[Code of Federal Regulations]
[Title 49, Volume 6]
[Revised as of October 1, 2006]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR571.202a]
[Page 531-542]
TITLE 49--TRANSPORTATION
CHAPTER V--NATIONAL HIGHWAY TRAFFIC
SAFETY ADMINISTRATION, DEPARTMENT
OF TRANSPORTATION
PART 571_FEDERAL MOTOR VEHICLE SAFETY STANDARDS--Table of Contents
Subpart B_Federal Motor Vehicle Safety Standards
Sec. 571.202a Standard No. 202a; Head restraints; Mandatory applicability begins on September 1, 2008.
S1. Purpose and scope. This standard specifies requirements for head
restraints to reduce the frequency and severity of neck injury in rear-
end and other collisions.
S2. Application & incorporation by reference.
S2.1 Application. This standard applies to passenger cars, and to
multipurpose passenger vehicles, trucks and buses with a GVWR of 4,536
kg or less, manufactured on or after September 1, 2008. Mandatory
applicability begins on September 1, 2008. Until September 1, 2008,
manufacturers may comply with the standard in this Sec. 571.202a, with
the standard in Sec. 571.202, or with the European regulations
referenced in S4.3(a) of Sec. 571.202.
S2.2 Incorporation by reference.
(a) Society of Automotive Engineers (SAE) Recommended Practice J211/
1 rev. Mar 95, ``Instrumentation for Impact Test--Part 1--Electronic
Instrumentation,'' SAE J211/1 (rev. Mar 95) is incorporated by reference
in S5.2.5(b), S5.3.8, S5.3.9, and 5.3.10 of this section. The Director
of the Federal Register has approved the incorporation by reference of
this material in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. A
copy of SAE J211/1 (rev. Mar 95) may be obtained from SAE at the Society
of Automotive Engineers, Inc., 400 Commonwealth Drive, Warrendale, PA
15096. A copy of SAE J211/1 (rev. Mar 95) may be inspected at NHTSA's
Technical Information Services, 400 Seventh Street, SW., Plaza Level,
Room 403, Washington, DC, or at the National Archives and Records
Administration (NARA). For information on the availability of this
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/
federal--register/code--of--federal--regulations/ibr--locations.html.
(b) Society of Automotive Engineers (SAE) Standard J826 ``Devices
for Use in Defining and Measuring Vehicle Seating Accommodation,'' SAE
J826 (rev. Jul 95) is incorporated by reference in S3, S5, S5.1, S5.1.1,
S5.2, S5.2.1, S5.2.2, and S5.2.7 of this section. The Director of the
Federal Register has approved the incorporation by reference of this
material in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. A copy of
SAE J826 (rev. Jul 95) may be obtained from SAE at the Society of
Automotive Engineers, Inc., 400 Commonwealth Drive, Warrendale, PA
15096. A copy of SAE J826 (rev. Jul 95) may be inspected at NHTSA's
Technical Information Services, 400 Seventh Street, SW., Plaza Level,
Room 403, Washington, DC or at the National Archives and Records
Administration (NARA). For information on the availability of this
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/
federal--register/code--of--federal--regulations/ibr--locations.html.
S3. Definitions.
Backset means the minimum horizontal distance between the rear of a
representation of the head of a seated 50th percentile male occupant and
the head restraint, as measured by the head restraint measurement
device.
Head restraint means a device that limits rearward displacement of a
seated occupant's head relative to the occupant's torso.
Head restraint measurement device (HRMD) means the Society of
Automotive Engineers (SAE) (rev. Jul 95) J826 three-dimensional manikin
with a head form attached, representing the head position of a seated
50th percentile male, with sliding scale at the back of the head for the
purpose of measuring backset. The head form is designed by and available
from the ICBC, 151 West Esplanade, North Vancouver, BC V7M 3H9, Canada
(www.icbc.com).
Height means, when used in reference to a head restraint, the
distance from the H-point, measured parallel to the torso reference line
defined by the three dimensional SAE J826 (rev. Jul 95) manikin, to a
plane normal to the torso reference line.
