Federal Register, Volume 75 Issue 17 (Wednesday, January 27, 2010)

[Federal Register Volume 75, Number 17 (Wednesday, January 27, 2010)]
[Proposed Rules]
[Pages 4323-4331]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-1656]

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DEPARTMENT OF LABOR

Occupational Safety and Health Administration

29 CFR Part 1910

[Docket No. OSHA-2007-0007]
RIN 1218-AC39

Additional Quantitative Fit-testing Protocols for the Respiratory
Protection Standard

AGENCY: Occupational Safety and Health Administration (OSHA), Labor.

ACTION: Proposed rule; withdrawal.

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SUMMARY: After thoroughly reviewing the comments and other information
available in the record for the proposed rulemaking, OSHA concludes
that the revised PortaCount[supreg] quantitative fit-testing protocols
are not sufficiently accurate or reliable to include among the
quantitative fit tests listed in Part II of Appendix A of its
Respiratory Protection Standard. Therefore, OSHA is withdrawing the
proposed rule without prejudice, and is inviting resubmission of the
revised protocols after developers of the protocols address the issues
described in this notice.

DATES: The proposed rulemaking is withdrawn as of January 27, 2010.

FOR FURTHER INFORMATION CONTACT: General information and press
inquiries: Contact Ms. Jennifer Ashley, Office of Communications, Room
N-3647, OSHA, U.S. Department of Labor, 200 Constitution Avenue, NW.,
Washington, DC 20210; telephone (202) 693-1999.
Technical inquiries: Contact Mr. John E. Steelnack, Directorate of
Standards and Guidance, Room N-3718, OSHA, U.S. Department of Labor,
200 Constitution Avenue, NW., Washington, DC 20210; telephone: (202)
693-2289; facsimile: (202) 693-1678.
Copies of this notice: Electronic copies of this Federal Register
notice, as well as news releases and other relevant documents, are
available at OSHA's Web page at http://www.osha.gov.

SUPPLEMENTARY INFORMATION:

I. Background

Appendix A of OSHA's Respiratory Protection Standard at 29 CFR
1010.134 currently includes three quantitative fit-testing protocols
using the following challenge agents: a non-hazardous generated aerosol
such as corn oil, polyethylene glycol 400, di-2-ethyl hexyl sebacate,
or sodium chloride; ambient aerosol; and controlled negative pressure.
Appendix A of the Respiratory Protection Standard also specifies the
procedure for adding new fit-testing protocols to the standard. The
criteria for determining whether OSHA must publish a fit-testing
protocol for notice-and-comment rulemaking under Section 6(b)(7) of the
Occupational Safety and Health Act of 1970 (29 U.S.C. 655) include: (1)
A test report prepared by an independent government research laboratory
(e.g., Lawrence Livermore National Laboratory, Los Alamos National
Laboratory, the National Institute for Standards and Technology)
stating that the laboratory tested the protocol and found it to be
accurate and reliable; or (2) an article published in a peer-reviewed
industrial-hygiene journal describing the protocol and explaining how
the test data support the protocol's accuracy and reliability. Using
this procedure, OSHA added one fit-testing protocol (i.e., the
controlled negative pressure REDON quantitative fit- testing protocol)
to Appendix A of

[[Page 4324]]

its Respiratory Protection Standard (see 69 FR 46986). OSHA also
published on December 26, 2007, a Notice of Proposed Rulemaking
requesting public comment on an abbreviated Bitrex[supreg] qualitative
fit-testing protocol (see 72 FR 72971). Subsequently, OSHA withdrew,
without prejudice, this fit-testing protocol from the rulemaking
process, and invited the developers of the protocol to conduct further
research addressing issues described in the withdrawal notice (see 74
FR 30250).

II. Summary and Explanation of the Withdrawal Notice

A. Introduction

In a letter submitting two new quantitative fit-testing protocols
for review under the provisions of Appendix A of OSHA's Respiratory
Protection Standard (Ex. OSHA-2007-0007-0001), Mr. Jeff Weed of TSI,
Inc., included a copy of a peer-reviewed article from an industrial-
hygiene journal describing the accuracy and reliability of these
proposed protocols (Ex. OSHA-2007-0007-0002).\1\ The submission letter
also included instructions that described in detail the equipment and
procedures required to administer the proposed protocols. According to
this description, the proposed protocols are variations of the existing
ambient-aerosol condensation-nuclei-counter quantitative fit-testing
protocol developed by TSI, Inc., in the 1980s, commonly referred to as
the PortaCount[supreg] quantitative fit-testing protocol (hereafter,
``the standard PortaCount[supreg] QNFT protocol''). OSHA included the
standard PortaCount[supreg] QNFT protocol in Appendix A of its final
Respiratory Protection Standard. (For consistency, OSHA will refer to
the two proposed protocols as ``revised PortaCount[supreg] quantitative
fit-testing protocols 1 and 2'' (i.e., ``revised PortaCount[supreg]
QNFT protocols 1 and 2'').
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\1\ This letter and the accompanying article describe three fit-
testing protocols, but Mr. Weed of TSI Inc., in a subsequent
telephone call to OSHA staff, requested that the Agency include only
two of them in the proposed rulemaking.
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The proposed protocols use the same fit-testing requirements and
instrumentation specified for the standard PortaCount[supreg] QNFT
protocol in paragraphs (a) and (b) of Part I.C.3 of Appendix A of the
Respiratory Protection Standard, with the following exceptions:
Revised PortaCount[supreg] QNFT protocol 1 reduces the
duration of the eight fit-testing exercises from 60 seconds to 30
seconds; and
Revised PortaCount[supreg] QNFT protocol 2 eliminates two
of the eight fit-testing exercises, with each of the remaining six
exercises having a duration of 40 seconds; in addition, this proposed
protocol increases the current minimum pass-fail fit-testing criterion
(i.e., reference fit factors) from a fit factor of 100 to 200 for half
masks, and from 500 to 1000 for full facepieces.
Peer-reviewed industrial-hygiene journal article. The peer-reviewed
article submitted by TSI, Inc., entitled `'Evaluation of Three New Fit
Test Protocols for Use With the TSI PortaCount[supreg],'' appeared in
the Fall/Winter 2005 issue of the Journal of the International Society
for Respiratory Protection (Ex. OSHA-2007-0007-0003). The article
describes a study that determined whether performing the proposed
protocols yields fit-testing results similar to results obtained with
the standard PortaCount[supreg] QNFT protocol (hereafter referred to as
``the Study'').\2\
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\2\ The standard PortaCount[supreg] QNFT protocol was the
criterion measure or ``gold standard.''
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Test subjects and respirator selection. The Study involved 30 test
subjects who performed 140 fit tests while wearing elastomeric half-
mask and full-facepiece respirators equipped with P100 filters. The
test subjects selected respirators from among 24 models, with some test
subjects using more than one model during fit testing. Respirator fit
varied across the test subjects, with 60 of 140 fit factors below 100,
and 91 of 140 fit factors less than 500, as determined by the standard
PortaCount[supreg] QNFT protocol. Poor respirator fit resulted from
improper respirator selection by the test subjects themselves, or from
assigning respirators to test subjects that were either too small or
too large. Test subjects could adjust the respirator for comfort, but
they did not perform user seal checks.
Procedures. In conducting the Study, the authors followed the
recommendations for evaluating new fit-testing protocols specified by
Annex A2 (``Criteria for Evaluating Fit Tests Methods'') of ANSI
Z88.10-2001 (``Respirator Fit-testing Methods''). Specially designed
testing software allowed for the calculation of fit factors every 10
seconds during the in-mask sampling periods without disturbing the
facepiece (i.e., at 10-, 20-, and 30-second intervals for comparison
with the 40-second in-mask sampling intervals determined using the
standard PortaCount[supreg] QNFT protocol). The authors used a TSI
PortaCount[supreg] Plus Model 8020[supreg] quantitative fit-test system
to assess respirator fit; the system used a TSI-supplied sampling
adaptor, or fixed probes provided by the respirator manufacturer, to
collect samples inside the respirators. The sampling point inside the
respirator was between the nose and the mouth. During sampling, the
test subjects performed the exercises listed in Part I.A.14 of Appendix
A of OSHA's Respiratory Protection Standard, which include: initial
normal breathing, deep breathing, turning the head side to side, moving
the head up and down, reading a passage, grimace, bending over, and
final normal breathing. The TSI PortaCount[supreg] Plus fit-testing
instrument performed particle counts on samples collected during the
Study. Table 1 provides the exercise and sampling parameters for each
of the protocols used in the Study.

