[Federal Register Volume 87, Number 125 (Thursday, June 30, 2022)]
[Rules and Regulations]
[Pages 39234-39317]
[FR Doc No: 2022-13658]

Vol. 87

Thursday,

No. 125

June 30, 2022

Part III

Department of Homeland Security

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49 Part 571

Federal Motor Vehicle Safety Standards; Child Restraint Systems, Child
Restraint Systems--Side Impact Protection, Incorporation by Reference;
Final Rule

Federal Register / Vol. 87 , No. 125 / Thursday, June 30, 2022 /
Rules and Regulations

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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571

[Docket No. NHTSA-2022-0051]
RIN 2127-AK95

Federal Motor Vehicle Safety Standards; Child Restraint Systems,
Child Restraint Systems--Side Impact Protection, Incorporation by
Reference

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

ACTION: Final rule.

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SUMMARY: This final rule amends Federal Motor Vehicle Safety Standard
(FMVSS) (Standard) No. 213, ``Child restraint systems,'' and adds FMVSS
No. 213a, which is referenced by Standard No. 213. This final rule
fulfills a statutory mandate set forth in the ``Moving Ahead for
Progress in the 21st Century Act'' (MAP-21) that directed the Secretary
of Transportation (NHTSA by delegation) to issue a final rule to
improve the protection of children seated in child restraint systems
during side impacts.

DATES:
    Effective date: August 1, 2022. The incorporation by reference of
the publications listed in the rule is approved by the Director of the
Federal Register as of August 1, 2022.
    Compliance date: June 30, 2025. Optional early compliance is
permitted.
    Petitions for reconsideration: Petitions for reconsideration of
this final rule must be received no later than August 15, 2022.

ADDRESSES: Petitions for reconsideration of this final rule must refer
to the docket and notice number set forth above and be submitted to the
Administrator, National Highway Traffic Safety Administration, 1200 New
Jersey Avenue SE, Washington, DC 20590. Note that all petitions
received will be posted without change to http://www.regulations.gov,
including any personal information provided. To facilitate social
distancing due to COVID-19, please email a copy of the petition to
[email protected].
    Privacy Act. The petition will be placed in the docket. Anyone is
able to search the electronic form of all documents received into any
of our dockets by the name of the individual submitting the comment (or
signing the comment, if submitted on behalf of an association,
business, labor union, etc.). You may review DOT's complete Privacy Act
Statement in the Federal Register published on April 11, 2000 (Volume
65, Number 70; Pages 19477-78) or you may visit https://www.transportation.gov/individuals/privacy/privacy-act-system-records-notices.

FOR FURTHER INFORMATION CONTACT: For technical issues, you may call
Cristina Echemendia, Office of Crashworthiness Standards, telephone
202-366-6345, email [email protected]. For legal issues,
Deirdre Fujita or Hannah Fish, Office of the Chief Counsel, telephone
202-366-2992, email [email protected] or [email protected]. The
mailing address of these officials is the National Highway Traffic
Safety Administration, U.S. Department of Transportation, 1200 New
Jersey Avenue SE, West Building, Washington, DC 20590.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Executive Summary
II. Safety Need
III. Statutory Mandate
IV. Guiding Principles
V. Overview of the NPRM and Comments Received
    a. Overview of the NPRM
    b. Summary of the Comments
VI. Response to the Comments (Wide-Reaching Issues)
    a. Are efforts better spent elsewhere on child restraint
systems?
    b. Will child restraints become excessively large and heavy?
    c. More Bulk Is Not Necessarily Advantageous; the 2017 Test
Program
    d. The 40-lb Limit for Coverage of the Standard
    e. Improving Side Impact Protection for Children Older Than 3-
Years-Old
    f. Weight as a Limiting Factor
    g. Labeling CRSs for Children Weighing Over 18.1 kg (40 lb)
    1. Label as ``Not Tested in Side Impacts''
    2. Head Under Window Sill
VII. Aspects of the FMVSS 213a Test Procedure
    a. Overview
    b. Side Impact Seat Assembly Characteristics
    1. Seat Characteristics
    i. Rear Seat Cushion Stiffness
    ii. Lower Anchorages and Top Tether Anchorages of the CRAS
    2. Door Characteristics
    i Beltline Height
    ii. Door and Armrest Thickness and Stiffness
    3. Honeycomb
    4. SISA Technical Drawings
    5. Other Testing Issues
    i. Right-Side Impacts
    ii. Sliding Seat Bearings
    iii. Seat Belt Interference
    c. Sled Kinematic Parameters
    1. General
    2. Specific Issues
    i. Sliding Seat Acceleration Profile
    ii. Tuning the Test To Account for Lighter Dummies
    iii. Acceleration Corridor
    3. Door Parameters
    4. Relative Door Velocity Profile
    5. Relative Velocity at Impact Time (T0)--Tolerance
    6. Longitudinal Crash Component
    d. Test Set Up and Procedure
    1. CRS Attachment
    i. Lower Anchor and/or Seat Belt CRS Installation
    ii. Tethered vs. Non-Tethered CRS Installation
    iii. Distance Between Edge of Armrest and Edge of Seat
    e. Dummy Positioning
    f. Dummy Selection
    g. Miscellaneous Comments on the Test Procedure, Including Test
Setup, Sled Instrumentation, and Data Processing
    h. Additional Changes
VIII. Performance Requirements
    a. Q3s
    1. Q3s Sourcing
    2. Biofidelity Issues
    3. Aspects of Testing With the Q3s
    i. Reversibility
    ii. HIII 3-Year-Old Child Test Dummy as an Alternative
    4. Q3s Performance Measures
    i. Head Injury Criterion (HIC)
    ii. Head Contact (Not Assessed)
    iii. Chest Deflection
    b. CRABI 12-Month-Old
    1. Alternative ATDs
    2. Durability
    3. Head-to-Door Contact
    4. Component Test
    5. CRS System Integrity and Energy Distribution
IX. Repeatability and Reproducibility
X. Lead Time and Effective Date
XI. Regulatory Notices and Analyses

    This final rule amends FMVSS No. 213, ``Child restraint systems,''
to establish side impact performance requirements for child restraint
systems (CRS) designed to seat children weighing up to 18.1 kilograms
(kg) (40 pounds (lb)), or for children in a height range that includes
heights up to 1100 millimeters (43.3 inches.) The side impact
performance requirements are established in a new FMVSS No. 213a, which
is referenced by Standard No. 213. This final rule fulfills a statutory
mandate set forth in MAP-21 that directed the Secretary of
Transportation (NHTSA by delegation) to issue a final rule to improve
the protection of children seated in child restraint systems during
side impacts.
    Standard No. 213a requires child restraints designed to seat
children weighing up to 18.1 kg (40 lb), or for children in a height
range that includes heights up to 1100 millimeters (43.3 inches) to
meet performance criteria when tested in a dynamic test replicating a
vehicle-to-vehicle side impact. The child restraints must provide
proper restraint, manage side

crash forces, and protect against harmful head and chest contact with
intruding structures. In addition, child restraints will be required to
meet other performance requirements in the sled test to ensure, among
other things, the restraint can withstand crash forces from a side
impact without collapsing or fragmenting in a manner that could harm
the child. This new standard will reduce the number of children killed
or injured in side crashes.

