[Federal Register Volume 64, Number 82 (Thursday, April 29, 1999)]
[Proposed Rules]
[Pages 23037-23039]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-10777]


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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571

[Docket No. NHTSA-98-4167; Notice 1]


Federal Motor Vehicle Safety Standards; Child Restraint Systems

AGENCY: National Highway Traffic Safety Administration (NHTSA), DOT.

ACTION: Denial of petition for rulemaking.

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SUMMARY: This document denies a petition for rulemaking requesting that 
NHTSA amend Standard 213, ``Child Restraint Systems,'' to delete the 
head excursion requirement for rear-facing convertible restraints. 
Petitioners believe that infants should be rear-facing until at least 1 
year of age, and that the head excursion limit in Standard 213 makes it 
unnecessarily difficult for manufacturers to recommend their restraints 
be used rear-facing for children of at least that age. NHTSA is denying 
the petition because the head excursion limit serves a safety need and 
there are unknown safety consequences to the petitioners' requested 
action. Second, more and more manufacturers are able to meet the head 
excursion requirement and certify rear-facing restraints for children 
older than 1 year in age. Further, the petitioners did not provide--and 
NHTSA has not identified--any data which indicate that injuries could 
have been prevented by the requested amendment.

FOR FURTHER INFORMATION CONTACT: For nonlegal issues: Mike Huntley, 
Office of Crashworthiness Standards, Special Vehicle and Systems 
Division (telephone 202-366-0029).
    For legal issues: Deirdre Fujita, Office of the Chief Counsel (202-
366-2992). Both can be reached at the National Highway Traffic Safety 
Administration, 400 Seventh St., SW, Washington, DC 20590.

SUPPLEMENTARY INFORMATION:

I. Petitioners' Request

    On March 1, 1997, Stephanie Trombello and Deborah Stewart, 
Executive Director and Technical Consultant, respectively, of 
SafetyBeltSafe U.S.A., Inglewood, California, petitioned NHTSA to amend 
Federal Motor Vehicle Safety Standard No. 213, ``Child Restraint 
Systems'' (49 CFR 571.213), concerning certain labeling and occupant 
excursion requirements in the standard. Petitioners believe that 
infants should be rear-facing until at least 1 year of age, and that 
the head excursion limit in Standard 213 makes it unnecessarily 
difficult for manufacturers of convertible 1 child restraint 
systems to recommend that their restraints be used rear-facing until 
the child is at least that age.
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    \1\ A convertible restraint is used to restrain children from 
birth to about 40 lb. When restraining an infant, the restraint is 
positioned so that it faces the rear of a vehicle. When restraining 
a toddler, the restraint is positioned so that it faces the front of 
a vehicle.
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    Standard 213 specifies performance requirements that a child 
restraint must meet when tested with dummies representing the range of 
children for which that child restraint is recommended. Under Standard 
213's requirements, child restraints recommended for use by children 
weighing over 22 lb are tested with a test dummy representing a 3-year-
old child. So tested, they must meet all performance requirements of 
the standard, including limits on how far they allow the rear-facing 
dummy's head to extend beyond and above the top of the child restraint 
in a 30-mph dynamic test. (This document refers to these limits as the 
head excursion limits.) The head excursion limits are set forth in 
S5.1.3.2 of Standard 213, as follows:

    S5.1.3.2. Rear-facing child restraint systems. In the case of 
each rear-facing child restraint system, all portions of the test 
dummy's torso shall be retained within the system and neither of the 
target points on either side of the dummy's head and on the 
transverse axis passing through the center of mass of the dummy's 
head and perpendicular to the head's midsagittal plane, shall pass 
through the transverse orthogonal planes whose intersection contains 
the forward-most and top-most points on the child restraint system 
surfaces.