Table 1
----------------------------------------------------------------------------------------------------------------
In-Mask sampling
Number of Duration of each duration for each
Protocol exercises exercise exercise
(seconds) (seconds) \1\
----------------------------------------------------------------------------------------------------------------
Standard PortaCount[supreg] QNFT Protocol.............. 8 60 40
Revised PortaCount[supreg] QNFT Protocol 1............. 8 30 10
Revised PortaCount[supreg] QNFT Protocol 2............. \2\ 6 40 20
----------------------------------------------------------------------------------------------------------------
\1\ Does not include 20 seconds for each exercise to collect ambient-air samples and to purge the in-mask and
ambient-air sampling tubes.
\2\ This protocol eliminated the initial normal-breathing exercise and the deep-breathing exercise.

[[Page 4325]]

Results. The Study results describe the performance of the two
revised PortaCount[supreg] QNFT protocols in relation to the reference
fit factors (RFFs) that the proposed protocols designate as pass-fail
criteria for half-mask respirators (100 and 200 for protocols 1 and 2,
respectively) and full-facepiece respirators (500 and 1000 for
protocols 1 and 2, respectively). However, OSHA could not evaluate the
results for each type of respirator separately because the analyses
performed in the Study grouped fit-testing results from half-mask
respirators with fit-testing results from full-facepiece respirators.
In this regard, Table III of the Study showed 69 fit tests for half-
mask respirators and 71 fit tests for full-facepiece respirators, for a
total of 140 fit tests. However, the results in Table III of the Study
also list 140 fit tests for RFFs < 100 and > 100, and another 140 fit
tests for RFFs < 500 or > 500, when the number of fit tests for each
set of RFFs should be 69 and 71, respectively (i.e., 69 fit tests for
RFFs < 100 and > 100, with these RFFs to be applicable to half-mask
respirators, and 71 fit tests for RFFs < 500 and > 500, with these RFFs
to be applicable to full-facepiece respirators).\3\
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\3\ RFFs > 100 include RFFs > 200, which were to be applicable
to half-mask respirators, while RFFs > 500 include RFFs > 1000,
which were to be applicable to full-facepiece respirators.
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Using the standard PortaCount[supreg] QNFT protocol as the
criterion measure, the Study described the fit-testing results obtained
with the revised PortaCount[supreg] QNFT protocols using the following
statistics: test sensitivity; predictive value of a pass; test
specificity; predictive value of a fail; and the kappa statistic. These
statistics derive from the variables defined by ANSI Z88.10-2001, in
which: A = false positives (passed the fit test with a fit factor <
RFF); B = true positives (passed the fit test with a fit factor >=
RFF); C = true negatives (failed the fit test with a fit factor < RFF);
D = false negatives (failed the fit test with a fit factor >= RFF); Po
= observed proportion of the two fit tests that are concordant; and Pe
= expected proportion of the two fit tests expected to be concordant
when the two tests are statistically independent. Using these
variables, ANSI Z88.10-2001 specifies the formula and recommended value
(``RV'') for each statistic as follows: Test sensitivity = C/(A + C),
RV >= 0.95; predictive value of a pass = B/(A + B), RV >= 0.95; test
specificity = B/(B + D), RV > 0.50; predictive value of a fail = C/(C +
D), RV > 0.50; and the kappa statistic = (Po-Pe)/(1-Pe). The following
tables list the values of these descriptive statistics for revised
PortaCount[supreg] QNFT protocols 1 (at RFFs of 100 and 500) and 2 (at
RFFs of 200 and 1000).

Table 2--Descriptive Statistics for RFFs of 100 and 200
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Revised Revised
PortaCount[supreg] PortaCount[supreg]
Statistics ANSI Requirement QNFT Protocol 1 QNFT Protocol 2
RFF = 100 RFF = 200
----------------------------------------------------------------------------------------------------------------
Sensitivity.......................................... >=0.95 \1\ 0.91 1.00
Predictive Value of a Pass........................... >=0.95 \2\ 0.94 1.00
Specificity.......................................... >0.50 0.99 0.81
Predictive Value of a Fail........................... >0.50 0.98 0.79
Kappa Statistic...................................... >0.70 0.91 0.78
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\1\ = Fail; \2\ = Borderline fail.