I. Executive Summary

    Front and side crashes account for most child occupant fatalities.
FMVSS No. 213 currently specifies performance requirements that child
restraint systems (CRSs) must meet in a sled test simulating a frontal
impact. This final rule expands the standard to adopt a side impact
test. Child restraints subject to this final rule must pass the new
side impact test in addition to the frontal impact test.
    Impacts to the side of a vehicle rank almost equal to frontal
crashes as a source of occupant fatalities and serious injuries to
children ages 0 to 12 years. Side impacts are especially dangerous when
the impact is on the passenger compartment because, unlike a frontal or
rear-end crash, there are no substantial, energy absorbing structures
between the occupant and the impacting vehicle or object. The door
collapses into the passenger compartment and the occupants contact the
door relatively quickly after the crash at a high relative velocity.\1\
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    \1\ Kahane, November 1982, NHTSA Report No. DOT HS 806 314.
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    In a typical vehicle-to-vehicle side impact similar to the one
represented in Standard No. 214, ``Side impact protection'' (49 CFR
571.214), the striking vehicle first interacts with the door structure
of the struck vehicle and commences to crush the door, causing it to
intrude laterally into the vehicle compartment. The striking vehicle
then engages the sill of the struck vehicle and begins to push the
struck vehicle away. At this point, the occupant sitting on the struck
side of the vehicle experiences the struck vehicle seat moving away
from the impacting vehicle while the door intrudes towards him or her.
The intruding door impacts the occupant and the occupant is accelerated
with the door along the impact direction until the occupant reaches the
velocity of the struck and striking vehicle.
    Standard No. 214, protects against unreasonable risk of injury or
death to occupants in vehicle-to-vehicle crashes and other side
crashes. The standard has benefited all occupants,\2\ but due to their
size and fragility, infants and young children are dependent on child
restraint systems to supplement those protections. Child restraints
with internal harnesses (commonly called ``car seats,'' ``child seats''
or ``safety seats'') are highly effective safety devices. Although
child seats are not currently subject to side impact testing, NHTSA
estimates that these types of child restraints are already 42 percent
effective in preventing death in side crashes of children 0- to 3-
years-old.\3\ This estimated degree of effectiveness is high, and is
only 11 percentage points lower than Child Restraint System (CRS)
effectiveness in frontal crashes (53 percent). Child safety seats are
effective because they restrain the child within the child seat and
prevent harmful contact with interior vehicle components, and have
padding and an outer shell structure that shields the child and absorbs
some of the crash forces.
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    \2\ Kahane, C.J. (2015, January). Lives saved by vehicle safety
technologies and associated Federal Motor Vehicle Safety Standards,
1960 to 2012--Passenger cars and LTVs--With reviews of 26 FMVSS and
the effectiveness of their associated safety technologies in
reducing fatalities, injuries, and crashes. (Report No. DOT HS 812
069). Washington, DC: National Highway Traffic Safety
Administration. Link: https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/812069.
    \3\ NHTSA conducted an analysis of the Fatality Analysis
Reporting System (FARS) data files of real world fatal non-rollover
frontal and side crashes of passenger cars and light trucks and vans
involving children for the years 1995 to 2009. From this analysis,
the agency estimated the effectiveness of CRSs in preventing
fatalities among 0- to 3-year-old children to be 42 percent in side
crashes and 53 percent in frontal crashes. The analysis method is
similar to that reported in the NCSA Research Note, ``Revised
Estimates of Child Restraint Effectiveness,'' DOT HS 96855 and is
also detailed in the technical report in the NPRM docket (https://www.regulations.gov/document/NHTSA-2014-0012-0002).
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    Because MAP-21 directed NHTSA to amend FMVSS No. 213 to improve
side impact protection, NHTSA designed this final rule to work within
the framework of the existing frontal standard. Child restraint systems
are tested in FMVSS No. 213 when attached to a standardized seat
assembly representative of a passenger vehicle seat. Child restraints
are tested with anthropomorphic test devices (ATDs) (test dummies)
representative of the children for whom the CRS is recommended.\4\
FMVSS No. 213 requires child restraints to limit the amount of inertial
load that can be exerted on the head and chest of the dummy during the
dynamic test. The standard requires child restraints to meet head
excursion \5\ limits to reduce the possibility of head injury from
contact with vehicle interior surfaces and ejection. Child restraints
must also maintain system integrity (i.e., not fracture or separate in
such a way as to harm a child), and have no contactable surface that
can harm a child in a crash. There are requirements to ensure belt
webbing can safely restrain the child, and that buckles can be swiftly
unlatched after a crash by an adult but cannot be easily unbuckled by
an unsupervised child. Child restraints other than booster seats and
harnesses \6\ must pass performance requirements when attached to the
standard seat assembly with only a lap belt,\7\ and, in a separate
assessment, with only the lower anchorages of a child restraint
anchorage system (CRAS).\8\ The CRSs must meet more stringent head
excursion requirements in another test where a top tether, if provided,
may be attached. Belt-positioning (booster) seats are tested on the
standard seat assembly using a Type 2 (lap and shoulder) belt.
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    \4\ Standard No. 213 specifies the use of test dummies
representing a newborn, a 12-month-old, 3- and 6-year-old, weighted
6-year-old, and 10-year-old child. The ATDs other than the newborn
are equipped with instrumentation measuring crash forces, but NHTSA
restricts some measurements from the weighted 6-year-old and 10-
year-old dummies due to technical limits of the dummies.
    \5\ Head excursion refers to the distance the dummy's head
translates forward in FMVSS No. 213's simulated frontal crash test.
    \6\ These types of child restraint systems are defined in FMVSS
No. 213.
    \7\ As explained in more detail below, NHTSA published an NPRM
on November 2, 2020 (85 FR 69388) to amend the standard seat
assembly in FMVSS No. 213 ``to better simulate a single
representative motor vehicle rear seat.'' Among other matters, the
NPRM proposes replacing the lap belt test with a lap and shoulder
belt (Type 2 belt) test.
    \8\ Commonly called ``LATCH,'' which refers to Lower Anchors and
Tethers for Children, an acronym developed to refer to the child
restraint anchorage system required by FMVSS No. 225 for
installation in motor vehicles (49 CFR 571.225, ``Child restraint
anchorage systems''). A child restraint anchorage system consists of
two lower anchorages, and one upper tether anchorage. Each lower
anchorage includes a rigid round rod, or ``bar,'' onto which a hook,
a jaw-like buckle or other connector can be snapped. The bars are
located at the intersection of the vehicle seat cushion and seat
back. The upper tether anchorage is a ring-like object to which the
upper tether of a child restraint system can be attached. FMVSS No.
213 requires CRSs to be equipped with attachments that enable the
CRS to attach to the vehicle's child restraint anchorage system.
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    This final rule establishes requirements for a side impact test
that are equivalent to those described above, and makes child restraint
systems even more protective of child occupants than they are now. It
adopts performance thresholds that ensure child restraints protect
against unreasonable risk of head and chest injury in side crashes, and
a performance test that objectively assesses and assures achievement of
such performance.

    The standard adopted by this final rule applies to child restraints
for children weighing up to 18.1 kg (40 lb) or for children up to 1100
millimeters (mm) (43.3 inches, or 3 feet, 7 inches) in standing
height.\9\ These children would be virtually all 3-year-olds and almost
all 4-year-olds. The 18.1 kg (40 lb) threshold is greater than the
weight of a 97th percentile 3-year-old (17.7 kg (39.3 lb)) and is
approximately the weight of an 85th percentile 4-year-old. The 1100 mm
(43.3 inches) height threshold is more than the height of a 97th
percentile 3-year-old (1024 mm (40.3 inches)) and corresponds to the
height of a 97th percentile 4-year-old. While the standard would apply
to child restraints that are recommended for use by children weighing
less than 18.1 kg (40 lb) or with heights under 1100 mm (43.3 inches),
as explained in a later section, the countermeasures (padding and side
structure) designed into a safety seat to meet the standard may also
provide side impact protection even as the child surpasses the 18.1 kg
(40 lb) or 1100 mm (43.3 inches) mark. Many child safety seats are
recommended for children much heavier than 18.1 kg (40 lb) or taller
than 1100 mm (43.3 inches). Children kept in such seats will benefit
from the countermeasures as they grow heavier than 18.1 kg (40 lb) or
taller than 1100 mm (43.3 inches). NHTSA quantified the benefits of
this rule for children up to age 4 but believes that children older
than age 4 would benefit from this final rule as well.
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    \9\ The agency added a height provision to make the new
standard's applicability clear to booster seat manufacturers who
choose not to label their restraints with a weight recommendation.
Although all current belt-positioning boosters are labeled with both
height and weight recommendations, FMVSS No. 213 permits
manufacturers of belt-positioning booster seats to delete the
reference to maximum weight (see FMVSS No. 213, S5.5.2(f)). In view
of that provision, for manufacturers that only provide a height
limit, the application section of FMVSS No. 213a will be clear as to
the applicability of the standard to their restraints. When this
final rule preamble refers to a ``40 lb weight limit'' we mean the
term to be synonymous with a height limit of 1100 mm for belt-
positioning boosters that only provide a height limit.
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    This final rule adopts a dynamic sled test simulating a full-scale
vehicle-to-vehicle side impact, which is the first-of-its-kind
simulating both an intruding door and a longitudinal crash component.
Child restraints recommended \10\ for children weighing 13.6 to 18.1 kg
(30 to 40 lb) are tested with an instrumented side impact test dummy
representing a 3-year-old child, called the Q3s dummy.\11\ Child
restraints designed for children weighing up to 13.6 kg (30 lb) are
tested with an established 12-month-old child test dummy (the 12-month-
old Child Restraint Air Bag Interaction (CRABI) dummy).\12\ The new
standard requires CRSs to restrain the dummy in the side test, manage
side crash forces and prevent harmful head contact with side
structures. Child restraints tested with the Q3s must also limit crash
forces to the dummy's chest. Following the dynamic side impact test,
child restraints will be assessed for their compliance with
requirements for system integrity, contactable surfaces, and buckle
release, just like they are following Standard No. 213's frontal impact
test.
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    \10\ When we describe a child restraint as ``recommended for''
children of a certain height or weight range, we mean the child
restraint manufacturer is manufacturing for sale, selling or
offering the CRS for sale as suitable for children in that height or
weight range.
    \11\ The Q3s is NHTSA's first child test dummy designed for side
impacts. NHTSA published a final rule on November 3, 2020 that
adopted the Q3s into NHTSA's regulation for anthropomorphic test
devices. 85 FR 69898.
    \12\ 49 CFR part 572, subpart R.
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Work Preceding This Final Rule

    NHTSA published the notice of proposed rulemaking (NPRM) preceding
this final rule on January 28, 2014 (79 FR 4570).\13\ Enhanced side
impact protection for children has long been a priority for NHTSA.
NHTSA laid the necessary groundwork for this final rule over the years
preceding and since the NPRM.\14\
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    \13\ Docket No. NHTSA 2014-0012.
    \14\ An overview of NHTSA's work developing FMVSS No. 213a can
be found in section IX of the January 28, 2014 NPRM, 79 FR at 4579-
4590.
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    To develop the NPRM, NHTSA examined data on the fatalities of young
children to see how children are killed and injured in side crashes,
the characteristics of the crashes that are injuring them, and the
types of injuries they suffer. Among CRS-restrained children killed in
side crashes, about 60 percent were in near-side impacts,\15\ leading
NHTSA to focus development on a near-side sled test. Intrusion was
found to be an important causative factor for moderate to serious
injury, which led NHTSA to concentrate on developing a side impact test
procedure that included intrusion into the occupant space.\16\ Data
indicated that children restrained in child restraints exhibited more
head injuries (59 percent) compared to torso injuries (22 percent) and
injuries to extremities (14 percent). NHTSA used these and other data
to develop the first-of-its-kind safety standard on child side impact
protection involving a near-side impact with a longitudinal crash
component and an intruding vehicle door.
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    \15\ See NPRM for this final rule, 79 FR 4570, Table 6. The NPRM
also noted that among CRS-restrained children with moderate to
higher severity injuries in side crashes, over 60 percent were in
near-side impacts (Table 8).
    \16\ Sherwood, see footnotes 40, 43 and 44 of the NPRM.
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    Following publication of the NPRM, NHTSA conducted a multi-year
research program from 2014 to 2016 to broaden the assessment of the Q3s
in providing repeatable and reproducible test results in side impact
testing. NHTSA designed a test program involving Humanetics Innovative
Solutions, Inc. (a dummy manufacturer), several private dummy owners
(CRS manufacturers), two independent testing labs, and NHTSA's Vehicle
Research and Test Center (VRTC). This work validated the performance
specifications of the NPRM, thus better ensuring that all future Q3s
dummies will be uniform, and provided information for NHTSA to use in
prescribing specifications for the Q3s. Information from that program
refined the set of engineering drawings and the series of dummy-only
impact tests used for production and qualification of the Q3s.\17\ The
test program enabled NHTSA to produce a set of fully-vetted engineering
specifications and an objective set of qualification standards. These
materials guarantee a high level of uniformity in any conforming Q3s
unit used to assess CRS performance in a side impact test.
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    \17\ The drawings describe every part on the dummy and may be
used to inspect dummies purchased from a dummy manufacturer. The
impact tests used by CRS manufacturers and other end-users serve as
a final check to ensure that the assembled dummy will perform as
prescribed by NHTSA in 49 CFR part 572.
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    Through research from 2015 to 2017, NHTSA adjusted the side impact
sled test assembly to reduce variability in results and more closely
align the assembly with current vehicle seats. In 2017, NHTSA undertook
fleet testing to obtain current data of CRS performance in side impacts
using the refined side impact seat assembly. These research projects
are discussed in detail in sections below in this preamble.