    The petitioners request that Standard 213 be amended to exclude 
convertible child restraints from the head excursion limit when the 
restraint is tested rear-facing with the 33 lb dummy. Petitioners state 
that, but for the head excursion limit,

    (S)ome currently available convertible safety seats have 
performed well in crash tests with the 33-pound dummy in the rear-
facing position. (However, we) understand that the reason the 
manufacturers have hesitated to change their instructions to 
encourage rear-facing use for heavier babies is that the child's 
head could ramp up and over the top edge of the car seat in a head-
on collision.

    Petitioners believe that injuries will be prevented if NHTSA amends 
the standard as they request. Twenty-two (22) lb is the weight of a 
50th percentile 12-month-old. Petitioners state that many babies reach 
22 lb at six months of age or even earlier. They believe that current 
labeling on convertible child restraints results in parents of 
``heavy'' infants turning the child forward when the child is less than 
1 year.
    Petitioners believe that the head excursion limit is unnecessary 
because a heavy one-year-old is much shorter than the 33 lb (3-year-
old) dummy. They suggest that in lieu of the head excursion 
requirement, parents can be instructed, by way of a label, to limit use 
of the rear-facing child restraint based on the child's height. They 
suggest a statement such as ``This safety seat may be used in the rear-
facing position until the child weighs 30 pounds if the child's head is 
below the top edge (or within __ inches of the top edge) of the seat.''

II. Evaluation of Petition

    NHTSA is denying the petition for the reasons set forth below.

1. Rear-Facing Restraints Certified Above 22 Lb

    Infants should be transported rear-facing until the child's 
skeletal and muscular structure can develop to where they can more 
safely withstand crash forces in a forward-facing position, which 
typically occurs at around age 1. Transporting infants rear-facing 
spreads crash forces evenly across the infant's back and shoulders, the 
strongest part of the child's body.

[[Page 23038]]