Table 3--Descriptive Statistics for RFFs of 500 and 1000
----------------------------------------------------------------------------------------------------------------
Revised Revised
PortaCount[supreg] PortaCount[supreg]
Statistics ANSI Requirement QNFT Protocol 1 QNFT Protocol 2
RFF = 500 RFF = 1000
----------------------------------------------------------------------------------------------------------------
Sensitivity.......................................... >=0.95 0.97 1.00
Predictive Value of a Pass........................... >=0.95 \1\ 0.94 1.00
Specificity.......................................... >0.5 0.98 0.84
Predictive Value of a Fail........................... >0.50 0.99 0.92
Kappa Statistic...................................... >0.70 0.94 0.87
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\1\ = Borderline fail.

For a RFF of 100, revised PortaCount[supreg] QNFT protocol 1 failed
to meet the sensitivity value specified by ANSI Z88.10-2001, and,
consistent with this failure, the value for the predictive value-of-a-
pass statistic was marginal. However, for a RFF of 500, the sensitivity
value for this proposed protocol exceeded the ANSI requirement,
although the predictive value-of-a-pass statistic was again slightly
below the ANSI specification. The failure of protocol 1 to achieve the
sensitivity value specified by ANSI Z88.10-2001 at a RFF of 100
indicates that the proposed protocol is susceptible to alpha, or false
positive, error--i.e., it would pass some half masks that would
function below a fit factor of 100 when tested with the protocol used
as the criterion measure (i.e., the standard PortaCount[supreg] QNFT
protocol). This failure to meet the sensitivity value specified by ANSI
Z88.10-2001 raises a question of whether revised PortaCount[supreg]
QNFT protocol 1 is as protective as the standard PortaCount[supreg]
QNFT protocol. For protocol 1, the authors reported values well above
the values established by the ANSI standard for the three remaining
statistics, including specificity, predictive value of a fail, and the
kappa statistic. However, the grouping of results for half-mask and
full-facepiece respirators brings the applicability of these statistics
into question.
For PortaCount[supreg] QNFT protocol 2, the sensitivity values for
both RFFs were well in excess of the sensitivity value specified by the
ANSI standard. The sensitivity values for this proposed protocol
indicate that it identified 100% of the poorly fitting half-mask and
full-facepiece respirators. In addition, this

[[Page 4326]]

proposed protocol performed well above the values listed in the ANSI
standard for the four remaining variables, including predictive value
of a pass, specificity, predictive value of a fail, and the kappa
statistic. Consistent with the sensitivity values derived for this
proposed protocol, these four values indicate that the proposed
protocol accurately determined whether respirators achieved, or failed
to achieve, RFFs of 200 and 1000. Nonetheless, as mentioned above, the
grouping of results for half-mask and full-facepiece respirators brings
the applicability of these statistics into question.
In discussing the results for revised PortaCount[supreg] QNFT
protocol 2, the authors asserted that excluding the two least strenuous
fit-testing exercises (i.e., the initial normal-breathing exercise and
the deep-breathing exercise) from this proposed protocol was a
conservative approach in that the proposed protocol was more likely
than protocols consisting of eight fit-testing exercises to detect
respirator leakage (i.e., using data from less strenuous fit-testing
exercises inappropriately inflates the overall fit factor for
respirators, thereby increasing alpha error). Another conservative
approach used by this proposed protocol was raising the RFFs for half
masks from a fit factor of 100 to 200, and, for full-facepiece
respirators, from 500 to 1000. While this approach may have enhanced
the sensitivity of the proposed protocol, it may also increase beta
(false-negative) error; beta error would increase the number of
repeated tests and, consequently, the total testing time required by
some employees to identify a respirator having an acceptable fit.

B. Decision To Publish the Two Protocols for Notice-and-Comment
Rulemaking

OSHA reviewed the information submitted by TSI, Inc., in support of
these proposed protocols to determine whether the protocols met the
criteria for determining whether OSHA must publish new fit-testing
protocols for notice-and-comment rulemaking established by the Agency
in Part II of Appendix A of its Respiratory Protection Standard. The
Agency concluded that the proposed protocols warranted notice-and-
comment rulemaking under Section 6(b)(7) of the Act (29 U.S.C. 655),
and initiated rulemaking to determine whether to approve these proposed
protocols for inclusion in Part I of Appendix A of its Respiratory
Protection Standard. OSHA published the proposal in the Federal
Register on January 21, 2009 (see 74 FR 3526).

C. Issues Raised for Public Comment

In the Federal Register notice announcing the proposal, OSHA
invited comments, information, and data from the public regarding the
accuracy and reliability of the proposed protocols, effectiveness of
the protocols in detecting respirator leakage, and the usefulness of
the protocols in selecting respirators that will protect employees from
airborne contaminants in the workplace. Specifically, the Agency
invited public comment on the following issues:
Were the studies described in the peer-reviewed journal
article well controlled, and conducted according to accepted
experimental design practices and principles?
Were the results of the studies described in this article
properly, fully, and fairly presented and interpreted?
Will the proposed protocols generate reproducible fit-
testing results?
Will the proposed protocols reliably identify respirators
with unacceptable fit as effectively as the quantitative fit-testing
protocols, including the standard PortaCount[supreg] QNFT protocol,
already listed in Part I.C.3 of Appendix A of the Respiratory
Protection Standard?
Is the test-sensitivity value of 0.91 obtained for half
masks by revised PortaCount[supreg] QNFT protocol 1 acceptable in view
of the test-sensitivity value of 0.95 required by ANSI Z88.10-2001; if
not, would it be appropriate for OSHA to limit application of revised
PortaCount[supreg] QNFT protocol 1 to full-facepiece respirators?
The Study evaluating the proposed protocols involved only
elastomeric half-mask and full-facepiece respirators. Accordingly, is
it appropriate to apply the results of the Study to other types of
respirators (e.g., filtering-facepiece respirators)?

D. Summary of the Public Comments Received

Twenty-six commenters submitted responses to the proposal. The
following paragraphs in this section address the responses made to each
of the six issues described previously.
1. Were the studies described in the peer-reviewed journal article well
controlled, and conducted according to accepted experimental design
practices and principles?
In addressing this issue, the National Institute of Occupational
Safety and Health (NIOSH) stated:

[The Study] does not provide sufficient detail about the study
design and protocol to enable a complete assessment of how well it
was controlled and conducted. The description in the article does
indicate that design and principles met acceptable practices.
However, the study design did not include filtering-facepiece
respirators (FFR), nor sufficient fit test trials for half-mask
respirators or full facepiece respirators to provide data that would
allow independent assessment of the performance of the proposed
revised protocols for either facepiece type. To fully assess the
acceptability of the new protocols for applicability to half-mask
respirators (including filtering-facepiece respirators) and full
facepiece respirators, each facepiece type needs to be evaluated
separately. The data analyses reported in the peer-reviewed journal
article grouped fit test results for the half-mask and full
facepiece respirators to obtain the minimum number for paired data
sets required by ANSI Z88.10-2001, Annex A2. (See Ex. OSHA-2007-
0007-0016.1.)