[[Page 532]]
Intended for occupant use means, when used in reference to the
adjustment of a seat, positions other than that intended solely for the
purpose of allowing ease of ingress and egress of occupants and access
to cargo storage areas of a vehicle.
Rear head restraint means, at any rear outboard designated seating
position, a rear seat back, or any independently adjustable seat
component attached to or adjacent to a seat back, that has a height
equal to or greater than 700 mm, in any position of backset and height
adjustment, as measured in accordance with S5.1.1.
Top of the head restraint means the point on the head restraint with
the greatest height.
S4. Requirements. Except as provided in S4.4 and S.4.2.1(b)(2) of
this section, each vehicle must comply with S4.1 of this section with
the seat adjusted as intended for occupant use. Whenever a range of
measurements is specified, the head restraint must meet the requirement
at any position of adjustment within the specified range.
S4.1 Performance levels. In each vehicle other than a school bus, a
head restraint that conforms to either S4.2 or S4.3 of this section must
be provided at each front outboard designated seating position. In each
vehicle manufactured after September 1, 2010 and equipped with rear
outboard head restraints, the rear head restraint must conform to either
S4.2 or S4.3 of this section. In each school bus, a head restraint that
conforms to either S4.2 or S4.3 of this section must be provided for the
driver's seating position. At each designated seating position incapable
of seating a 50th percentile male Hybrid III test dummy specified in 49
CFR part 572, subpart E, the applicable head restraint must conform to
S4.2 of this section.
S4.2 Dimensional and static performance. Each head restraint located
in the front outboard designated seating position and each head
restraint located in the rear outboard designated seating position must
conform to paragraphs S4.2.1 through S4.2.7 of this section:
S4.2.1 Minimum height.
(a) Front outboard designated seating positions. (1) Except as
provided in S4.2.1(a)(2) of this section, when measured in accordance
with S5.2.1(a)(1) of this section, the top of a head restraint located
in a front outboard designated seating position must have a height not
less than 800 mm in at least one position of adjustment.
(2) Exception. The requirements of S4.2.1(a)(1) do not apply if the
vehicle roofline physically prevents a head restraint, located in the
front outboard designated seating position, from attaining the required
height. In those instances in which this head restraint cannot attain
the required height, when measured in accordance with S5.2.1(a)(2), the
maximum vertical distance between the top of the head restraint and the
roofline must not exceed 25 mm. Notwithstanding this exception, when
measured in accordance with S5.2.1(a)(2), the top of a head restraint
located in a front outboard designated seating position must have a
height not less than 700 mm in the lowest position of adjustment.
(b) All outboard designated seating positions equipped with head
restraints. (1) Except as provided in S4.2.1(b)(2) of this section, when
measured in accordance with S5.2.1(b)(1) of this section, the top of a
head restraint located in an outboard designated seating position must
have a height not less than 750 mm in any position of adjustment.
(2) Exception. The requirements of S4.2.1(b)(1) do not apply if the
vehicle roofline or backlight physically prevent a head restraint,
located in the rear outboard designated seating position, from attaining
the required height. In those instances in which this head restraint
cannot attain the required height, when measured in accordance with
S5.2.1(b)(2), the maximum vertical distance between the top of the head
restraint and the roofline or the backlight must not exceed 25 mm.
S4.2.2 Width. When measured in accordance with S5.2.2 of this
section, 65 3 mm below the top of the head
restraint, the lateral width of a head restraint must be not less than
170 mm, except the lateral width of the head restraint for front
outboard designated seating positions in a vehicle with a front center
designated seating position, must be not less than 254 mm.
[[Page 533]]
S4.2.3 Front Outboard Designated Seating Position Backset. When
measured in accordance with S5.2.3 of this section, the backset must not
be more than 55 mm, when the seat is adjusted in accordance with S5.1.
For adjustable restraints, the requirements of this section must be met
with the top of the head restraint in any height position of adjustment
between 750 mm and 800 mm, inclusive. If the top of the head restraint,
in its lowest position of adjustment, is above 800 mm, the requirements
of this section must be met at that position. If the head restraint
position is independent of the seat back inclination position, the head
restraint must not be adjusted such that backset is more than 55 mm when
the seat back inclination is positioned closer to vertical than the
position specified in S5.1.