Further, the infant's head will be supported by the seating surface in 
a crash, which helps reduce the likelihood of severe neck injuries in a 
crash. To better enable child restraint manufacturers to produce rear-
facing child restraints for children up to age 1, Standard 213 
specifies that child restraints will not be tested with the 3-year-old 
child test dummy unless the restraint is recommended for use by a child 
weighing more than the 50th percentile 12-month-old (which weighs 22 
lb) (see July 6, 1995 final rule, 60 FR 50477).2
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    \2\ The interrelationship of weight, height, and age as they 
relate to positioning an infant rear facing in a child restraint 
system was discussed at length in the development of this rule, 
which amended FMVSS No. 213 to add a greater array of sizes and 
weights of test dummies for use in the standard's compliance tests.
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    While positioning an infant rear-facing is generally preferable to 
facing the child forward, that may not be the case if the child 
restraint system is unable to adequately limit the head excursion of 
the child, or otherwise meet the performance requirements of Standard 
213. If the head excursion limit were deleted, that would negate the 
agency's ability to evaluate the restraint's ability to limit the 
upwards ramping of a child's head in a crash and would hamper the 
evaluation of the restraint's ability to prevent the partial or full 
ejection of the dummy.
    Petitioners state that a ``heavy'' 1-year-old is much shorter than 
the 33 lb dummy, but do not provide any values quantifying the height 
difference. Available data indicate only a 3.5 centimeter (cm) 
difference in height. NHTSA evaluated data in a 1975 report by the 
University of Michigan, ``Physical Characteristics of Children as 
Related to Death and Injury for Consumer Product Safety Design,'' May 
1975 (UM-HSRI-BI-75-5, HS 017743), to determine the difference in 
sitting heights between a 95th percentile 1-year-old and a 50th 
percentile 3-year-old child. The sitting height (crown-rump) of the 
95th percentile 1-year-old (combined sexes) is approximately 50 cm, 
while that of the 50th percentile 3-year-old (combined sexes) is 53.5 
cm.3 The agency believes that the 3.5 cm height difference 
is not of a magnitude to render the 3-year-old dummy inappropriate as a 
test device for evaluating the restraint's ability to limit the head 
excursion of a 95th percentile 12-month-old child. To the contrary, the 
difference between the two may be unsubstantial.
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    \3\ The agency's 3-year-old dummy represents a 50th percentile 
male child. Data on the sitting height of a 50th percentile male are 
not available.
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    Petitioners have also not provided data showing that a ``heavy'' 1-
year-old would have adequate head support in a crash without a head 
excursion limit in the standard. They believe that a child whose head 
is ``below the top edge (or within __ inches of the top edge) of the 
seat'' will be adequately protected, but do not specify what value 
should be specified in the blank. They also do not provide data 
supporting their belief that a child restraint will adequately support 
a child's head which is ``below the top edge'' or below that 
unspecified location on the child restraint. NHTSA is concerned that 
not enough is known about the safety consequences of reducing the 
stringency of the head excursion requirement for rear-facing child 
restraints.
    In addition to the above consideration, the current requirement is 
practicable. Some manufacturers have been able to develop convertible 
child restraints that they have certified as meeting Standard 213 when 
tested rear-facing with the 33 lb dummy. NHTSA is aware of at least 
three manufacturers who currently market convertible child restraints 
that are certified for children weighing more than 22 lb, in the rear-
facing position. Century, Evenflo and Britax have all developed 
products which they certify meet all requirements of Standard 213 when 
tested in the rear-facing position with the 33 lb dummy. Thus, NHTSA 
believes that rear-facing restraints are available to families with 
``heavy'' infants that exceed 22 lb prior to 1 year of age.
    In summary, petitioners state that ``although the 3-year-old dummy 
may be too tall for full head support in the rear-facing position, a 
heavy 1-year-old is much shorter,'' but did not provide any technical 
rationale to support eliminating the excursion requirements of the 
standard when testing convertible restraints in the rear facing 
position with the 3-year-old dummy. Petitioners did not explain why the 
head excursion limit should be relaxed given the insubstantial sitting 
height difference between an average 3-year-old child and a ``heavy'' 
1-year-old child, nor did they explain the extent to which the head 
excursion limit could be relaxed given that height difference. These 
factors, in conjunction with the knowledge that various manufacturers 
have developed convertible restraints that meet the current 
requirements of the standard while tested rear-facing with the 33 lb, 
3-year-old dummy, lead the agency to believe that the current excursion 
requirement does not impose an unreasonable impediment to restraint 
manufacturers in the design of rear-facing restraints for children over 
22 lb.

2. Excursion Requirements; Total Height Considerations

    Petitioners also recommend that Standard 213's labeling 
requirements should be amended such that ``references to the total 
height of the child should be deleted, since the only significant 
measurements are the child's weight and the length of the torso.'' (The 
standard currently requires that manufacturers label their child 
restraints with information on both the height and weight of children 
for whom the restraint is recommended.) The agency discussed at length 
the relevancy of height as a significant criterion in the development, 
evaluation, and certification of child restraints in a 1995 rulemaking 
to incorporate the new set of test dummies into Standard 213 for 
compliance testing.
    In the notice of proposed rulemaking (NPRM) for that regulation, 
NHTSA had proposed that Standard 213 should require that manufacturers 
base their height recommendations on the sitting height of the child 
(51 FR 12225, March 16, 1994). In response to the NPRM, commenters 
generally agreed that the height of a child is an important factor in 
the certification and proper use of child restraint systems. While some 
supported the use of a sitting height criterion as had been proposed by 
the agency in the NPRM, others objected to its use because of concerns 
regarding the complexity and potential misinterpretation of information 
by users of these child restraint systems. Those who opposed adoption 
of a sitting height criterion proposed incorporation of a sitting 
height limit which references a readily identifiable body landmark 
(such as the top of the ears or top of the head) in relation to the top 
of the head restraint in conjunction with modified labeling 
requirements to convey information about the proper use of the child 
restraint to the consumer to prevent whiplash-type injuries.
    In the final rule (July 6, 1995, 60 FR 35127), the agency 
reconfirmed that information about the suitability of a restraint for 
children of certain heights serves a useful purpose in that it helps 
ensure the proper fit of a restraint to the child. At the same time, 
the agency acknowledged that consumers may not know the sitting height 
of their child as well as they know standing height. The latter is 
routinely measured by pediatricians and provided to parents during the 
child's medical examinations. Because standing height is more familiar 
to parents, the final rule specified recommended standing height,