James S. Johnson (Ex. OSHA-2007-0007-0023.1) and Ching-tsen Bien
(Ex. OSHA-2007-0007-0017.1) both disapproved of the Study's
experimental design practices and principles, and specifically
criticized the grouping of results for half-mask and full-facepiece
respirators. OSHA agrees that grouping results for half-mask and full-
facepiece respirators in analyzing RFFs is a major limitation of this
study (see, also, the discussion of this issue in paragraph D.2 of this
section).
Similar to NIOSH, Ching-tsen Bien questioned the number of fit-test
trials performed in the Study. Mr. Bien stated: ``The ANSI Z88.10-2001
requires a minimum of 100-paired tests. The proposed protocol only
contains 69-paired tests for the half-mask, and 71-paired test sets for
the full facepiece. It failed to meet this requirement.'' In addition,
the American Federation of Labor and Congress of Industrial
Organizations (AFL-CIO) criticized the Study for using only 30
participants to generate fit-test data (Ex. OSHA-2007-0007-0015).
In response to the assertion that the Study did not consist of as
many fit tests as required under ANSI Z88.10-2001, OSHA emphasizes that
it has not adopted the criteria in ANSI Z88.10-2001 as absolute
requirements for new fit-testing protocols. Nonetheless, as NIOSH and
Mr. Bien note, it appears that the Study did not consist of a
sufficient number of fit tests to establish the respirator-specific
performance of the proposed protocols. In response to the AFL-CIO, OSHA
notes that researchers should, ideally, validate fit-testing protocols
on a large number of study participants to account for variability
across the population of employees who use the respirators. However,
OSHA believes the total number of study participants is less

[[Page 4327]]

important than the total number of fit tests the participants perform.
NIOSH also criticized the calculation of fit factors for the
proposed protocols that used subsets of measurements taken during a
standard PortaCount[supreg] fit-test (Ex. OSHA-2007-0007-0016.1). In
its comment, NIOSH stated:

For the results of the fit test using shortened exercises to be
similar to the reference protocol, the fit of the respirator must
not change significantly over time for each fit test exercise. The
data are inadequate to demonstrate reproducible fit-testing results
for either proposed protocol. Therefore, any subsequent assessment
of conformance or non-conformance with the ANSI Z88.10-2001
acceptance criteria cannot be presumed to be valid. Further
investigation is required to compare potential changes in fit across
the proposed 30- and 40-second exercise intervals in the reference
protocol * * *. No information is provided in either the peer-
reviewed journal article or application to OSHA that demonstrates
the proposed shortened exercise times would encompass the most
challenging aspects of each exercise. At a minimum, the frequency
and consistency of leaks during each exercise, as well as the
magnitude and type of those leaks (e.g. start of exercise, end of
exercise, throughout exercise period) need to be identified and
analyzed.

Clifton D. Crutchfield (Ex. OSHA-2007-0007-0019.1) and NIOSH (Ex.
OSHA-2007-0007-0016.1) also questioned the assertion by the Study's
authors that removal of the initial normal-breathing exercise and the
deep-breathing exercises from revised PortaCount[supreg] QNFT protocol
2 results in a conservative fit test. Dr. Crutchfield cited a number of
studies to support the proposition that the normal-breathing exercise
fit factor is among the lowest of the exercise fit factors, and that
its elimination would produce a higher, less conservative, overall fit
factor.
The Agency believes that researchers cannot evaluate validly the
effects of shortened exercises on respirator fit using subsets of
sampling data from a standard, full-length respirator fit test because
respirator fit may vary during an exercise. Additionally, OSHA believes
that Dr. Crutchfield raised important questions about the removal of
the normal-breathing and deep-breathing exercises that the Study's
limited data presentation does not fully rebut (see item D.2 of this
section).
The Department of Defense (DOD) commented that the Study design was
appropriate, but deviated from the ANSI protocol in that user seal
checks were not conducted (Ex. OSHA-2007-0007-0021.1). DOD stated:

The DOD views user seal checks to be a necessary element in any
respirator program and user seal checks should have been conducted
even if the test subject was identified as testing a poorly fitting
facepiece. User seal checks are required for performing fit-testing
by the OSHA Respirator Standard and by ANSI Z88.10-2001.

In response to this comment, OSHA notes that some study
participants used respirators that were too small or too large to
ensure that a number of poor respirator fits occurred. This procedure
induced poor facepiece-to-face seals, which caused the respirators to
leak. These leaks, in turn, provided data for use in determining how
effectively the revised PortaCount[supreg] QNFT protocols detected such
leaks. Therefore, although the Study did not present a rationale for
excluding seal checks, OSHA concludes that the Study needed leakage
data to determine the efficacy of the revised PortaCount[supreg] QNFT
protocols, which justified the omission.
Ching-tsen Bien (Ex. OSHA-2007-0007-0017.1) and Larry Janssen (Ex.
OSHA-2007-0007-0018.1) recommended that the authors of the Study
validate the revised PortaCount[supreg] QNFT protocols using a
generated-aerosol procedure in a test chamber. In this regard, Mr. Bien
commented:

The PortaCount[supreg] is a field instrument but not a research
instrument. For a validation study, the testing should be performed
inside a test chamber with a uniform and constant stable
concentration. The fit test results should be reported continuously,
rather than at selected time intervals. The PortaCount[supreg]
utilizes the ambient air as a test agent and the test results may be
affected by a change in air particle concentration.