FMVSS No. 214 and No. 226

    FMVSS No. 214 played a critical role in developing this final rule.
NHTSA designed the side impact test to replicate the FMVSS No. 214
moving deformable barrier (MDB) test, as the MDB test simulates a full-
scale severe intersection collision of an impacting vehicle
(represented by a 1,360 kg (3,000 lb) MDB) traveling at 48.3 km/h (30
mph) striking the side of a test vehicle traveling at 24 km/h (15
mph).\18\ The MDB test replicated in this final rule involves a change
of velocity of

approximately 30.5 km/h (19 mph). NHTSA's analysis of field data (NASS-
CDS 1995-2009) found that 92 percent of near-side crashes for
restrained children (0 to 12 years-old) involved a change in velocity
of 30.5 km/h (19 mph) or lower.
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    \18\ FMVSS No. 214 MDB test (49 CFR 571.214, S7).
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    NHTSA designed this rule to account for the safety countermeasures
installed in vehicles to meet FMVSS No. 214 as practicably possible, to
make a realistic assessment of how a CRS will perform when subjected to
a side crash in the real world. To achieve this, NHTSA used compliance
test data from MDB tests where the vehicle passed the FMVSS No. 214
test, to replicate the characteristics of passenger-carrying vehicles
on the road. Furthermore, NHTSA designed FMVSS No. 213a to replicate a
collision of the striking MDB with a small vehicle rather than a larger
vehicle. NHTSA sought to replicate the characteristics of a small
passenger car, as opposed to a larger vehicle, because smaller cars
generally present a more demanding side impact test condition than
larger vehicles, since smaller cars generally have a higher change in
velocity than larger ones when impacted by the same MDB. Testing child
restraints under the more severe condition better ensures they will
provide the threshold level of protection required by the standard in
both small cars and large cars than if they were assessed under
conditions replicating large cars alone.
    Standard No. 214's pole test and FMVSS No. 226, Ejection
mitigation,\19\ were also integral to development of this final rule.
To meet the pole test, manufacturers equip passenger vehicles with side
air bags in front seating positions to protect against unreasonable
risk of head and chest injuries. To meet the pole test and FMVSS No.
226 requirements, manufacturers install side curtain air bags \20\ to
deploy in both side impacts and in rollovers, and design them to cover
all side windows at the vehicle's front, second and third rows, from
the roof line to the window sill. Consequently, vehicles are currently
produced with side curtain air bags that cover the entire side window
for front and rear row seats in both side impacts and rollovers. NHTSA
developed FMVSS No. 213a recognizing that these side curtain air bags
can protect passengers in rear seating positions against unreasonable
risk of head injury in side impact crashes, including older children in
booster seats.
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    \19\ FMVSS No. 214, S9. The pole test protects against side
crashes of passenger vehicles into structures such as telephone
poles and trees. It is a near-side impact. NHTSA established FMVSS
No. 226 (49 CFR 571. 226) in 2011 (76 FR 3212). The standard was
phased in starting in 2013, with full compliance required for
vehicles manufactured on or after September 1, 2017.
    \20\ In the final rule adopting the pole test into FMVSS No.
214, NHTSA anticipated that side curtain air bags installed to meet
FMVSS No. 214 would also be the countermeasure to meet the then-
pending ejection mitigation standard. NHTSA anticipated side impact
curtain air bags would extend to rear seating positions, and that
occupants in rear seating positions would benefit from the side
curtain air bags in side impacts. NHTSA stated: ``We believe that
manufacturers will install curtains in increasing numbers of
vehicles in response to this [FMVSS No. 214] final rule, the
voluntary commitment, and in anticipation of NHTSA's ejection
mitigation rulemaking. The curtains will provide head protection to
front and rear seat occupants in side impacts.'' 72 FR 51911, 51933;
Sept. 11, 2007.
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Details of This Final Rule

    The side impact sled test adopted by this final rule tests child
restraints in a manner that simulates the vehicle acceleration and
intruding door in a realistic side impact.\21\ The test seat assembly
on which a CRS is tested replicates the rear seating position nearest
to the side impact (near-side impact), as data show near-side impacts
are more injurious than far-side impacts, accounting for 81 percent of
moderate-to-critical injuries to restrained 0- to 3-year-old children
involved in side crashes. Most of these moderate-to-critical injuries
in near-side impacts are due to impact with interior surfaces in the
vehicle, and in near-side impacts, the interior surface is usually the
intruding door.\22\ In far-side impacts, the impact surfaces vary
considerably depending on the crash dynamics, and therefore are
difficult to characterize. For these reasons, standards established
worldwide for side impact protection of children focus on near-side
impacts, and FMVSS No. 214's moving deformable barrier and pole tests
involve only near-side impacts.
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    \21\ Data show that door intrusion is a causative factor for
moderate and serious injury to children in side impacts. Arbogast,
supra.
    \22\ Arbogast, et al., ``Injury Risks for Children in Child
Restraint Systems in Side Impact Crashes'' (2004); Arbogast, et al.,
``Protection of Children Restrained in Child Safety Seats in Side
Impact Crashes'' (2010); McCray et al., ``Injuries to Children One
to Three Years Old in Side Impact Crashes'' (2007).
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    This final rule applies to CRSs designed to seat children weighing
up to 18.1 kg (40 lb). NHTSA did not specify a limit above 18.1 kg (40
lb) because there is no side impact dummy representative of children
weighing more than 18.1 kg (40 lb) that is proven to provide the
reliable test measurements required of a test instrument used in the
FMVSSs.\23\ NHTSA is concerned that, without a valid test dummy, CRSs
for heavier children may ``pass'' a side impact test with a smaller
dummy but the dummy would not meaningfully assess the performance of
the CRS in protecting a larger child. Raising the limit above 18.1 kg
(40 lb) could engender a false sense of security that the CRS
adequately protects the heavier (larger) children when, in fact, the
assessment of performance was meaningless.
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    \23\ As noted earlier, the final rule applies to CRSs designed
for children weighing up to 18.1 kg (40 lb) and with standing height
up to 1100 mm (43.3 inches), which covers more than 97 percent of 3-
year-old children and about 85 percent of 4-year-old children. The
Q3s child dummy has weight and height representative of an average
3-year-old child.
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    NHTSA also decided to adopt a 40-lb weight limit after considering
the overall side impact protection provided by the FMVSSs and the
ongoing and potential work on child restraint safety. As explained
above, FMVSS No. 214's side impact tests were highly important to
NHTSA's design of FMVSS No. 213a and implementation of MAP-21. Children
over 40 lb would be provided side impact protection by remaining in a
CRS meeting FMVSS No. 213a for as long as the manufacturer recommends,
which typically exceeds a weight above 40 lb.\24\ When children outgrow
their safety seats, they transition to a booster seat, which on average
raises a seated child by 82 mm (3.22 inches),\25\ which would position
the child high enough to benefit from the vehicle's side curtain air
bags installed to meet Standards Nos. 214 and 226.
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    \24\ Out of the 107 models of forward-facing CRSs with internal
harness (convertibles, combination and all-in-one CRSs) in the
market, 85.9% have a maximum weight recommendation of 65 pounds,
10.2% have a maximum weight recommendation of 40 pounds and only
3.7% have a 50 pound maximum weight recommendation.
    \25\ The agency determined the height that a booster seat raises
a seated child (boosting height) by measuring the difference in the
H-point (marker on the hip) of the HIII-6-year-old dummy when the
dummy is seated on the side impact seat assembly specified in this
final rule (SISA) with no booster seat and when the dummy is seated
on the SISA in a booster seat. The boosting height measured for 15
booster seat models ranged from 43 mm (1.69 inches) to 104 mm (4.09
inches) with an average boosting height of 83 mm (3.26 inches). A
document with the measurements is docketed with this final rule.
---------------------------------------------------------------------------

    On November 2, 2020, NHTSA proposed to update FMVSS No. 213's
frontal impact test requirements, including the seat assembly and other
changes to the standard.\26\ In that

NPRM, NHTSA proposed that booster seats must be labeled as suitable
only for children weighing more than 18.1 kg (40 lb).\27\ This final
rule is consistent with that proposal to ensure that children remain in
car seats providing side impact protection longer, and will transition
to booster seats only when they are large enough to take advantage of
the vehicle's side air bag countermeasures.
---------------------------------------------------------------------------

