only 
abstracts in the docket for a number of studies that the Agency cites 
in this rulemaking notice, citing copyright protection concerns. This 
is a completely illegitimate claim. FMCSA may not base any rulemaking 
on materials not made publicly available and open to public scrutiny 
and comment. To do so would be a violation of the transparency 
requirements of the Administrative Procedures [sic] Act (APA). * * * 
FMCSA may not rely for its decision on any study for which it has 
provided only an abstract.'' In a supplemental comment, Public Citizen 
identified 23 studies provided only in abstracts; five of these had 
been available in full in the docket of the 2003 rule. The group 
asserted that the 2003 docket made available many copyrighted 
documents, and added that this docket apparently had been modified to 
substitute an abstract for a paper that was originally part of the 
docket. AHAS also objected to the posting of abstracts, rather than 
complete copies, of some studies.
FMCSA Response
    FMCSA placed abstracts of the copyrighted reports in the docket 
well before the close of the comment period. The abstracts identified 
the research under review by the Agency, summarized the conclusions of 
the authors, and supplied publication details. As FMCSA noted in 
correspondence responding to AHAS' concern over the abstracted reports, 
the full versions of the reports were readily available in the Library 
of Congress, the National Library of Medicine in Bethesda, and other 
sources such as university libraries. AHAS therefore could have 
obtained copies to review when those abstracts were docketed. FMCSA is 
not aware of any APA requirement that the Agency produce the complete 
text of copyrighted studies which are otherwise reasonably obtainable 
from other sources. Nonetheless, FMCSA has created a reading room where 
the copyrighted materials referred to in the NPRM may be examined 
[Department of Transportation, Nassif Building, 400 Seventh St., SW., 
Room 403, Plaza Level, Washington, DC].

K. Rulemaking Analyses and Notices

K.1. Executive Order 12866 (Regulatory Planning and Review) and DOT 
Regulatory Policies and Procedures

Overview
    The FMCSA received numerous comments regarding the economic impacts 
of the 2003 rule with regard to daily driving time, daily on-duty and 
off-duty periods, the recovery period, and combined economic effects. 
Today's preamble has discussed these comments separately as part of its 
individual discussions of those issues. As such, comments concerning 
the economic impacts of individual provisions will not be addressed in 
detail here. However, several comments were received regarding other 
cost impacts of the 2003 rule, as well as limitations of the models 
used in the 2003 regulatory impact analysis (RIA). See the RIA document 
in the docket for more details.
    Several commenters stated that they would incur additional employee 
training costs if further changes were made to the HOS rules. Some also 
commented that they would incur software reprogramming and update costs 
due to their use of electronic logbook software. The FMCSA recognizes 
that today's rule will result in new costs to motor carriers to train 
their drivers and other employees. As such, the RIA prepared for 
today's rule estimated employee training costs to motor carriers and 
drivers as part of its estimate of the total costs. Details regarding 
these costs are included in the RIA summary that follows this 
discussion, as well as in the separate RIA, entitled ``Regulatory 
Impact Analysis and Small Business Analysis for 2005 Hours of Service 
Regulatory Options,'' contained in the docket. Regarding software 
costs, not enough information was available on overall use of 
electronic logbook software to explicitly estimate such costs to the 
industry. However, such costs are indirectly estimated in this 
rulemaking as part of estimating the dollar cost of record of duty 
status (RODS) paperwork burden to industry from today's rule. The 
Agency's paperwork burden document, entitled ``Supporting Statement for 
Driver Hours of Service Regulation,'' is contained in the docket.
    Advocates for Highway and Auto Safety (AHAS) commented to the 2005 
NPRM docket that ``the Agency failed to account for the increased risk 
of crashes as time-on-task commensurately increases in its final 
benefit-cost analysis' and Public Citizen commented that FMCSA's RIA 
made ``no attempt to take time-on-task into account.'' In