S4.2.4 Gaps within head restraint and between the head restraint and
seat. When measured in accordance with S5.2.4 of this section using the
head form specified in that paragraph, there must not be any gap greater
than 60 mm within or between the anterior surface of the head restraint
and anterior surface of the seat, with the head restraint adjusted to
its lowest height position and any backset position.
S4.2.5 Energy absorption. When the anterior surface of the head
restraint is impacted in accordance with S5.2.5 of this section by the
head form specified in that paragraph at any velocity up to and
including 24.1 km/h, the deceleration of the head form must not exceed
785 m/s\2\ (80 g) continuously for more than 3 milliseconds.
S4.2.6 Height retention. When tested in accordance with S5.2.6 of
this section, the cylindrical test device specified in S5.2.6(b) must
return to within 13 mm of its initial reference position after
application of at least a 500 N load and subsequent reduction of the
load to 50 N 1 N. During application of the
initial 50 N reference load, as specified in S5.2.6(b)(2) of this
section, the cylindrical test device must not move downward more than 25
mm.
S4.2.7 Backset retention, displacement, and strength.
(a) Backset retention and displacement. When tested in accordance
with S5.2.7 of this section, the described head form must:
(1) Not be displaced more than 25 mm during the application of the
initial reference moment of 37 0.7 Nm;
(2) Not be displaced more than 102 mm perpendicularly and posterior
of the displaced extended torso reference line during the application of
a 373 7.5 Nm moment about the H-point; and
(3) Return to within 13 mm of its initial reference position after
the application of a 373 7.5 Nm moment about the
H-point and reduction of the moment to 37 0.7 Nm.
(b) Strength. When the head restraint is tested in accordance with
S5.2.7 (b) of this section with the test device specified in that
paragraph, the load applied to the head restraint must reach 890 N and
remain at 890 N for a period of 5 seconds.
S4.3 Dynamic performance and width. At each forward-facing outboard
designated seating position equipped with a head restraint, the head
restraint adjusted midway between the lowest and the highest position of
adjustment, and at any position of backset adjustment, must conform to
the following:
S4.3.1 Injury criteria. When tested in accordance with S5.3 of this
section, during a forward acceleration of the dynamic test platform
described in S5.3.1, the head restraint must:
(a) Angular rotation. Limit posterior angular rotation between the
head and torso of the 50th percentile male Hybrid III test dummy
specified in 49 CFR Part 572, Subpart E to 12 degrees for the dummy in
all outboard designated seating positions;
(b) Head injury criteria. Limit the maximum HIC15 value
to 500. HIC15 is calculated as follows: for any two points in
time, t1 and t2, during the event which are
separated by not more than a 15 millisecond time interval and where
t1 is less than t2, the head injury criterion
(HIC15) is determined using the resultant head acceleration
at the center of gravity of the dummy head, ar, expressed as
a multiple of g (the acceleration of gravity) and is calculated using
the expression:
[[Page 534]]
[GRAPHIC] [TIFF OMITTED] TR14DE04.150
4.3.2 Width. The head restraint must have the lateral width
specified in S4.2.2 of this section.
S4.4 Folding or retracting rear head restraints. A rear head
restraint may be adjusted to a position at which its height does not
comply with the requirements of S4.2.1 of this section. However, in any
such position, the head restraint must meet either S4.4 (a) or (b) of
this section.
(a) The head restraint must automatically return to a position in
which its minimum height is not less than that specified in S4.2.1(b) of
this section when a test dummy representing a 5th percentile female
Hybrid III test dummy specified in 49 CFR Part 572, Subpart O is
positioned according to S5.4(a); or
(b) The head restraint must, when tested in accordance with S5.4(b)
of this section, be capable of manually rotating forward or rearward by
not less than 60 degrees from any position of adjustment in which its
minimum height is not less than that specified in S4.2.1(b) of this
section.