    \26\ 85 FR 69388, November 2, 2020, Docket NHTSA-2020-0093.
Section 31501(b) of MAP-21 Subtitle E, directed NHTSA to undertake
rulemaking to amend the standard seat assembly in FMVSS No. 213 ``to
better simulate a single representative motor vehicle rear seat.''
Among other matters, as part of updating the standard seat assembly,
the NPRM proposed replacing the lap belt currently on the test
assembly with a lap and shoulder belt. MAP-21 requires NHTSA to
issue a final rule adopting an updated seat assembly.
    \27\ 85 FR at 69427, col. 3. NHTSA currently recommends that
children riding forward-facing should be restrained in CRSs with
internal harnesses (car safety seats) as long as possible before
transitioning to a booster seat. https://www.nhtsa.gov/equipment/car-seats-and-booster-seats#age-size-rec. FMVSS No. 213 currently
permits booster seats only to be recommended for children weighing
at least 13.6 kg (30 lb) (S5.5.2(f)). Based on an analysis of field
data and other considerations, NHTSA believes the 13.6 kg (30 lb)
value should be raised. Thirty pounds corresponds to the weight of a
50th percentile 3-year-old, and to the weight of a 95th percentile
18-month-old; i.e., children too small to be safely protected in a
booster seat. In the November 2, 2020 NPRM, NHTSA proposed to amend
S5.5.2(f) to raise the 13.6 kg (30 lb) limit to 18.2 kg (40 lb),
which is greater than the weight of a 97th percentile 3-year-old
(17.7 kg (39.3 lb)) and approximately the weight of an 85th
percentile 4-year-old.
---------------------------------------------------------------------------

Estimated Benefits and Costs

    NHTSA estimates that this final rule will reduce 3.7 fatalities and
41 (40.9) non-fatal injuries (MAIS \28\ 1-5) annually (see Table 1
below).\29\ The equivalent lives and the monetized benefits were
estimated in accordance with guidance issued in March 2021 by the
Office of the Secretary \30\ regarding the treatment of value of a
statistical life in regulatory analyses. This final rule is estimated
to save 15.1 equivalent lives annually. The monetized annual benefits
of this final rule at 3 and 7 percent discount rates are $169.0 million
and $152.2 million, respectively (Table 2). NHTSA estimates that the
annual cost of this final rule is approximately $7.37 million. The
countermeasures may include larger wings and padding with energy
absorption characteristics that cost, on average, approximately $0.58
per CRS designed for children in a weight range that includes weights
up to 40 lb (both forward-facing and rear-facing) (Table 3 below). The
annual net benefits are estimated to be $144.8 million (7 percent
discount rate) to $161.6 million (3 percent discount rate) as shown in
Table 4. Because this final rule is cost beneficial just by comparing
costs to monetized economic benefits, and there is a net benefit, NHTSA
has not provided a net cost per equivalent life saved as there is no
additional value provided by such an estimate.
---------------------------------------------------------------------------

    \28\ MAIS (Maximum Abbreviated Injury Scale) represents the
maximum injury severity of an occupant based on the Abbreviated
Injury Scale (AIS). AIS ranks individual injuries by body region on
a scale of 1 to 6: 1 = minor, 2 = moderate, 3 = serious, 4 = severe,
5 = critical, and 6 = maximum (untreatable). MAIS 3 + injuries
represent MAIS injuries at an AIS level of 3, 4, 5, or 6.
    \29\ NHTSA has developed a Final Regulatory Impact Analysis
(FRIA) that discusses issues relating to the potential costs,
benefits, and other impacts of this regulatory action. The FRIA is
available in the docket for this final rule and may be obtained by
downloading it or by contacting Docket Management at the address or
telephone number provided at the beginning of this document.
    \30\ https://www.transportation.gov/office-policy/transportation-policy/revised-departmental-guidance-on-valuation-of-a-statistical-life-in-economic-analysis.

                   Table 1--Annual Estimated Benefits
------------------------------------------------------------------------

------------------------------------------------------------------------
Fatalities..............................................             3.7
Non-fatal injuries (MAIS 1 to 5)........................       41 (40.9)
------------------------------------------------------------------------

                                      Table 2--Estimated Monetized Benefits
                                          [In millions of 2020 dollars]
----------------------------------------------------------------------------------------------------------------
                                                                                Value of
                                                                     Economic       statistical   Total benefits
                                                                     benefits          life
----------------------------------------------------------------------------------------------------------------
3 Percent Discount Rate.........................................          $26.24         $142.72         $168.97
7 Percent Discount Rate.........................................           23.63          128.53          152.16
----------------------------------------------------------------------------------------------------------------

                        Table 3--Estimated Costs
                            [2020 Economics]
------------------------------------------------------------------------

------------------------------------------------------------------------
Average cost per CRS designed for          $0.58.
 children in a weight range that includes
 weights up to 40 lb.
                                          ------------------------------
  Total annual cost......................  7.37 million.
------------------------------------------------------------------------

                                     Table 4--Annualized Costs and Benefits
                                          [In millions of 2020 dollars]
----------------------------------------------------------------------------------------------------------------
                                                                    Annualized      Annualized
                                                                       costs         benefits      Net benefits
----------------------------------------------------------------------------------------------------------------
3% Discount Rate................................................           $7.37         $168.97         $161.60
7% Discount Rate................................................            7.37          152.16          144.79
----------------------------------------------------------------------------------------------------------------

How This Final Rule Differs From the NPRM

    For the convenience of the reader, the notable changes from the
NPRM are described below. They are explained in detail in relevant
sections throughout this preamble. More minor changes (e.g.,
positioning the arm of the Q3s) are not highlighted below but are
discussed in the sections of this preamble relating to the topic.
     The side impact seat assembly (SISA) specified in this
final rule is slightly different from the proposed

SISA in four ways: aspects of the representative vehicle seat cushion
(characteristics of the seat foam), the height of the seat back,
location of the child restraint anchorages and seat belts, and vertical
position of the door and armrest. These changes were made to make it
easier to source foam, and to reflect real-world vehicle seats more
accurately. The changes align with the November 2, 2020 NPRM that
proposes to update FMVSS No. 213's frontal impact test seat
assembly.\31\ Stiffening structures were also added to the sliding seat
to minimize vibrations in compliance testing.
---------------------------------------------------------------------------

    \31\ 85 FR 69388, supra.
---------------------------------------------------------------------------

     The tolerance in the relative velocity (V0)
between the sliding seat and the door assembly at time of initial
contact (T0) is reduced in the final rule from the proposed
31.3  0.8 km/h to 31.3  0.64 km/h to improve
repeatability and reproducibility of the test.
     The NPRM proposed that the test platform velocity during
the time of interaction of the door with the CRS would be no greater
than V0 and not less than V0-1 km/h. This final
rule specifies the test platform velocity as no lower than 2.5 km/h
less than its velocity at time = T0. This change provides
more flexibility to different test facilities to meet the test
specifications while maintaining satisfactory test repeatability and
reproducibility.
     This final rule includes specifications for a relative
door velocity corridor (the velocity of the simulated door assembly
relative to the sliding seat) to improve the repeatability and
reproducibility of the test procedure. NHTSA requested comment in the
NPRM on the merits of a corridor and decided, after reviewing the
comments, that a corridor increases the repeatability and
reproducibility of the test when different types of sled systems \32\
are used.
---------------------------------------------------------------------------

    \32\ There are acceleration and deceleration type sled systems.
An acceleration sled is accelerated from rest to a prescribed
acceleration profile to simulate the occupant compartment
deceleration in a crash event. In comparison, a deceleration sled is
first accelerated to a target velocity and then is decelerated to a
prescribed deceleration profile to simulate the same event.
---------------------------------------------------------------------------

     NHTSA tentatively believed in the NPRM that CRS
performance would not be affected if a CRS were attached to the SISA by
a seat belt or by the child restraint anchorage system, assuming that a
seat belt would be routed through a belt path near to where the
anchorage attachment points are located. NHTSA thus proposed to test
child restraints by attaching them only by the child restraint
anchorage system, and requested comment on the issue. Several
commenters supported testing with the seat belt attachment in addition
to the child restraint anchorage system attachment. After considering
the comments, and after observing that some newer child restraint
designs have belt paths no longer near the CRS's anchorage attachment
points, NHTSA has included a test configuration using a Type 2 seat
belt (lap and shoulder belt) with the CRS's top tether attached, if
provided.
     The NPRM proposed using the 12-month-old CRABI dummy to
test child restraints recommended for children weighing 5 to 10 kg (11
to 22 lb) and the Q3s dummy (representative of a 3-year-old child) to
test child restraints for children weighing 10 to 18.1 kg (22 to 40
lb). After reviewing comments on this issue, NHTSA has decided to raise
the 10 kg (22 lb) dividing line to 13.6 kg (30 lb) so that infant
carriers would not be subject to testing with the Q3s 3-year-old
dummy.\33\ Testing with the Q3s does not make sense as the dummy is too
large to fit an infant carrier and is not representative of the
children for whom the restraint is recommended. Testing infant carriers
with only the CRABI 12-month-old dummy better aligns the standard's
test requirements with real world use of the restraints.\34\
---------------------------------------------------------------------------

    \33\ An infant carrier is a rear-facing CRS designed to be
easily used inside and outside of the vehicle. They typically are
sold for use by children in a weight range from newborn to 18.5 kg
(40 lb). An infant carrier is designed to be easily removed from the
vehicle and has a carrying handle that allows caregivers to tote the
infant outside of the vehicle without having to remove the child
from the restraint system. Some come with a base that stays inside
the vehicle, enabling a simple means of reattaching the carrier when
it is used as a CRS. This change is consistent with the November 2,
2020 NPRM on FMVSS No. 213's frontal crash test requirements.
    \34\ This statement assumes the carriers are not designed to
accommodate child weights over 13.6 kg (30 lb).
---------------------------------------------------------------------------