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developing its RIA for today's rule, the Agency updated the sleep-
performance model used to estimate the safety impacts of the 2003 rule. 
To incorporate the potential effects on safety in the most 
comprehensive way, the Agency used a commercially-available computer 
program called the ``FAST/SAFTE'' Model. This program is designed to 
take workers'' schedules and predict their level of performance at each 
point in time. These performance levels were then used to estimate 
changes in crash risks for those time periods when the simulated 
operations schedules showed that the truck drivers were at the wheel 
(and thus vulnerable to crashing). The FAST/SAFTE Model is able to 
predict changes in drivers' levels of performance caused by varying 
degrees of sleep deficits over recent days and weeks. In addition, it 
accounts for a driver's circadian rhythms, and predicts the degree to 
which performance is degraded by driving at certain times of day or in 
certain parts of a daily cycle. The disruptive effects of rapid changes 
in circadian rhythms are also taken into consideration. However, 
according to our research, all currently-available, peer-reviewed 
sleep-performance models, including the FAST/SAFTE Model, are limited 
in their ability to take time-on-task (TOT) effects explicitly into 
account. The Agency corrected for this limitation by adding an 
independent TOT multiplier to the results of the FAST/SAFTE model. 
Despite the limitations of the available data, as was noted earlier in 
this preamble, FMCSA addressed TOT effects in its modeling and did so 
by basing its TOT multiplier on data from the Trucks Involved in Fatal 
Accidents (TIFA) database [Campbell, K.L. (2005), p. 8], which examined 
the number of trucks involved in fatigue-related fatal crashes by 
driving hour.
Options Considered
    After reviewing almost 1,800 written comments submitted in response 
to the 2005 NPRM, current safety research, and recently compiled 
industry operations data, FMCSA identified four regulatory options for 
detailed economic benefit-cost analysis.
     Option 1 is to readopt provisions of the 2003 rule, which 
allow up to 11 hours of driving within a consecutive 14-hour tour of 
duty; minimum consecutive 10 hours daily off-duty period, or 
alternatively allowing each 10-hour off-duty period to be split into 
two periods of at least 2 hours each, provided a sleeper berth is used 
and certain other requirements are met; and drivers to re-start their 
60- or 70-hour on-duty count after 34 hours of consecutive off-duty 
time.
     Option 2 (today's rule), allows 11 hours of driving in a 
tour of duty, restricts the splitting of off-duty time in sleeper 
berths to ensure that there is one period of at least 8 hours and 
counts the shorter part of a split period against the 14-hour tour-of-
duty clock; and allows drivers to re-start their 60- or 70-hour on-duty 
count after 34 hours of consecutive off-duty time.
     Option 3 does not allow more than 10 hours of driving or 
the splitting of off-duty periods, and requires 58 hours off before 
restarting.
     Finally, Option 4 is a variant on Option 3 that allows 
operators to restart the \7/8\-day clock by taking a 44-hour off-duty 
period. It is intended to test whether the costs of a much longer 
restart or recovery period can be mitigated while keeping some of the 
presumed fatigue-reducing benefits of a longer break.
    It should be noted here that Options 2 through 4 include the new 
short-haul regulatory regime, so there are no cost differences among 
the Options with regard to short-haul operational changes.
    Baseline for the analysis. According to Office of Management and 
Budget (OMB) guidance in OMB Circular A-4, the benefits and costs of 
each regulatory alternative must be measured against a baseline. The 
OMB guidance to Federal agencies states that the baseline ``should be 
the best assessment of the way the world would look absent the proposed 
action.'' [Office of Management and Budget, Circular A-4, 2003]. In 
most cases this would be the current operating or existing regulatory 
environment, and the impacts of all regulatory alternatives must be 
measured against this baseline. FMCSA first consulted with OMB to 
ensure that the baseline chosen for this RIA, the current operating 
environment, was the most appropriate starting point for the RIA. In 
discussions with OMB, it was decided that the current operating 
environment prior to today's rule was the most appropriate baseline for 
this analysis for several reasons. Industry is currently operating 
under the 2003 rule and the RIA must provide an estimate of the 
marginal or incremental economic impacts of potential Federal 
regulatory changes for use by decision makers.
    Please note, however, that the relative ranking of the options 
described and analyzed in the RIA would not be affected by the choice 
of a baseline. For example, although we believe that the 2003 rule is 
the most appropriate baseline for this analysis, it may also have been 
of interest to use the pre-2003 rule as a baseline for the analysis. 
Compared to the current analysis, using the pre-2003 baseline would 
have meant that the values for costs and benefits of each option would 
have changed, but their relative rankings would have remained intact, 
since the values for costs and benefits would have changed by the same 
amount under each option (as represented by the difference between the 
pre-2003 rule and the 2003 rule).
    Using the pre-2003 rule as a baseline, however, may have affected 
the choice of options in one respect. For instance, if, using the pre-
2003 baseline, the 2003 rule had negative net benefits that were larger 
than the positive net benefits seen under Option 2 using the 2003 
baseline, then the net benefits of Option 2 relative to the pre-2003 
rule would be negative, and adopting the pre-2003 rule would maximize 
net benefits. Fortunately, the Agency has already substantially 
evaluated the marginal economic impacts of the 2003 rule (a copy of 
which is contained in the docket), so the evaluation for today's rule 
could be considered in some respects the second phase of a two-phase 
evaluation of the economic effects between the pre-2003 rule and 
today's rule.
    According to the 2003 RIA, the 2003 rule resulted in net benefits 
totaling $1.1 billion annually, relative to the pre-2003 rule. Since 
the adoption of the 2003 rule, however, the analysis of HOS regulations 
has advanced in a number of important ways that could have affected the 
regulatory impact analysis of the 2003 rule. In other words, had the 
agency fully updated the 2003 RIA using the latest available data and 
analytical methodology, it is probable that the net benefits would be 
different. For instance, the agency has included a substantial revision 
to the model to allow for TOT effects, and has explicitly accounted for 
shifting circadian rhythms resulting from a driver's schedule changes.
    The agency concludes, however, that the net benefits of the 2003 
rule relative to the pre-2003 rule would remain highly positive. This 
conclusion is based on several factors. First, the available data on 
risk since the 2003 rule was put in place indicates a lower crash risk, 
as the agency concluded in the 2003 analysis. Although these data are 
not comprehensive, ma