S4.5 Removability of head restraints. The head restraint must not be
removable without a deliberate action distinct from any act necessary
for adjustment.
S4.6 Compliance option selection. Where manufacturer options are
specified in this section, the manufacturer must select an option by the
time it certifies the vehicle and may not thereafter select a different
option for that vehicle. The manufacturer may select different
compliance options for different designated seating positions to which
the requirements of this section are applicable. Each manufacturer must,
upon request from the National Highway Traffic Safety Administration,
provide information regarding which of the compliance options it has
selected for a particular vehicle or make/model.
S4.7 Information in owner's manual.
S4.7.1 The owner's manual for each vehicle must emphasize that all
occupants, including the driver, should not operate a vehicle or sit in
a vehicle's seat until the head restraints are placed in their proper
positions in order to minimize the risk of severe injury in the event of
a crash.
S4.7.2 The owner's manual for each vehicle must--
(a) Include an accurate description of the vehicle's head restraint
system in an easily understandable format. The owner's manual must
clearly identify which seats are equipped with head restraints;
(b) If the head restraints are removable, the owner's manual must
provide instructions on how to remove the head restraint by a deliberate
action distinct from any act necessary for adjustment, and how to
reinstall head restraints;
(c) Warn that all head restraints must be reinstalled to properly
protect vehicle occupants.
(d) Describe in an easily understandable format the adjustment of
the head restraints and/or seat back to achieve appropriate head
restraint position relative to the occupant's head. This discussion must
include, at a minimum, accurate information on the following topics:
(1) A presentation and explanation of the main components of the
vehicle's head restraints.
(2) The basic requirements for proper head restraint operation,
including an explanation of the actions that may affect the proper
functioning of the head restraints.
(3) The basic requirements for proper positioning of a head
restraint in relation to an occupant's head position, including
information regarding the proper positioning of the center of gravity of
an occupant's head in relation to the head restraint.
S5. Procedures. Demonstrate compliance with S4.2 through S4.4 of
this section with any adjustable lumbar support adjusted to its most
posterior nominal design position. If the seat cushion adjusts
independently of the seat back, position the seat cushion such that the
highest H-point position is achieved with respect to the seat back, as
measured by SAE J826 (rev. Jul 95) manikin, with leg length specified in
S10.4.2.1 of Sec. 571.208.
[[Page 535]]
S5.1 Except as specified in S5.2.3 of this section, if the seat back
is adjustable, it is set at an initial inclination position closest to
25 degrees from the vertical, as measured by SAE J826 manikin (rev. Jul
95). If there is more than one inclination position closest to 25
degrees from vertical, set the seat back inclination to the position
closest to and rearward of 25 degrees.
S5.1.1 Procedure for determining presence of head restraints in rear
outboard seats. Measure the height of the top of a rear seat back or the
top of any independently adjustable seat component attached to or
adjacent to the rear seat back in its highest position of adjustment
using the scale incorporated into the SAE J826 (rev. Jul 95) manikin or
an equivalent scale, which is positioned laterally within 15 mm of the
centerline of the rear seat back or any independently adjustable seat
component attached to or adjacent to the rear seat back.
S5.2 Dimensional and static performance procedures. Demonstrate
compliance with S4.2 of this section in accordance with S5.2.1 through
S5.2.7 of this section. Position the SAE J826 (rev. Jul 95) manikin
according to the seating procedure found in SAE J826 (rev. Jul 95).
S5.2.1 Procedure for height measurement. Demonstrate compliance with
S4.2.1 of this section in accordance with S5.2.1 (a) and (b) of this
section, using the scale incorporated into the SAE J826 (rev. Jul 95)
manikin or an equivalent scale, which is positioned laterally within 15
mm of the head restraint centerline. If the head restraint position is
independent of the seat back inclination position, compliance is
determined at a seat back inclination position closest to 25 degrees
from vertical, and each seat back inclination position less than 25
degrees from vertical.
(a)(1) For head restraints in front outboard designated seating
positions, adjust the top of the head restraint to the highest position
and measure the height.