II. Safety Need

    The motor vehicle occupant fatality rate among children 3-years-old
\35\ and younger has declined from 4.5 in 1975 to 1.1 in 2019 (per
100,000 occupants). This decline in fatality rate is partially
attributed to the increased use of child restraint systems. The 2019
National Survey of the Use of Booster Seats (NSUBS) found that
restraint use in the rear row (excluding third or further rows) was 98
percent for children less than 1-year-old, 95 percent for 1- to 3-year-
old, and 88 percent for 4- to 7-year-old.\36\
---------------------------------------------------------------------------

    \35\ As used in this document, ``children 3-years-old and
younger'' includes children up to the day before they turn 4-years-
old.
    \36\ Enriquez, J. (2021, May). The 2019 National Survey of the
Use of Booster Seats (Report No. DOT HS 813 033). National Highway
Traffic Safety Administration. https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/813033.
---------------------------------------------------------------------------

    According to the 2019 FARS data files, there were 36,096 persons
killed in motor vehicle crashes in 2019, 177 of whom were children aged
3 and younger killed in passenger vehicle crashes. Among the 177 child
occupant fatalities, 44 (25 percent) were unrestrained, 7 (4 percent)
were restrained by vehicle seat belts, 111 (63 percent) were restrained
in CRSs, and 13 (7 percent) had unknown restraint use.\37\
---------------------------------------------------------------------------

    \37\ Children, Traffic Safety Facts--2009 data, DOT HS 811 387,
NHTSA, https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/811387.
---------------------------------------------------------------------------

    In 1996, the agency estimated the effectiveness of CRSs and found
the devices to reduce fatalities by 71 percent for children younger
than 1-year-old and by 54 percent for toddlers 1- to 4-years-old in
passenger vehicles.\38\ For this rulemaking, the agency updated the
1996 effectiveness estimates by conducting a similar analysis using the
FARS data files for the years 1995-2009.\39\ In the updated
analysis,\40\ only non-rollover frontal and side crashes of passenger
cars and LTVs were considered. CRS effectiveness was estimated for each
crash mode. Due to small sample size of unrestrained children less than
1-year-old, the 0- to 1-year-old age group was combined with the 1- to
3-year-old age group for determining CRS effectiveness for each crash
mode. The results indicate that in non-rollover frontal crashes, CRSs
currently in use are 53 percent effective in preventing fatalities
among children 0- to 3-years-old and 43 percent effective among
children 4- to 7-years-old. In non-rollover side crashes, CRSs
currently in use are 42 percent effective in preventing fatalities
among 0- to 3-year-old children and 51 percent effective among 4- to 7-
year-old children.
---------------------------------------------------------------------------

    \38\ ``Revised Estimates of Child Restraint Effectiveness,''
Research Note, supra.
    \39\ Details of the analysis method are provided in the
supporting technical document in the docket for the NPRM.
    \40\ Details of the updated analysis are provided in the
supporting technical document in the docket for the NPRM.
---------------------------------------------------------------------------

    NHTSA estimates that the lives of 325 children 3-years-old and
younger were saved in 2017 due to the use of child restraint
systems.\41\
---------------------------------------------------------------------------

    \41\ National Center for Statistics and Analysis (2019, March).
Lives saved in 2017 by restraint use and minimum-drinking-age laws
(Traffic Safety Facts Crash[middot]Stats. Report No. DOT HS 812
683). Washington, DC: National Highway Traffic Safety
Administration. Available at: https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/8126834.
---------------------------------------------------------------------------

    Failure to use proper occupant restraints is a significant factor
in a large

number of child occupant fatalities resulting from motor vehicle
crashes. In addition, fatalities among children properly restrained in
child restraints are often attributed to the severity of the crash.
Sherwood \42\ examined the FARS database for the year 2000 and
determined that there were 621 child occupant fatalities in the age
range of 0 to 5 years. Among these 621 fatalities, 143 (23 percent)
children were reported to be in child restraints. Detailed police
reports were available for 92 of the 143 fatally injured children
restrained in CRSs. Sherwood examined these 92 police reports and
determined that half of the 92 fatalities were in un-survivable
crashes, 12 percent of the fatalities were judged to result from gross
misuse of child restraints, 16 percent in non-catastrophic side
impacts, and 13 percent in non-catastrophic frontal impacts. Sherwood
noted that side impacts accounted for the largest number of fatalities
(40 percent), and in all side impact crashes involving child
fatalities, there was vehicle intrusion at the child's seating
position.
---------------------------------------------------------------------------

    \42\ Sherwood, C.P., Ferguson, S.A., Crandall, J.R., ``Factors
Leading to Crash Fatalities to Children in Child Restraints,'' 47th
Annual Proceedings of the Association for the Advancement of
Automotive Medicine (AAAM), September 2003.
---------------------------------------------------------------------------

In-Depth Study of Fatalities Among Child Occupants

    The agency further examined the real-world crash databases managed
by the agency (FARS (2015-2019) and the National Automotive Sampling
System-Crashworthiness Data System (NASS-CDS) 2001-2015) to better
understand fatalities to children restrained in child restraints when
involved in side crashes.
    First, NHTSA categorized the crash cases involving children (0- to
12-years-old) seated in rear seating positions, by restraint use, crash
type, and child age. See Tables 5 and 6, below.

  Table 5--Average Annual Crash Fatalities Among Children 0- to 12-Years-Old in Rear Seating Positions of Light
                            Passenger Vehicles Categorized by Restraint Type and Age
                                                [FARS 2015-2019]
----------------------------------------------------------------------------------------------------------------
                                                            Age (years)
            Restraint            ----------------------------------------------------------------      Total
                                      Under 1           1-3             4-7            8-12
----------------------------------------------------------------------------------------------------------------
None............................             7.2            24.6            50.6            67.0           149.4
Adult Belt......................             0.8             8.2            36.8            77.0           122.8
CRS.............................            40.6            96.6            69.2             6.4           212.8
Unknown.........................             3.2             9.4            15.0            12.4            40.0
Other...........................             0.0             0.2             0.6             0.4             1.2
                                 -------------------------------------------------------------------------------
    Total.......................            51.8           139.0           172.2           163.2           526.2
----------------------------------------------------------------------------------------------------------------

    Annually on average between 2015 and 2019, there were 526 crash
fatalities among children 0- to 12-years-old seated in rear seating
positions of light vehicles. Among these fatalities, on average 213 (40
percent) were children restrained in CRSs (137 were 0- to 3-years-old
and 76 were 4- to 12-years-old). Nearly 64 percent of the CRS
restrained child fatalities were children 0- to 3-years-old.
    As shown in the last column of Table 6, among the 213 fatalities of
children 0- to 12-years-old restrained in rear seats of light passenger
vehicles and in CRSs, approximately 31 percent occurred in frontal
crashes, 25 percent in side crashes, 22 percent in rollovers, and 19
percent in rear crashes. Approximately 55 percent of side impact
fatalities (28.8/52.2) were in near-side impacts. (``Far-side''
position means the outboard seating position on the opposite side of
the point of impact or the center seating position.)
---------------------------------------------------------------------------

    \43\ The 2005-2009 FARS analysis presented in the NPRM, showed
31 percent fatalities of children 0- to 12-years-old restrained in
rear seats of light passenger vehicles and in CRSs were in side
impact. The 2015-2019 FARS analysis shows only 24.5 percent of
fatalities in side impacts, however, the difference in the figures
are attributed to the changing available variables in FARS not a
decrease in side impact fatalities. The 2005-2009 FARS analysis was
done using ``IMPACT2 (most damaged area)'' while the 2015-2019 was
done using ``IMPACT1 (area of initial contact), as IMPACT2 was
retired.

 Table 6--Average Annual Crash Fatalities Among Children 0- to 12-Years-Old in Rear Seating Positions of Light Passenger Vehicles and Restrained in CRSs
                                                                  by Crash Mode and Age
                                                                  [FARS 2015-2019] \43\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Age (years)
                       Crash mode                        ----------------------------------------------------------------      Total      Percent  total
                                                                <1              1-3             4-7            8-12
--------------------------------------------------------------------------------------------------------------------------------------------------------
Rollover................................................             8.0            21.8            15.4             1.6            46.8            22.0
Front...................................................            13.6            30.8            21.4             0.8            66.6            31.3
Side....................................................            10.2            23.4            16.2             2.4            52.2            24.5
Near-side...............................................             6.2            11.6             9.2             1.8            28.8            13.5
Far-side................................................             3.8            11.4             6.8             0.6            22.6            10.6
Unknown-side............................................             0.2             0.4             0.2             0.0             0.8             0.4
Rear....................................................             7.8            17.0            14.0             1.6            40.4            19.0
Other...................................................             0.4             2.0             1.0             0.0             3.4             1.6
Unknown.................................................             0.6             1.6             1.2             0.0             3.4             1.6
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................            40.6            96.6            69.2             6.4           212.8           100.0
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Of the side impact crash fatalities among CRS restrained children
0- to 12-years-old in rear seating positions, nearly 62 percent of near
side fatalities ((6.2 + 11.6)/28.8) were to children under the age of
4.