[[Page 23039]]

rather than sitting height, to be on the label.
    Since the existing Standard 213 required manufacturers to label 
each child restraint with recommendations for the maximum height of 
children who can safely occupy the system, and because NHTSA was 
unconvinced of a need to change to sitting height, the final rule 
maintained the status quo. Petitioners have not provided any 
information supporting their request to change to sitting height and 
the agency is unaware of any reason to amend the standard as they 
suggest. Accordingly, the agency is denying this request.

3. Crash Data

    Underlying the petition is the implication that infants weighing 
over 22 lb are being injured because parents position them forward-
facing in a vehicle before the infants are 1 year of age. Petitioners 
did not provide any data or statistics indicating a greater incidence 
of neck and spinal cord injuries for this segment of the population. 
NHTSA examined the agency's National Automotive Sampling System (NASS) 
General Estimates System (GES) 4 records for the years 1988-
1996 for those crashes (1) involving an infant under 1 year of age, and 
(2) where both the child's weight and the child restraint orientation 
(rear or forward facing) were known. In 328 total cases investigated by 
NASS , there were no reported incidences of serious spine or other 
neck-related injuries. Seventeen (17) percent of the 328 cases (55 of 
328) involved infants weighing between 23 and 30 lb who were positioned 
forward facing in his/her child restraint at the time of the crash, but 
in only one case did the child receive a serious (AIS level 3 or 
greater) injury. Injuries to heavy infants placed forward-facing in 
vehicles have not occurred with any frequency.5
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    \4\ Data for the General Estimates System (GES) come from a 
nationally representative sample of police reported motor vehicle 
crashes of all types, from minor to fatal. The system began 
operation in 1988, and was created to identify traffic safety 
problem areas, provide a basis for regulatory and consumer 
initiatives, and form the basis for cost and benefit analyses of 
traffic safety initiatives. The information is used to estimate how 
many motor vehicle crashes of different kinds take place, and what 
happens when they occur. Although various sources suggest that about 
half the motor vehicle crashes in the country are not reported to 
the police, the majority of these unreported crashes involve only 
minor property damage and no significant personal injury. By 
restricting attention to police-reported crashes, the GES 
concentrates on those crashes of greatest concern to the highway 
safety community and the general public.
    \5\ The vast majority (273 of 328, or 83 percent) of reported 
cases involved infants weighing 22 lb or less. Nearly one half (47 
percent) of these infants were positioned forward-facing in their 
child restraints. This clearly suggests that nearly one half of the 
adults placing the infants in the child restraints either: (1) Were 
unaware that infants are safest rear-facing in child restraints, or 
(2) chose to ignore the manufacturer's recommendations and placed 
their child forward-facing in the restraint. This suggests a need to 
better inform parents about the need to properly position infants 
weighing less than 22 lb in vehicles.
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    In accordance with 49 CFR part 552, this completes the agency's 
review of the petition. For the aforementioned reasons, the agency has 
decided not to amend Standard 213 at this time to afford child 
restraint manufacturers greater latitude in certifying rear-facing 
convertible restraints. NHTSA has concluded that there is no reasonable 
possibility that the amendment requested by the petitioners would be 
issued at the conclusion of the rulemaking proceeding. Accordingly, the 
petition is denied.

    Authority: 49 U.S.C. 322, 30111, 30115, 30117 and 30166; 
delegation of authority at 49 CFR 1.50

    Issued on April 20, 1999.

L. Robert Shelton,

Associate Administrator for Safety Performance Standards.
[FR Doc. 99-10777 Filed 4-28-99; 8:45 am]
BILLING CODE 4910-59-P