Similarly, Clifton D. Crutchfield wrote (Ex. OSHA-2007-0007-0019.1)
that the use of the standard OSHA PortaCount[supreg] protocol as a
reference measure for new protocols ``presents a real quandary because
the sensitivity of the standard PortaCount protocol has itself not been
established.''
In response to these criticisms regarding the use of the standard
PortaCount[supreg] protocol as a reference measure, OSHA notes that
none of the existing fit-testing procedures, including generated-
aerosol methods, has been validated as a reference tool. In the absence
of a fully validated reference test, OSHA requires that new QNFT
protocols be evaluated against accepted QNFT methods. Thus, the Agency
allows QNFT protocols to be tested against ambient-aerosol protocols,
and ANSI Z88.10-2001 provides guidelines for evaluating new QNFT
protocols against any of the currently accepted QNFT procedures.
In summary, the commenters raised a number of valid concerns
regarding the methodology used in the Study. The Agency concludes that
the Study did not implement accepted experimental design practices to
the extent necessary to include the revised PortaCount[supreg] QNFT
protocols to Appendix A of the Respiratory Protection Standard.
2. Were the results of the studies described in this article properly,
fully, and fairly presented and interpreted?
NIOSH (Ex. OSHA-2007-0007-0016.1), James S. Johnson (Ex. OSHA-2007-
0007-0023.1), and Ching-tsen Bien (Ex. OSHA-2007-0007-0017.1)
criticized the failure to differentiate clearly the results for half-
mask and full-facepiece respirators. Mr. Bien stated:

The purpose of this study should be the comparison between the
revised PortaCount and the regular PortaCount methods. Both half-
mask and full-facepiece elastomeric respirators were selected for
this study. There should be two sets of data, one for each type of
mask, since the passing criterion is different for each type of
respirator. For each type of respirator, there should be two sets of
data; one set for the 60-second exercise, and one set for shorter
time or less exercises. Only one set of data is presented in the
paper and it combines the half-mask and full-facepiece data.

Similarly, James S. Johnson commented:

Half-mask and full face piece respirators are normally
considered two different types of air purifying respirators with
different fitting, design and performance properties. The
combination of these types of respirators into one set of data for
analysis and conclusions doesn't appropriately recognize their
performance differences.

OSHA believes that the Study failed to properly differentiate the
fit-testing results for half-mask and full-facepiece respirators.
Although OSHA previously approved the controlled negative pressure
(CNP) REDON fit-testing protocol based in part on a study that mixed
fit-testing results for half-mask and full-facepiece respirators (Ex.
2-2, Docket No. H-049C), the Agency finds the largely undifferentiated
results from the revised PortaCount[supreg] QNFT protocols to be more
problematic than the CNP REDON results. In the final rule on the CNP
REDON protocol, OSHA explained that ``[w]hile the Agency agrees that *
* * combining results for different respirator types may lead to
inconsistent results with large statistical variations, the peer-
reviewed studies showed that large statistical variations did not
occur.'' In contrast to the studies submitted for the CNP REDON
protocol, the study for the revised PortaCount[supreg] QNFT protocols
does not present results in sufficient detail to allow OSHA to examine
the variation in fit-testing results. Moreover, while two peer-

[[Page 4328]]

reviewed journal articles supported the CNP REDON protocol, the article
describing the Study is the sole publication supporting the revised
PortaCount[supreg] QNFT protocols. Therefore, OSHA believes that the
failure to differentiate fit-testing results for half-mask and full-
facepiece respirators obscures interpretation of the Study's statistics
because (1) evaluating the variability of the test results for this
study is impossible, and (2) the limited data presentation does not
support the revised PortaCount[supreg] QNFT protocols.
NIOSH (Ex. OSHA-2007-0007-0016.1) and Ching-tsen Bien (Ex. OSHA-
2007-0007-0017.1) noted that the Study failed to present clearly a
number of important data. For both protocols, NIOSH noted that the
Study provided ``[i]nsufficient detail and data concerning application
of the recommended ANSI acceptance criteria for the number of tests
performed and the distribution of good and poor fitting respirators in
the test population.'' With regard to revised PortaCount[supreg]
protocol 2, NIOSH cited a ``lack of detail, data and discussion of
performance in relation to the unique acceptable fit factors of 200 for
a half-mask and 1000 for a full facepiece respirator.'' Mr. Bien noted
that the Study did not follow the ANSI Z88.10-2001 recommendation that
investigators present a table containing information on respirator
make, model, size, individuals tested, and the results of the new test
and fit factors for the reference test. Mr. Bien also observed that
``except for Figure 1 in the paper, the test data is not presented.''
OSHA agrees that the Study did not present a sufficient level of
detail regarding individual fit-testing results, the types of
respirators selected, and the distribution of respirator fits in the
test population. Although the Study provided a histogram showing the
distribution of RFFs, these data are difficult to interpret in the
absence of information about which fit factors derive from half-mask
versus full-facepiece respirators.
3. Will the proposed protocols generate reproducible fit-testing
results?
Several commenters, including Ching-tsen Bien (Ex. OSHA-2007-0007-
0017.1), Clifton D. Crutchfield (Ex. OSHA-2007-0007-0019.1), and NIOSH
(Ex. OSHA-2007-0007-0016.1) noted that the data presented in the Study
do not facilitate an evaluation of reproducibility. Mr. Bien stated,
``[s]ince the individual test data is not presented in the paper, there
is no information to determine the data reproducibility.'' While
similarly noting the absence of data describing the variability of fit-
testing results in the Study, Dr. Crutchfield drew OSHA's attention to
the results of a study by Sreenath et al. (2001). Examining the results
of this study, Dr. Crutchfield noted that data from 10-second mask
samples had a larger standard deviation than the data from 60-second
mask samples.
NIOSH (Ex. OSHA-2007-0007-0016.1) also questioned the
reproducibility of the fit-testing results from the revised
PortaCount[supreg] QNFT protocols. Because revised PortaCount[supreg]
QNFT protocol 1 did not meet the ANSI Z88.10-2001 acceptance criteria
for sensitivity and predictive value of a pass, NIOSH concluded that
protocol 1 would have ``a diminished likelihood of achieving
reproducible fit-testing results when compared to the established
method.'' With regard to revised PortaCount[supreg] QNFT protocol 2,
NIOSH stated:

The results of the Protocol 2 evaluation are insufficient to
conclude that reproducible fit-testing results could be achieved
using this protocol. The article does not describe whether each
paired set represents the fit factors for a half mask or full
facepiece respirator. It appears that some full facepiece respirator
paired sets failed to meet the acceptable fit factor at 500. Thus,
they were grouped with paired sets of data and treated as meeting
the acceptable fit factor of 100, normally used for half mask
respirators. These paired sets were also included in the data for
failing to meet the required fit factor of 500, normally used for
full facepiece respirators.