(2) For head restraints located in the front outboard designated
seating positions that are prevented by the vehicle roofline from
meeting the required height as specified in S4.2.1(a)(1), measure the
clearance between the top of the head restraint and the roofline, with
the seat adjusted to its lowest vertical position intended for occupant
use, by attempting to pass a 25 mm sphere between them. Adjust the top
of the head restraint to the lowest position and measure the height.
(b)(1) For head restraints in all outboard designated seating
positions equipped with head restraints, adjust the top of the head
restraint to the lowest position other than allowed by S4.4 and measure
the height.
(2) For head restraints located in rear outboard designated seating
positions that are prevented by the vehicle roofline or rear backlight
from meeting the required height as specified in S4.2.1(b)(1), measure
the clearance between the top of the head restraint or the seat back and
the roofline or the rear backlight, with the seat adjusted to its lowest
vertical position intended for occupant use, by attempting to pass a 25
mm sphere between them.
S5.2.2 Procedure for width measurement. Demonstrate compliance with
S4.2.2 of this section using calipers to measure the maximum dimension
perpendicular to the vehicle vertical longitudinal plane of the
intersection of the head restraint with a plane that is normal to the
torso reference line of SAE J826 (rev. Jul 95) manikin and 65 3 mm below the top of the head restraint.
S5.2.3 Procedure for backset measurement. Demonstrate compliance
with S4.2.3 of this section using the HRMD positioned laterally within
15 mm of the head restraint centerline. Adjust the front head restraint
so that its top is at any height between and inclusive of 750 mm and 800
mm and its backset is in the maximum position other than allowed by
S4.4. If the lowest position of adjustment is above 800 mm, adjust the
head restraint to that position. If the head restraint position is
independent of the seat back inclination position, compliance is
determined at each seat back inclination position closest to and less
than 25 degrees from vertical.
S5.2.4 Procedures for gap measurement. Demonstrate compliance with
S4.2.4 of this section in accordance with the procedures of S5.2.4 (a)
[[Page 536]]
through (c) of this section, with the head restraint adjusted to its
lowest height position and any backset position.
(a) The area of measurement is anywhere on the anterior surface of
the head restraint or seat with a height greater than 540 mm and within
the following distances from the centerline of the seat--
(1) 127 mm for seats required to have 254 mm minimum head restraint
width; and
(2) 85 mm for seats required to have a 170 mm head restraint width.
(b) Applying a load of no more than 5 N against the area of
measurement specified in S5.2.4(a) of this section, place a 165 2 mm diameter spherical head form against any gap such
that at least two points of contact are made within the area. The
surface roughness of the head form is less than 1.6 [micro]m, root mean
square.
(c) Determine the gap dimension by measuring the vertical straight
line distance between the inner edges of the two furthest contact
points, as shown in Figures 2 and 3 of this section.
S5.2.5 Procedures for energy absorption. Demonstrate compliance with
S4.2.5 of this section in accordance with S5.2.5 (a) through (e) of this
section, with the seat back rigidly fixed and the adjustable head
restraints in any height and backset position of adjustment.
(a) Use an impactor with a semispherical head form and a 165 2 mm diameter and a surface roughness of less than 1.6
[micro]m, root mean square. The head form and associated base have a
combined mass of 6.8 0.05 kg.
(b) Instrument the impactor with an acceleration sensing device
whose output is recorded in a data channel that conforms to the
requirements for a 600 Hz channel class as specified in SAE
Recommended Practice J211/1 (rev. Mar 95). The axis of the acceleration-
sensing device coincides with the geometric center of the head form and
the direction of impact.
(c) Propel the impactor toward the head restraint. At the time of
launch, the longitudinal axis of the impactor is within 2 degrees of
being horizontal and parallel to the vehicle longitudinal axis. The
direction of travel is posteriorly.
(d) Constrain the movement of the head form so that it travels
linearly along the path described in S5.2.5(c) of this section for not
less than 25 mm before making contact with the head restraint.
(e) Impact the anterior surface of the seat or head restraint at any
point with a height greater than 635 mm and within a distance of the
head restraint vertical centerline of 70 mm.