In-Depth Study of Injuries to Child Occupants in Motor Vehicle Crashes

    In 2010, the agency published an analysis of the NASS--General
Estimates System (GES) data for the years 1999-2008 to better
understand injuries to children in motor vehicle traffic crashes.\44\
The analysis was conducted for three different child age groups (<1-
year-old, 1- to 3-years-old, and 4- to 7-years-old) and for different
crash modes (rollover, front, side, and rear). The analysis indicated
that CRSs are effective in reducing incapacitating injuries in all
three child age groups examined and in all four crash modes. The
analysis found that rollover crashes accounted for the highest rate of
incapacitating injuries, with the incidence rate among unrestrained
children (26 percent) being nearly 3 times that for children restrained
in CRSs (9 percent). In near-side impact crashes, unrestrained children
(incidence rate = 8 percent) were 8 times more likely to sustain
incapacitating injuries than children in CRSs (incidence rate = 1
percent).
---------------------------------------------------------------------------

    \44\ Hanna, R., ``Children Injured in Motor Vehicle Traffic
Crashes,'' DOT HS 811 325, NHTSA, May 2010, http://www-nrd.nhtsa.dot.gov/Pubs/811325.pdf, last accessed on July 2, 2012.
---------------------------------------------------------------------------

    The agency analyzed NASS-CDS for the years 2001-2015 to obtain
annual estimates of moderate or higher severity injuries (MAIS 2+
injuries) among children of different ages in different restraint
environment and crash modes. See Table 7 and 8.

Table 7--Average Annual Estimates of 0- to 12-Years-Old Children With MAIS 2+ Injuries in Rear Seating Positions of Light Passenger Vehicles Involved in
                                                         Motor Vehicle Crashes by Restraint Type
                                                                  [NASS-CDS 2001-2015]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Age (years)
                        Restraint                        ----------------------------------------------------------------      Total        Percent of
                                                              Under 1           1-3             4-7            8-12                            total
--------------------------------------------------------------------------------------------------------------------------------------------------------
None....................................................              15              94             530             575           1,214            20.0
Adult Belt..............................................               0              91             489             860           1,440            23.8
CRS.....................................................             181             731             504              36           1,452            24.0
Unknown if Used.........................................               1              28             323             146             498             8.2
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................             378           1,675           2,350           1,653           6,056           100.0
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Between 2001 and 2015 on average annually there were an estimated
6,056 twelve and younger children with MAIS 2 + injuries seated in the
rear seats of light passenger vehicles with 2,053 of these injured
occupants being younger than 4- years-old. Approximately 1,452 CRS
restrained children 12-years-old and younger sustained MAIS 2+injuries,
among which 912 (63 percent) were children younger than 4-years-old and
504 (35 percent) were 4- to 7-year-old children.
    The NASS-CDS 2001-2015 data files were further analyzed to
determine crash characteristics. Table 8 presents the average annual
estimates of 0- to 12-year-old children with MAIS 2+ injuries in rear
seating positions of light passenger vehicles. Approximately 38 percent
of the children were injured in frontal crashes, 32 percent in side
crashes, 24 percent in rollover crashes and 5 percent in rear crashes.

Table 8--Average Annual Estimates of 0- to 12-Years-Old Children With MAIS 2+ Injuries in Rear Seating Positions of Light Passenger Vehicles Involved in
                                                           Motor Vehicle Crashes by Crash Mode
                                                                  [NASS-CDS 2001-2015]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Age (years)
                       Crash mode                        ----------------------------------------------------------------      Total        Percent of
                                                                <1              1-3             4-7            8-12                            total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Rollover................................................              13             150             396             543           1,102            23.9
Front...................................................              62             329             710             658           1,759            38.2
Side....................................................              46             373             691             387           1,497            32.5
    Near-Side...........................................              31             276             330             260             897            19.5
    Far-Side............................................              11              58             360             126             555            12.1
    Unknown-Side........................................               4              39               1               1              45             1.0
Rear....................................................              78              76              49              29             232             5.0
Other...................................................               0              14               0               0              14             0.3
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................             199             942           1,846           1,617           4,604           100.0
--------------------------------------------------------------------------------------------------------------------------------------------------------

    To better understand the crash characteristics of children
restrained in child restraints, a similar analysis as that shown in
Table 8 was conducted except that only the cases where the children
were restrained in CRSs were included in the analysis. The results are
presented in Table 9.

   Table 9--Average Annual Estimates of 0- to 12-Years-Old CRS Restrained Children With MAIS 2+ Injuries in Rear Seating Positions of Light Passenger
                                                Vehicles Involved in Motor Vehicle Crashes by Crash Mode
                                                                  [NASS-CDS 2001-2015]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Age (years)
                       Crash mode                        ----------------------------------------------------------------      Total        Percent of
                                                              Under 1           1-3             4-7            8-12                            total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Rollover................................................              12              60             102               0             174            12.0
Front...................................................              55             293             233              18             599            41.2
Side....................................................              42             323             139              18             522            35.9
    Near-side...........................................              31             272              44              18             336            25.1
    Far-side............................................              11              51              95               0             157            10.8
Rear....................................................              74              54              31               0             159           10.29
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................             183             730             505              36           1,454           100.0
--------------------------------------------------------------------------------------------------------------------------------------------------------

    For MAIS 2+ injured 12-years-old and younger child occupants in
passenger vehicles restrained in CRSs in rear seating positions, 41
percent of the injuries were in frontal crashes, 36 percent in side
crashes, 12 percent in rollovers, and 10 percent in rear crashes. About
64 percent (336/522) of the occupants in side crashes were in near-side
impacts.
    In the above analyses, some of these injuries and fatalities
involved children in seats that were incorrectly used. However, NHTSA
does not have complete data on the number accidents that involved
misuse because accident databases do not generally collect data on how
child restraints were used.

III. Statutory Mandate

    Subtitle E of the ``Moving Ahead for Progress in the 21st Century
Act'' (MAP-21), Public Law 112-141 (July 6, 2012),\45\ included Section
31501(a), which stated that, not later than two years after the date of
enactment of the Act, the Secretary (NHTSA by delegation) shall issue a
final rule amending Federal Motor Vehicle Safety Standard No. 213 to
improve the protection of children seated in child restraint systems
during side impact crashes.
---------------------------------------------------------------------------

    \45\ Subtitle E is entitled ``Child Safety Standards.''
---------------------------------------------------------------------------

    This final rule accords with MAP-21 and implements Congress's
intent to implement a side impact standard for child restraints. In
2004, NHTSA informed Congress \46\ that, while enhanced side impact
protection for children in child restraints was a priority for NHTSA,
NHTSA had initiated a side impact rulemaking in response to the
Transportation Recall Enhancement, Accountability and Documentation
(TREAD) Act but found the extent of the uncertainties prevented
adoption of a side impact performance test for CRSs.\47\ NHTSA informed
Congress when the agency withdrew the rulemaking that NHTSA would
continue its efforts to obtain detailed side crash data identifying
specific injury mechanisms involving children and would work toward
developing countermeasures using test dummies, including the European
Q3 dummy then available, for improved side impact protection.
---------------------------------------------------------------------------

    \46\ NHTSA Report to Congress, ``Child Restraint Systems,
Transportation Recall Enhancement, Accountability, and Documentation
Act,'' February 2004. www.nhtsa.gov/nhtsa/announce/NHTSAReports/TREAD.pdf.
    \47\ Advance Notice of Proposed Rulemaking, 67 FR 21836, May 1,
2002.
---------------------------------------------------------------------------

    In March 2011, NHTSA's Vehicle Safety and Fuel Economy Rulemaking
and Research Priority Plan 2011-2013, announced the agency's intention
to issue an NPRM in 2012 on child restraint side impact protection.\48\
NHTSA stated in the plan that it was planning to ``[p]ropose test
procedures in FMVSS No. 213 to assess child restraint performance in
near-side impacts. Amend Part 572 to add the Q3s dummy, the 3-year-old
side impact version of the Q-series of child dummies.''
---------------------------------------------------------------------------

    \48\ Docket No. NHTSA-2009-0108-0032.
---------------------------------------------------------------------------

    MAP-21 was enacted soon thereafter, with a short deadline for
issuance of a final rule. Given the context of NHTSA's work in this
area, NHTSA has interpreted Subtitle E as directing NHTSA to apply the
knowledge gained since its 2004 report to Congress to initiate and
complete the side impact regulation as the agency had planned. There
were no child test dummies other than the Q3s available when MAP-21 was
enacted that were proven sufficiently durable and reliable for use in
the FMVSS No. 213 side impact test.\49\ There was not enough time to
develop and validate a different test procedure, or new child side
impact test dummies, within the time constraints of Subtitle E.
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    \49\ There are still no child test dummies that are suitable for
use in a side impact FMVSS other than the Q3s.
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    MAP-21 required a final rule ``amending FMVSS No. 213,'' which
NHTSA has interpreted to mean that the rulemaking must be conducted in
accordance with the National Traffic and Motor Vehicle Safety Act (49
U.S.C. 30101 et seq.) (Safety Act). NHTSA has developed a standard that
will improve the protection of children seated in child restraint
systems during side impacts, in accordance with MAP-21, while meeting
the criteria of Section 30111 of the Safety Act. Standard No. 213a
meets the need for safety, is stated in objective terms, and is
reasonable, practicable, and appropriate for the CRSs for which it is
prescribed. There are technical and practical reasons for applying the
dynamic side impact test only to CRSs designed to seat children in a
weight range that includes weights up to 18.1 kg (40 lb).
    For one, there is no side impact dummy representative of children
weighing more than 40 lb that is proven to provide the test
measurements required of a dummy used in the Federal motor vehicle
safety standards. Without an appropriate test dummy, the data from a
dynamic test would not provide a meaningful assessment of the
performance of the CRS in protecting children of weights above 18.1 kg
(40 lb). Without a valid test dummy, CRSs for heavier children may
``pass'' a side impact test with the Q3s, but the Q3s would not
meaningfully assess the performance of the CRS in protecting the
heavier child. Raising the limit above 40 lb could engender a false
sense of security that a restraint adequately protects the heavier
children when, in fact, without a heavier test dummy, the standard
would not be adequately assessing the restraint's protection of these
children. NHTSA believes Congress was aware of this limitation on the
availability of test dummies when it enacted MAP-21, and did not want