OSHA believes that NIOSH's comments regarding test sensitivity and
the predictive value of a pass address the accuracy, rather than the
reproducibility, of the fit-test results. An evaluation of
reproducibility would require information concerning the variability of
the fit-testing results, which, as noted above, the Study did not
provide. However, OSHA agrees that the reproducibility of the data is
further obscured by the failure to differentiate clearly the fit-
testing results for both half-mask and full-facepiece respirators.
James S. Johnson wrote (Ex. OSHA-2007-0007-0023.1) that
``additional experimental work is needed to determine if the reported
results are reproducible when obtained from a representative set of
workers following the required manufacturer user instructions and using
a user seal check.'' While additional information about the
characteristics of the Study participants would allow OSHA to evaluate
whether these participants were representative of employees who use the
respirators, the Agency finds no evidence that the participants were
unrepresentative of the employee population. In addition, while strict
compliance with manufacturer instructions may improve fit-test
performance, the commenter provided no data indicating that poor
compliance with these instructions biased the Study results. Finally,
as discussed above (see item D.1 of this section), OSHA determined that
omitting seal checks was necessary to determine the efficacy of the
revised PortaCount[supreg] QNFT protocols.
Jeff Weed (Ex. OSHA-2007-0007-0014.1) expressed confidence in the
reproducibility of the test results from revised PortaCount[supreg]
QNFT protocols 1 and 2, and described the revised exercises as ``long
enough to ensure that face leaks are accurately detected.'' Mr. Weed
also asserted that the Study ``proved that shortened measurement yields
the same result as the longer measurement.'' However, OSHA believes
that Mr. Weed failed to address the issue of the reproducibility of the
fit-testing results because he did not adequately explain the
deficiencies in the data presentation identified elsewhere in this
section.
Several commenters, including DOD (Ex. OSHA 2007-0007-0021.1) and
James Johnson (Ex. OSHA-2007-0007-0023.1) recommended that OSHA require
additional validation testing before accepting revised
PortaCount[supreg] QNFT protocol 1 or 2, implying that the results were
not reproducible.
In summary, the Study did not establish the reproducibility of test
results for the revised PortaCount[supreg] QNFT protocols. The Study
did not present test results or statistics describing the variability
of the results of protocols 1 and 2. Moreover, because of the
previously discussed flaws in the data analysis, a meaningful
evaluation of the reproducibility of the results is not possible.
4. Will the proposed protocols reliably identify respirators with
unacceptable fit as effectively as the quantitative fit-testing
protocols, including the standard PortaCount[supreg] QNFT protocol,
already listed in Part I.C.3 of Appendix A of the Respiratory
Protection Standard?
Jeff Weed (Ex. OSHA-2007-0007-0014.1) asserted that the revised
PortaCount[supreg] QNFT protocols would perform as well as any of the
QNFT methods, and that the differences between the reference methods
and the proposed protocols ``can be easily explained in terms of the
limited number of test subjects and instrument variability.'' OSHA
believes that any fit-testing protocol based on a study that involved
significant instrument

[[Page 4329]]

variability and small sample size, as well as a flawed data analysis
and an inadequate data presentation, is of questionable validity and
utility.
In the view of NIOSH (Ex. OSHA-2007-0007-0016.1), DOD (Ex. OSHA-
2007-0007-0021.1), and Clifton D. Crutchfield (Ex. OSHA-2007-0007-
0019.1), the failure of revised PortaCount[supreg] QNFT protocol 1 to
meet the ANSI Z88.10-2001 criteria demonstrates that this protocol will
not identify respirators with unacceptable fit as effectively as the
accepted QNFT protocols. Because revised PortaCount[supreg] QNFT
protocol 2 met the ANSI Z88.10-2001 criteria, DOD concluded that
protocol 2 would identify respirators with unacceptable fit as reliably
as accepted QNFT methods. In contrast to this view, NIOSH found that
``[u]ncertain data treatment * * * prevent[s] answering the question of
whether revised PortaCount[supreg] QNFT protocol 2 will reliably
identify respirators with unacceptable fit as effectively as [accepted
QNFT] protocols,'' and ``[t]he report of the test-sensitivity [of this
protocol] having surpassed ANSI criteria does not resolve
uncertainty.'' Similarly, Ching-tsen Bien (Ex. OSHA-2007-0007-0017.1)
wrote that ``[s]ince the individual test data is not available, it is
not possible to determine whether the proposed test protocols would
reliably identify respirators with unacceptable fit as effectively as
the regular quantitative fit-testing protocols.''
OSHA agrees with NIOSH and Mr. Bien that the flawed data analysis
and inadequate presentation of fit-testing results (see item D.2 of
this section) prevents the Agency from thoroughly evaluating whether
either of the proposed protocols would reliably identify respirators
with unacceptable fit as effectively as accepted quantitative fit-
testing protocols. However, the test-sensitivity value reported for
revised PortaCount[supreg] QNFT protocol 1 indicates that this protocol
would not identify respirators with unacceptable fit as reliably as
accepted quantitative fit-testing protocols.
Clifton D. Crutchfield questioned whether doubling the RFFs for
revised PortaCount[supreg] QNFT protocol 2 is sufficient to compensate
for the protocol's potential deficiency of test sensitivity, and
asserted that Sreenath et al. (2001) multiplied the conventional RFFs
by fourteen to ensure the sensitivity of a new protocol that relied on
a 20-second in-mask sampling period (Ex. OSHA-2007-0007-0019.1). OSHA
agrees that the Study did not discuss adequately the implications of
doubling the RFFs. As noted in section A above, increasing the
sensitivity of a protocol by raising the RFFs may increase beta (false-
negative) error, which would increase the number of repeated tests and,
consequently, total testing time. Although the Study reported
sensitivity and specificity values for revised PortaCount[supreg] QNFT
protocol 2 that exceeded the ANSI criteria, the Study's flawed data
analysis and inadequate data presentation bring into question the
validity of these values.
In conclusion, OSHA believes that the Study did not analyze or
present the fit-testing results in a manner that demonstrates that the
proposed protocols would reliably identify respirators with
unacceptable fit as effectively as accepted quantitative fit-testing
protocols.
5. Is the test-sensitivity value of 0.91 obtained for half masks by
revised PortaCount[supreg] QNFT protocol 1 acceptable in view of the
test-sensitivity value of 0.95 required by ANSI Z88.10-2001; if not,
would it be appropriate for OSHA to limit application of revised
PortaCount[supreg] QNFT protocol 1 to full-facepiece respirators? \4\
---------------------------------------------------------------------------

\4\ See discussion of grouping fit-testing results for half-mask
and full-facepiece respirators under section II.A (``Introduction'')
of this notice. Accordingly, commenters generally responded to this
issue as though the fit tests comprising RFFs < 100 and > 100
consisted of fit tests for both half-mask and full-facepiece
respirators, not just fit tests for half-mask respirators.
---------------------------------------------------------------------------