S5.2.6 Procedures for height retention. Demonstrate compliance with
S4.2.6 of this section in accordance with S5.2.6 (a) through (d) of this
section.
(a) Adjust the adjustable head restraint so that its top is at any
of the following height positions at any backset position--
(1) For front outboard designated seating positions--
(i) The highest position; and
(ii) Not less than, but closest to 800 mm; and
(2) For rear outboard designated seating positions equipped with
head restraints--
(i) The highest position; and
(ii) Not less than, but closest to 750 mm.
(b)(1) Orient a cylindrical test device having a 165 2 mm diameter in plane view (perpendicular to the axis
of revolution), and a 152 mm length in profile (through the axis of
revolution) with a surface roughness of less than 1.6 [micro]m, root
mean square, such that the axis of the revolution is horizontal and in
the longitudinal vertical plane through the longitudinal centerline of
the head restraint. Position the midpoint of the bottom surface of the
cylinder in contact with the head restraint.
(2) Establish initial reference position by applying a vertical
downward load of 50 1 N.
(c) Increase the load at the rate of 250 50 N/
minute to at least 500 N and maintain this load for not less than 5
seconds.
(d) Reduce the load at the rate of 250 50 N/
minute to 50 1 N and determine the position of the
cylindrical device with respect to its initial reference position.
[[Page 537]]
S5.2.7 Procedures for backset retention, displacement, and strength.
Demonstrate compliance with S4.2.7 of this section in accordance with
S5.2.7 (a) and (b) of this section. The load vectors that generate
moment on the head restraint are initially contained in a vertical plane
parallel to the vehicle longitudinal centerline.
(a) Backset retention and displacement--
(1) Adjust the head restraint so that its top is at a height closest
to and not less than:
(i) 800 mm for front outboard designated seating positions (or the
highest position of adjustment for head restraints subject to
S4.2.1(a)(2)); and
(ii) 750 mm for rear outboard designated seating positions equipped
with head restraints (or the highest position of adjustment for rear
head restraints subject to S4.2.1(b)(2)).
(2) Adjust the head restraint to any backset position.
(3) In the seat, place a test device having the back pan dimensions
and torso reference line (vertical center line), when viewed laterally,
with the head room probe in the full back position, of the three
dimensional SAE J826 (rev. Jul 95) manikin;
(4) Establish the displaced torso reference line by creating a
posterior moment of 373 7.5 Nm about the H-point
by applying a force to the seat back through the back pan at the rate of
187 37 Nm/minute. The initial location on the back
pan of the moment generating force vector has a height of 290 mm 13 mm. Apply the force vector normal to the torso
reference line and maintain it within 2 degrees of a vertical plane
parallel to the vehicle longitudinal centerline. Constrain the back pan
to rotate about the H-point. Rotate the force vector direction with the
back pan.
(5) Maintain the position of the back pan as established in S5.2.7
(4) of this section. Using a 165 2 mm diameter
spherical head form with a surface roughness of less than 1.6 [micro]m,
root mean square, establish the head form initial reference position by
applying, perpendicular to the displaced torso reference line, a
posterior initial load at the seat centerline at a height 65 3 mm below the top of the head restraint that will
produce a 37 0.7 Nm moment about the H-point.
Measure the posterior displacement of the head form during the
application of the load.
(6) Increase the initial load at the rate of 187 37 Nm/minute until a 373 7.5 Nm
moment about the H-point is produced. Maintain the load level producing
that moment for not less than 5 seconds and then measure the posterior
displacement of the head form relative to the displaced torso reference
line.
(7) Reduce the load at the rate of 187 37 Nm/
minute until a 37 0.7 Nm moment about the H-point
is produced. While maintaining the load level producing that moment,
measure the posterior displacement of the head form position with
respect to its initial reference position; and
(b) Strength. Increase the load specified in S5.2.7(a)(7) of this
section at the rate of 250 50 N/minute to at least
890 N and maintain this load level for not less than 5 seconds.
S5.3 Procedures for dynamic performance. Demonstrate compliance with
S4.3 of this section in accordance with S5.3.1 though S5.3.9 of this
section with a 50th percentile male Hybrid III test dummy specified in
49 CFR part 572 subpart E, with the head restraint midway between the
lowest and the highest position of adjustment, and at any position of
backset adjustment.