NHTSA to apply the new standard to a subset of CRSs that could not be
sufficiently assessed for their performance in protecting a child in a
side impact. Moreover, it does not seem sensible to require
manufacturers to ensure their CRSs comply with the standard tested with
the Q3s if the child restraints are not intended for, and will not be
used with, children of the size represented by the Q3s. Thus, NHTSA
does not consider it reasonable or appropriate \50\ to apply this final
rule to child restraints that are not recommended for children weighing
between 13.6 kg (30 lb) and 18.1 kg (40 lb).
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    \50\ 49 U.S.C. 30111(b)(3).
---------------------------------------------------------------------------

    In addition, NHTSA drafted this final rule recognizing that
children weighing more than 18.1 kg (40 lb) seated in a child restraint
will be seated high enough to benefit from a passenger vehicle's side
curtain air bags.\51\ In the November 2, 2020 NPRM proposing to amend
FMVSS No. 213, supra, NHTSA proposed requiring booster seats to be
labeled only for children weighing more than 18.1 kg (40 lb). If,
because of that label, children are kept in safety seats until they are
at least 18.1 kg (40 lb), they will be seated until that time in a CRS
that will be certified to the side impact protection requirements of
FMVSS No. 213a. Also, when they transition to a booster seat (or a
child restraint with an internal harness intended for children weighing
more than 18.1 kg (40 lb)), such booster seat or child restraint will
lift them high enough to be protected by the vehicle's side curtain air
bags. That label will help ensure that children will remain in car
seats longer and will only use booster seats when they are tall enough
to take advantage of a vehicle's side protection countermeasures.
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    \51\ Children weighing more than 18.1 kg (40 lb) restrained in
CRSs would have a seated height similar to the height of a 5th
percentile adult female. The vehicle's side curtain air bags are
designed to protect occupants, including those of the size of a 5th
percentile female, in side impacts and rollovers.
---------------------------------------------------------------------------

IV. Guiding Principles

    In addition to the considerations already discussed, the following
principles also guided NHTSA's decisions in developing this final rule.
    1. There is a safety need for this rulemaking notwithstanding the
estimated effectiveness of child restraints in side impacts.\52\ Child
restraint safety in side impacts can be increased. NHTSA has observed
that increasing numbers of CRSs appear to have more side structure
coverage (CRS side ``wings'') and side padding than before.\53\ Because
the design of the side wings and stiffness of the padding are factors
that affect the containment of the child dummy and the injury measures,
NHTSA considers the side wing coverage and increased padding to be
overall positive developments. However, because FMVSS No. 213 did not
have a side impact test, a quantifiable assessment of the protective
qualities of the features was heretofore not possible. Further, testing
NHTSA conducted in developing this final rule indicate that not all
side wings and padding protect the same, and in some cases, ``more'' of
a countermeasure (padding, structure) was not necessarily ``better.''
This final rule establishes performance requirements that ensure that
the wings, padding, padding-like features, or other countermeasures
employed to provide protection in side impacts will be engineered to
attain at least a minimum threshold of performance that will reduce
unreasonable risk of injury or fatality in side impacts. For CRS
designs that have not yet incorporated side impact protection features,
this final rule ensures they will.
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    \52\ NHTSA estimates that CRSs are already 42 percent effective
in preventing death in side crashes of 0- to 3-year-old children.
Supra.
    \53\ SafetyBeltSafe U.S.A. https://web.archive.org/web/20131012130527/http://www.carseat.org/Pictorial/InfantPict,1-11.pdf
and https://web.archive.org/web/20120915194832/http://www.carseat.org/Pictorial/3-Five-%20Point-np.pdf.
---------------------------------------------------------------------------

    2. In making regulatory decisions on possible enhancements to CRS
performance, NHTSA bears in mind the consumer acceptance of cost
increases to a highly effective item of safety equipment.\54\ Any
enhancement that would significantly raise the price of the restraints
could potentially have an adverse effect on the sales and use of this
equipment. The net effect on safety could be negative if the effect of
sales losses exceeds the benefit of the improved performance of the
restraints that are purchased, or if older child restraints that are
not designed to meet current requirements were reused. Thus, to
maximize the total safety benefits of its efforts on FMVSS No. 213,
NHTSA must balance those improvements against impacts on the price of
restraints. In addition, NHTSA must also consider the effects of
improved performance on the ease of using child restraints. If the use
of child restraints becomes overly complex or unwieldy, the misuse and
nonuse of child restraints could increase, and the benefits engineered
into the CRS not realized in the real world.
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    \54\ Child restraint systems are highly effective in reducing
the likelihood of death or serious injury in motor vehicle crashes.
NHTSA estimates that, for children less than 1-year-old, a child
restraint can reduce the risk of fatality by 71 percent when used in
a passenger car and by 58 percent when used in a pickup truck, van,
or sport utility vehicle (light truck). ``Revised Estimates of Child
Restraint Effectiveness,'' Research Note, National Center for
Statistics and Analysis (NCSA) of the National Highway Traffic
Safety Administration (NHTSA), DOT HS 96855, December 1996. Child
restraint effectiveness for children between the ages 1- to 4-years-
old is 54 percent in passenger cars and 59 percent in light trucks.
Id.
---------------------------------------------------------------------------

    3. NHTSA is guided by the principles for regulatory decision-making
set forth in Executive Order (E.O.) 12866, ``Regulatory Planning and
Review,'' and E.O. 13563, ``Improving Regulation and Regulatory
Review.'' NHTSA's assessment of the net effect on safety of this
rulemaking was limited in some respects, however. Data are sparse on
side crashes resulting in severe injuries or fatalities to children in
CRSs. Data indicate that side crashes resulting in fatalities to
children in CRSs mainly occur in very severe, un-survivable side impact
conditions. A dynamic test involving a very high velocity impact may
not be reasonable if ultimately the crash replicated were basically un-
survivable, or if the standard's requirements were impracticable or
resulted in CRSs that could not be used as a practical matter or used
correctly. Another limiting factor was the absence of information
comparing the real-world performance of ``good'' performing CRSs versus
``poor'' performing CRSs. Without these data, NHTSA had to use test
data and injury curves to determine the effectiveness of possible
countermeasures (e.g., side wings with strategically-placed energy-
absorbing padding).

V. Overview of the NPRM and Comments Received

a. Overview of the NPRM

    NHTSA published the NPRM for this final rule on January 28, 2014
(79 FR 4570, Docket No. NHTSA-2014-0012). The NPRM proposed to amend
FMVSS No. 213 to require CRSs designed to seat children in a weight
range that includes weights up to 18.1 kg (40 lb) to meet side impact
performance requirements in new FMVSS No. 213a, in addition to the
requirements for frontal protection established in FMVSS No. 213.\55\
We

reopened the comment period on June 4, 2014, in response to a petition
from the Juvenile Products Manufacturers Association (JPMA).\56\
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    \55\ NHTSA considered incorporating the side impact requirements
into FMVSS No. 213, rather than in FMVSS No. 213a, but decided
against doing so. MAP-21 directed NHTSA to undertake side and
frontal impact test rulemakings in the same timeframe, with each
involving different compliance schedules and different test dummies.
NHTSA decided that combining the side and frontal test rulemakings
into one standard (with each encompassing entirely new sled test
systems and dynamic test requirements), could have made the
revisions difficult to understand, particularly with the new
requirements for the frontal and side tests becoming effective on
different dates. The agency decided to establish the side impact
requirements separately in FMVSS No. 213a for clarity and plain
language purposes.
    \56\ The comment period was reopened until October 2, 2014 (79
FR 32211). JPMA petitioned to provide more time for child restraint
manufacturers to obtain the Q3s dummy from the dummy manufacturer,
arrange with test labs to evaluate their CRSs with it, conduct
testing, and comment on the proposal.
---------------------------------------------------------------------------

    NHTSA proposed performance requirements that child restraints must
meet when tested dynamically in a sled test replicating a side crash.
The NPRM proposed that child restraints would be tested while attached
to a standardized seat assembly. The sled test \57\ procedure was
designed to replicate a two-vehicle side crash depicted in the moving
deformable barrier (MDB) test of FMVSS No. 214 (striking vehicle
traveling at 48.3 km/h (30 mph)) impacting the struck vehicle traveling
at 24.1 km/h (15 mph). The proposed sled test simulated a near-side
side impact of a small passenger car. FMVSS No. 213a's side impact test
represents a crash with a change of velocity of approximately 19 mph.
NHTSA's analysis of field data (NASS-CDS 1995-2009) found that 92
percent of near-side crashes for restrained children (0- to 12-years-
old) involved a change in velocity of 19 mph or lower.\58\
---------------------------------------------------------------------------

    \57\ The sled test was based on an acceleration sled system. An
acceleration sled is accelerated from rest to a prescribed
acceleration profile to simulate the occupant compartment
deceleration in a crash event. In comparison, a ``deceleration
sled'' is first accelerated to a target velocity and then is
decelerated to a prescribed deceleration profile to simulate the
same event. The proposed acceleration sled was originally developed
by the Takata Corporation. (Literature on development of the FMVSS
No. 213a sled test sometimes refers to the sled as the ``Takata''
system.)
    \58\ Obtained from an analysis of the National Automotive
Sampling System--Crashworthiness Data System (NASS-CDS) data files
for the years 1995-2009 for restrained children 0- to 12-years-old
in all restraint environments including seat belts and CRS. Details
of the analysis are provided in the technical report in the docket
for the NPRM (Docket No. NHTSA-2014-0012).
---------------------------------------------------------------------------