Many commenters, including Clifton D. Crutchfield (Ex. OSHA-2007-
0007-0019.1), David Spelce (Ex. OSHA-2007-0007-0013.1), NIOSH (Ex.
OSHA-2007-0007-0016.1), James Johnson (Ex. OSHA-2007-0007-0023.1), DOD
(Ex. OSHA-2007-0007-0021.1), AFL-CIO (Ex. OSHA-2007-0007-0015), and
Ching-tsen Bien (Ex. OSHA-2007-0007-0017.1) expressed the opinion that
the test-sensitivity value of 0.91 is unacceptable, and that it would
be inappropriate to accept revised PortaCount[supreg] QNFT protocol 1
for use with half-mask or full-facepiece respirators. Dr. Crutchfield
noted that ``[t]he test-sensitivity value of 0.95 was the only test
statistic designated by ANSI in its Fit Test Methods standard as a
criterion value that `shall' be met when accepting new fit test
methods.'' NIOSH stated:
The results reported in the peer-reviewed journal article for
either reference fit factor (RFF) of protocol 1 do not meet the full
criteria of the Annex A2 evaluation standard against which they are
to be judged. As such, it would not be appropriate to accept the
application of revised PortaCount[supreg] QNFT protocol 1 to either
half-mask or full-facepiece respirators.

Larry Janssen (Ex. OSHA-2007-0007-0018.1) and Jeff Weed (Ex. OSHA-
2007-0007-0014.1) commented that the test-sensitivity value of 0.91 is
acceptable despite the ANSI criterion sensitivity value of 0.95. In
explaining this position, Mr. Janssen stated that instrument
variability is approximately 5% of the true value, and
asserted that the variability of facepiece-to-face seal leakage in the
Study would increase this variability by at least another 5%. Assuming
an overall variability of at least 10%, he questioned whether it is
meaningful to calculate sensitivity values to two decimal places. In
addition, Mr. Janssen cited a study (Janssen, L.L., et al., 2002) that
found that none of the three currently accepted quantitative fit-
testing protocols met the ANSI sensitivity criterion of 0.95, noting
that ``it would be inappropriate for OSHA to hold new fit tests to a
higher standard than the currently accepted fit tests can meet.''
Recognizing that the variability described by Mr. Janssen introduces
error into fit-testing measurement, OSHA does not believe that
increasing this error further by adopting a sensitivity value of 0.91
would improve employee protection.
OSHA believes that the ANSI Z88.10-2001 standard represents the
consensus of the industrial-hygiene community regarding the criteria to
use in assessing fit-testing protocols. The majority of the comments to
the proposal indicated that the industrial-hygiene community generally
supports using the ANSI standard for this purpose. Thus, despite Mr.
Janssen's assertion of an inevitable 10% variability in any fit-testing
protocol, and regardless of whether the accepted fit-testing protocols
achieve the ANSI criteria, OSHA believes that the ANSI criteria are
meaningful measures of performance for new fit-testing protocols,
although it does not treat the ANSI criterion for test sensitivity as
an absolute requirement for new fit-testing protocols. In considering
the test-sensitivity value for the Abbreviated Bitrex Qualitative Fit-
Testing (ABQLFT) protocol, OSHA projected the annual number of
employees with improperly fitting respirators who would pass the
proposed ABQLFT protocol, which achieved a test-sensitivity value of
0.92, and compared this estimate with the projected number of false-
positives expected if the ABQLT protocol achieved the ANSI sensitivity
criterion of 0.95. OSHA deemed the excess number of false positives at
the test-sensitivity of 0.92 to be unacceptable. (See 74 FR 30250,
30254.) However, OSHA could not make this

[[Page 4330]]

determination for revised PortaCount[supreg] QNFT Protocol 1 because
the Study did not present adequate fit-testing results to do so.
Nonetheless, the frequency of ambient-aerosol fit testing (see NIOSH-
BLS survey, Ex. 6-3, Docket No. H-049C) indicates that, compared to a
fit-testing protocol having a test sensitivity at the ANSI criterion of
0.95, substantially more employees would receive false-positive fit-
testing results using revised PortaCount[supreg] QNFT protocol 1. Thus,
OSHA concludes that the test-sensitivity value of 0.91 achieved by
revised PortaCount[supreg] QNFT protocol 1 is too low to include this
protocol in Appendix A of its final Respiratory Protection Standard.
Jeff Weed recommended that the high test-sensitivity value obtained
by revised PortaCount[supreg] QNFT protocol 1 at the RFF of 500
justifies the protocol's acceptance at the RFF of 100 (Ex. OSHA-2007-
0007-0014.1). In this regard, Mr. Weed commented, ``The fact that the
testing near 500 had better results than the near 100 results is
indicative of the inherent limitations of this type of study including
variability of face seal leaks, the instrumentation, and the
statistical sample size (number of people).'' Mr. Weed also compared
revised PortaCount[supreg] QNFT protocol 1 to the previously proposed
ABQLFT protocol, which also failed to meet the ANSI criterion for test
specificity. Mr. Weed stated, ``Any decision by OSHA to reject a
protocol based on the ANSI criteria must be applied equally.''
OSHA does not believe that the test-sensitivity value that the
Study reported at the RFF of 500 justifies acceptance of revised
PortaCount[supreg] QNFT protocol 1. Mr. Weed cites variability due to
face leaks, instrumentation, and small sample size as possible
explanations for an erroneous test-sensitivity result at the RFF of
100. However, OSHA believes that the inconsistency of the test-
sensitivity values at RFFs of 100 and 500 raises doubt about both of
these values. In addition, as discussed above (see item D.4 of this
section), OSHA concluded that instrument variability or a small sample
size does not justify acceptance of a protocol with flawed data
analyses and inadequate data presentation, particularly when OSHA
determined that the ANSI criterion for test sensitivity, although not
an absolute requirement for new fit-testing protocols, is reasonable.
Finally, OSHA does not treat the ANSI criteria for test sensitivity as
absolute requirements for new fit-testing protocols. Therefore, OSHA
would not base a decision to reject a protocol with inadequate test-
sensitivity solely on the ANSI criteria. In conclusion, OSHA finds that
including revised PortaCount[supreg] QNFT protocol 1 in Appendix A of
its final Respiratory Protection Standard is unwarranted because this
protocol would allow a substantially larger number of employees to use
improperly fitting respirators than would be the case for a protocol
that achieves the 0.95 test-sensitivity criterion specified by ANSI
Z88.10-2001.
6. The Study evaluating the proposed protocols involved only
elastomeric half-mask and full-facepiece respirators. Accordingly, is
it appropriate to apply the results of the Study to other types of
respirators (e.g., filtering-facepiece respirators)?
Jeff Weed (Ex. OSHA-2007-0007-0014.1) and Larry Janssen (Ex. OSHA-
2007-0007-0018.1) provided comments in favor of applying the Study
results to untested respirator types. In support of this view, Mr.
Janssen wrote, ``There are no data that suggest a measured amount of
faceseal leakage for a Class 100 FFR would be somehow different that
the same amount of leakage measured on elastomeric facepieces with
Class 100 filters.'' Elaborating on this point, Mr. Weed stated:

Leaks are leaks. An instrument used for QNFT does not ``know''
what type of respirator is attached to the end of the sample tube.
The instrument cannot know the path taken by a particle found in the
breathing zone of a respirator. Particles are either present, or not
present. As far as the instrument is concerned, there is no
difference between leaks in an elastomeric face seal vs. the seal of
a filtering-facepiece. The McKay study was conducted with a target
fit factors of 100 and 500, which qualifies the application of the
resulting protocols for fit-testing any respirator at those values.