S5.3.1 Mount the vehicle on a dynamic test platform at the vehicle
attitude set forth in S13.3 of Sec. 571.208, so that the longitudinal
centerline of the vehicle is parallel to the direction of the test
platform travel and so that movement between the base of the vehicle and
the test platform is prevented. Instrument the platform with an
accelerometer and data processing system. Position the accelerometer
sensitive axis parallel to the direction of test platform travel.
S5.3.2 Remove the tires, wheels, fluids, and all unsecured
components. Remove or rigidly secure the engine, transmission, axles,
exhaust, vehicle frame and any other vehicle component necessary to
assure that all points on the acceleration vs. time plot measured by an
accelerometer on the dynamic test platform fall within the corridor
described in Figure 1 and Table 1.
S5.3.3 Place any moveable windows in the fully open position.
[[Page 538]]
S5.3.4 Seat adjustment. At each outboard designated seating
position, using any control that primarily moves the entire seat
vertically, place the seat in the lowest position. Using any control
that primarily moves the entire seat in the fore and aft directions,
place the seat midway between the forwardmost and rearmost position. If
an adjustment position does not exist midway between the forwardmost and
rearmost positions, the closest adjustment position to the rear of the
midpoint is used. Adjust the seat cushion and seat back, without using
any controls that move the entire seat, as required by S5 and S5.1 of
this section. If the specified position of the H-point can be achieved
with a range of seat cushion inclination angles, adjust the seat
inclination such that the most forward part of the seat cushion is at
its lowest position with respect to the most rearward part. If the head
restraint is adjustable, adjust the top of the head restraint to a
position midway between the lowest position of adjustment and the
highest position of adjustment. If an adjustment position midway between
the lowest and the highest position does not exist, adjust the head
restraint to a position below and nearest to midway between the lowest
position of adjustment and the highest position of adjustment.
S5.3.5 Seat belt adjustment. Prior to placing the Type 2 seat belt
around the test dummy, fully extend the webbing from the seat belt
retractor(s) and release it three times to remove slack. If an
adjustable seat belt D-ring anchorage exists, place it in the adjustment
position closest to the mid-position. If an adjustment position does not
exist midway between the highest and lowest position, the closest
adjustment position above the midpoint is used.
S5.3.6 Dress and adjust each test dummy as specified in S8.1.8.2
through S8.1.8.3 of Sec. 571.208.
S5.3.7 Test dummy positioning procedure. Place a test dummy at each
outboard designated seating position equipped with a head restraint.
S5.3.7.1 Head. The transverse instrumentation platform of the head
is level within \1/2\ degree. To level the head of the test dummy, the
following sequences is followed. First, adjust the position of the H
point within the limits set forth in S10.4.2.1 of Sec. 571.208 to level
the transverse instrumentation platform of the head of the test dummy.
If the transverse instrumentation platform of the head is still not
level, then adjust the pelvic angle of the test dummy. If the transverse
instrumentation platform of the head is still not level, then adjust the
neck bracket of the dummy the minimum amount necessary from the non-
adjusted ``0'' setting to ensure that the transverse instrumentation
platform of the head is horizontal within \1/2\ degree. The test dummy
remains within the limits specified in S10.4.2.1 of Sec. 571.208 after
any adjustment of the neck bracket.
S5.3.7.2 Upper arms and hands. Position each test dummy as specified
in S10.2 and S10.3 of Sec. 571.208.
S5.3.7.3 Torso. Position each test dummy as specified in S10.4.1.1,
S10.4.1.2, and S10.4.2.1 of Sec. 571.208, except that the midsagittal
plane of the dummy is aligned within 15 mm of the head restraint
centerline. If the midsagittal plane of the dummy cannot be aligned
within 15 mm of the head restraint centerline then align the midsagittal
plane of the dummy as close as possible to the head restraint
centerline.