NIOSH (Ex. OSHA-2007-0007-0016.1), DOD (Ex. OSHA-2007-0007-0021.1),
AFL-CIO (Ex. OSHA-2007-0007-0015), and Ching-tsen Bien (Ex. OSHA-2007-
0007-0017.1) discouraged application of the Study results to respirator
types not tested in the Study. NIOSH stated that it is ``unaware of any
studies or data demonstrating that all respirator types perform
similarly when being subjected to a fit test,'' and, ``It is
inappropriate to conclude that a test result applies to more than just
those types of respirators that were tested.'' Similarly, DOD stated:

[I]t is not appropriate to apply the study results to other
types of respirators. * * * There are many types and styles of NIOSH
approved filtering-facepiece respirators. There is also ongoing
controversy about fit testing, efficacy and actual protection
afforded by filtering facepiece respirators given the variation in
styles within the class. * * * Any change to current QNFT protocols
that allow filtering facepiece respirators (as a class) to be
included should be based on actual fit testing data per ANSI Z88.10-
2001 or the current edition.

Larry Janssen asserted that Class 100 filtering-facepiece
respirators are the only filtering-facepiece respirators that would be
appropriate for fit-testing using the revised PortaCount[supreg] QNFT
protocols (Ex. OSHA-2007-0007-0018.1). Clifton D. Crutchfield
questioned whether any filtering-facepiece respirators can be
effectively fit tested with the PortaCount[supreg] N-95 Companion using
the proposed protocols (Ex. OSHA-2007-0007-0019.1). Dr. Crutchfield
stated, ``The [N-95] Companion can * * * report fit factors only up to
200. This obviously precludes the use of Revised PortaCount[supreg]
Protocol 2.'' Dr. Crutchfield also noted that revised
PortaCount[supreg] QNFT protocol 1 has an in-mask sampling time of 10
seconds, which ``allows sampling only about 2 breaths per exercise in
order to determine an in-mask concentration for that exercise.'' In the
absence of data demonstrating that the PortaCount[supreg] N-95
Companion can effectively measure respirator leakage in ten seconds,
Dr. Crutchfield remarked that ``allowing such fit-testing to occur
would be neither justified nor prudent.''
OSHA does not believe that it is appropriate to apply the fit-
testing results to types of respirators not tested in the Study. While
Mr. Janssen emphasizes the absence of data demonstrating that fit-
testing protocols perform differently on different respirator types,
OSHA views this lack of information on the consistency of fit-test
performance as a reason to avoid generalizing from the results of the
Study. Accordingly, OSHA believes that it would be prudent to validate
new fit-test protocols using filtering-facepiece respirators because
filtering-facepiece respirators are the most commonly used respirator.
(See Table 30, NIOSH-BLS survey, Ex. 6-3, Docket No. H-049C.)
However, as Dr. Crutchfield and Mr. Janssen note, a question
remains as to whether filtering-facepiece respirators can be
effectively fit tested using the revised PortaCount[supreg] QNFT
protocols. In view of the considerable uncertainty as to the
consistency of fit-test protocol performance on different respirator
types, OSHA concludes that the Study did not establish that the revised
PortaCount[supreg] QNFT protocols will accurately determine fit for N95
filtering-facepiece respirators.

E. Conclusions

Based on a complete and thorough review of the rulemaking record,
OSHA concludes that:

[[Page 4331]]

1. The Study was not conducted according to accepted experimental
design practices and principles.
2. The Study did not properly or fully describe the fit-testing
results.
3. The Study did not establish the reproducibility of the results
generated by the revised PortaCount[supreg] QNFT protocols.
4. The Study did not demonstrate that the revised
PortaCount[supreg] QNFT protocols will identify respirators with
unacceptable fit as effectively as the quantitative fit-testing
protocols already listed in Part I.C.3 of Appendix A of OSHA's
Respiratory Protection Standard.
5. The reported test-sensitivity value of 0.91 indicates that
revised PortaCount[supreg] QNFT protocol 1 would allow a substantial
number of employees to pass fit tests with improperly fitting
respirators compared to a protocol that achieves the 0.95 sensitivity
value that ANSI Z88.10-2001 lists as a criterion measure for new fit-
testing protocols.
6. The Study did not demonstrate that the revised
PortaCount[supreg] QNFT protocols will accurately determine fit for
filtering-facepiece respirators.
Additional validation testing of, or revisions to, the revised
PortaCount[supreg] QNFT protocols may provide new data that demonstrate
the accuracy and reproducibility of the fit-testing results generated
by these protocols. OSHA would evaluate any new data and supporting
documentation received, and, if appropriate, would submit it to the
public for notice and comment. If the revised protocols are to apply to
filtering-facepiece respirators, then the resubmission must include
appropriate fit-testing results for these respirators.

List of Subjects in 29 CFR Part 1910

Fit testing, Hazardous substances, Health, Occupational safety and
health, Respirators, Toxic substances.

Authority and Signature

David Michaels, PhD, MPH, Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, 200
Constitution Avenue, NW., Washington, DC 20210, directed the
preparation of this notice. Accordingly, the Agency issues this notice
under the following authorities: Section 4, 6(b), 8(c), and 8(g) of the
Occupational Safety and Health Act of 1970 (29 U.S.C. 653, 655 657);
Section 3704 of the Contract Work Hours and Safety Standards Act (40
U.S.C. 3701 et seq.); Section 41 of the Longshore and Harbor Worker's
Compensation Act (33 U.S.C. 941); Secretary of Labor's Order No. 5-2007
(72 FR 31160); and 29 CFR part 1911.

Signed at Washington, DC, on January 22, 2010.
David Michaels,
Assistant Secretary of Labor for Occupational Safety and Health.
[FR Doc. 2010-1656 Filed 1-26-10; 8:45 am]
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