S5.3.7.4 Legs. Position each test dummy as specified in S10.5 of
Sec. 571.208, except that final adjustment to accommodate placement of
the feet in accordance with S5.3.7.4 of this section is permitted.
S5.3.7.5 Feet. Position each test dummy as specified in S10.6 of
Sec. 571.208, except that for rear outboard designated seating
positions the feet of the test dummy are placed flat on the floorpan and
beneath the front seat as far forward as possible without front seat
interference. For rear outboard designated seating position, if
necessary, the distance between the knees can be changed in order to
place the feet beneath the seat.
S5.3.8 Accelerate the dynamic test platform to 17.3 0.6 km/h. All of the points on the acceleration vs. time
curve fall within the corridor described in Figure 1 and Table 1 when
filtered to channel class 60, as specified in the SAE Recommended
Practice J211/1
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(rev. Mar 95). Measure the maximum posterior angular displacement.
S5.3.9 Calculate the angular displacement from the output of
instrumentation placed in the torso and head of the test dummy and an
algorithm capable of determining the relative angular displacement to
within one degree and conforming to the requirements of a 600
Hz channel class, as specified in SAE Recommended Practice
J211/1, (rev. Mar 95). No data generated after 200 ms from the beginning
of the forward acceleration are used in determining angular displacement
of the head with respect to the torso.
S5.3.10 Calculate the HIC15 from the output of
instrumentation placed in the head of the test dummy, using the equation
in S4.3.1(b) of this section and conforming to the requirements for a
1000 Hz channel class as specified in SAE Recommended
Practice J211/1 (rev. Mar 95). No data generated after 200 ms from the
beginning of the forward acceleration are used in determining HIC.
S5.4 Procedures for folding or retracting head restraints for
unoccupied rear outboard designated seating positions.
(a) Demonstrate compliance with S4.4 (a) of this section, using a
5th percentile female Hybrid III test dummy specified in 49 CFR part
572, subpart O, in accordance with the following procedure--
(1) Position the test dummy in the seat such that the dummy's
midsaggital plane is aligned within the 15 mm of the head restraint
centerline and is parallel to a vertical plane parallel to the vehicle
longitudinal centerline.
(2) Hold the dummy's thighs down and push rearward on the upper
torso to maximize the dummy's pelvic angle.
(3) Place the legs as close as possible to 90 degrees to the thighs.
Push rearward on the dummy's knees to force the pelvis into the seat so
there is no gap between the pelvis and the seat back or until contact
occurs between the back of the dummy's calves and the front of the seat
cushion such that the angle between the dummy's thighs and legs begins
to change.
(4) Note the position of the head restraint. Remove the dummy from
the seat. If the head restraint returns to a retracted position upon
removal of the dummy, manually place it in the noted position. Determine
compliance with the height requirements of S4.2.1 of this section by
using the test procedures of S5.2.1 of this section.
(b) Demonstrate compliance with S4.4 (b) of this section in
accordance with the following procedure:
(1) Place the rear head restraint in any position meeting the
requirements of S4.2 of this section;
(2) Strike a line on the head restraint. Measure the angle or range
of angles of the head restraint reference line as projected onto a
vertical longitudinal vehicle plane;
(3) Fold or retract the head restraint to a position in which its
minimum height is less than that specified in S4.2.1 (b) of this section
or in which its backset is more than that specified in S4.2.3 of this
section;
(4) Determine the minimum change in the head restraint reference
line angle as projected onto a vertical longitudinal vehicle plane from
the angle or range of angles measured in S5.4(b)(2) of this section.
Table 1 of Sec. 571.202a--Sled Pulse Corridor Reference Point
Locations.
------------------------------------------------------------------------
Time Acceleration
Reference point (ms) (m/s\2\)
------------------------------------------------------------------------
A................................................ 0 10
B................................................ 28 94
C................................................ 60 94
D................................................ 92 0
E................................................ 4 0
F................................................ 38.5 80
G................................................ 49.5 80
H................................................ 84 0
------------------------------------------------------------------------
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[69 FR 74884, Dec. 14, 2004, as amended at 71 FR 12148, Mar. 9, 2006]