    NHTSA examined data from FMVSS No. 214 MDB compliance tests to
identify kinematic characteristics of the vehicle test to replicate in
the sled test environment, and proposed characteristics relating to the
acceleration profile of the sliding seat (representing the struck
vehicle acceleration), the door velocity at time of contact with the
sliding seat (to represent the struck vehicle door velocity), and the
impact angle of the door with the sliding seat (to replicate the
longitudinal component of the direction of force). Comments were
requested \59\ on whether a relative door velocity profile (the
velocity of the door relative to the sliding seat) should be specified
to improve the reproducibility of the test procedure using different
types of sled systems.
---------------------------------------------------------------------------

    \59\ 79 FR at 4585.
---------------------------------------------------------------------------

    NHTSA proposed to apply FMVSS No. 213a to CRSs manufactured and
offered for sale for children up to 18.1 kg (40 lb). The NPRM proposed
that child restraint systems with integral internal harnesses (car
seats or safety seats) would be attached to the side impact seat
assembly (SISA) using the child restraint anchorage system on the SISA
(including the top tether, if one were provided).\60\ Comments were
requested on whether car seats should also be tested when attached by a
Type 2 belt and top tether. The NPRM proposed that child restraints
that do not have connectors designed to attach to a child restraint
anchorage system would be tested using a Type 2 belt (e.g., booster
seats recommended for children weighing less than 18.1 kg (40 lb)
\61\).
---------------------------------------------------------------------------

    \60\ The child restraint anchorage system is commonly referred
to as the LATCH system (``Lower Anchors and Tethers for Children'').
    \61\ This proposal predated a November 2, 2020 NPRM in which
NHTSA proposed prohibiting booster seats from being recommended for
children weighing less than 18.1 kg (40 lb). If the November 2020
proposal is adopted, the FMVSS No. 213a provision would be moot.
---------------------------------------------------------------------------

    NHTSA proposed that child restraint systems recommended for
children with weights in the 10 kg to 18.1 kg (22 lb to 40 lb) range
would be tested on the SISA with the Q3s test dummy.\62\ Child
restraints would have to meet injury criteria (expressed in terms of
HIC15 \63\ and chest deflection) when tested with the Q3s dummy. These
criteria allow a quantitative evaluation of the effectiveness of the
CRS, and the ability of the CRS to prevent or attenuate head and chest
impact with the intruding door. CRSs recommended for children with
weights that include weights up to 10 kg (22 lb) would be tested with
the 12-month-old CRABI dummy (49 CFR part 572, subpart R). Because the
CRABI dummy is designed for frontal and not side impacts, the NPRM
proposed that the CRABI would be used only to measure the containment
capability of the child restraint (the ability of the restraint to
prevent the dummy's head from contacting the intruding door of the
SISA). The dummy's head and chest instrumentation would not be
leveraged since the dummy was not designed to assess crash forces in
side impacts.
---------------------------------------------------------------------------

    \62\ The proposed weight ranges described in this paragraph have
been adjusted in this final rule. NHTSA is adopting a 13.6 kg (30
lb) cut off instead of a 10-kg (22-lb) cut off.
    \63\ A measurement of the head injury criterion that is based on
the integration of resultant head acceleration over a 15-millisecond
duration.
---------------------------------------------------------------------------

    The NPRM also proposed requiring child restraints to meet
structural integrity and other performance requirements in FMVSS No.
213. When a CRS is dynamically tested with the appropriate ATD, there
should not be any complete separation of any load-bearing structural
element \64\ of the CRS or any partial separation exposing surfaces
with sharp edges that may contact an occupant. These requirements would
reduce the likelihood that a child using the CRS would be injured by
the collapse or disintegration of the system, projectiles coming from a
seat involved in a side crash or by contact with the interior of the
passenger compartment or with components of the CRS. NHTSA notes that
while some CRS structures have not been considered load-bearing
structural elements in frontal testing (FMVSS No. 213) by NHTSA, these
same CRS structures may be considered load-bearing structural elements
in side impact testing (FMVSS No. 213a).
---------------------------------------------------------------------------

    \64\ NHTSA interprets load bearing structure to mean a structure
that: (1) transfers energy from the SISA and/or door to the CRS
(e.g., installation components or CRS areas that contact the
intruding door), or (2) transfers energy from the CRS to the
occupant or vice versa (e.g., belts and components to restrain the
child, CRS surfaces or parts transferring energy to the occupant).
---------------------------------------------------------------------------

    Injury from contacting protrusions, such as the pointed ends of
screws mounted in padding, would be prevented in a similar manner as
that specified for the frontal crash test in FMVSS No. 213. The height
of such protrusions would be limited to not more than 0.375 inches
above any immediately adjacent surface. Also, contactable surfaces
(surfaces contacted by the head or torso of the ATD) would not be
permitted to have an edge with a radius of less than 6.35 mm (0.25
inches), even under padding. Padding will compress in an impact and the
load imposed on the child would be concentrated and potentially
injurious.
    The NPRM discussed NHTSA's testing of CRS models representative of
seats available then in the market. NHTSA had tested twelve forward-
facing and five rear-facing child restraints with the Q3s dummy. The
Q3s measured HIC15 greater than 570 in seven of the twelve forward-
facing CRSs tested. The Q3s measured chest deflection greater than 23
mm in three of the twelve forward-facing CRSs tested. The Q3s measured
both HIC15 greater than 570 and chest deflection greater than 23 mm in
three of the tests of the forward-facing CRSs. For the five

rear-facing CRSs tested with the Q3s, the results of the fleet tests
showed that the Q3s measured HIC15 greater than 570 in three of the
five rear-facing CRSs tested, and chest deflection greater than 23 mm
in two of the five tests. The Q3s measured both HIC15 greater than 570
and chest deflection greater than 23 mm in one of the five rear-facing
CRSs tested. NHTSA tested 12 rear-facing CRSs with the CRABI to
estimate the performance of the fleet. Using head-to-door contact as
the performance criterion in the fleet tests, the results showed that
the CRABI had head contact only with one child restraint (one out of
the twelve models tested).

b. Summary of the Comments

    NHTSA received 29 comments on the proposal.\65\ Commenters included
child restraint manufacturers (Dorel Juvenile Group, Graco Children's
Products, Britax Child Safety, Inc UppaBaby, Safeguard/IMMI), the
Juvenile Products Manufacturers Association (JPMA); consumer advocates
(Safe Ride News, Safe Kids Worldwide, Advocates for Highway and Auto
Safety, Consumers Union \66\); the National Transportation Safety
Board; research bodies and testing organizations (Insurance Institute
for Highway Safety (IIHS), University of Michigan Transportation
Research Institute (UMTRI), MGA Research Corporation, ARCCA, Inc., the
Transport Research Laboratory; a supplier of honeycomb (Plascore), and
members of the general public.
---------------------------------------------------------------------------

    \65\ The NPRM proposing to add the Q3s dummy specifications to
49 CFR part 572 received comments separately from the NPRM preceding
this final rule. Those comments are fully addressed in the November
3, 2020 final rule (85 FR 69898). They are discussed here to the
extent relevant to this final rule.
    \66\ Consumer Union is the Policy and Action Division of
Consumer Reports.
---------------------------------------------------------------------------

Overview of the Comments

    As summarized below, all but four commenters \67\ strongly
supported the proposed inclusion of a side impact test in FMVSS No.
213. Several commenters expressed views on the types of child
restraints they believed should be subject to FMVSS No. 213a. Many
commenters discussed technical aspects of the proposed test procedure,
such as the repeatability and reproducibility of the dynamic test, the
availability of and characteristics of the seat foam specified for the
SISA, how the tested CRS should be positioned on and attached to the
SISA, and how the Q3s should be positioned in the child restraint,
---------------------------------------------------------------------------

    \67\ These were UMTRI and three individuals.
---------------------------------------------------------------------------

    Child restraint manufacturers: All child restraint manufacturers
commenting on the NPRM supported the inclusion of a dynamic side impact
test procedure in FMVSS No. 213, as did JPMA, their industry group.
Some had questions about various issues and many responded to the
questions NHTSA had asked in the preamble to the NPRM. Dorel supported
adopting a test procedure that included an intruding door but believed
that the Q3s dummy exhibited ``artificial forward head movement before
the crash impact'' that places the dummy out of position in relation to
the side wing. Dorel expressed concerns about the repeatability and
reproducibility (R&R) of results from NHTSA's test program, as did
Graco, the latter providing feedback on results of test trials it
conducted comparing the R&R of the proposed side impact test using data
from several different test labs. Graco evaluated potential causes of
variation and recommended ways to improve the sled design to reduce
variation between the labs.
    Some CRS manufacturers suggested revisions to technical aspects of
the proposal. Britax believed the United Nations Economic Commission
for Europe Regulation No. 44 \68\ (ECE R.44) foam proposed for use on
the SISA is not readily available and specifying it in FMVSS No. 213a
may create considerable hardship from cost and availability
perspectives. Britax supported the agency's views in the NPRM about
testing and labeling of belt-positioning booster seats. UPPAbaby
recommended against using the Q3s dummy to test rear-facing infant
seats, because, it stated, ``the head of the Q3s exceeds the limit to
which we recommend a child be positioned in our seat.'' UPPAbaby
supported using a lap/shoulder belt to attach car seats to the SISA, in
addition to a child restraint anchorage system. IMMI supported
excluding harnesses from the proposed side impact requirements and
suggested ways to expand the standard's definition of a ``harness.''
JPMA reiterated Dorel's comment about ``artificial forward head
movement'' of the Q3s before impact, reported instances in which the
text in the preamble was inconsistent with proposed regulatory text,
emphasized the importance of reproducibility of test results to the
objectivity of a safety standard, and provided other information.
---------------------------------------------------------------------------

    \68\ ECE R44--Restraining Devices for Child Occupants of Power
Driven Vehicles (``Child Restraint Systems'').
---------------------------------------------------------------------------

    Consumer advocates: Safe Ride News (SRN), Safe Kids Worldwide,
Advocates for Highway & Auto Safety (Advocates), and Consumers Union
(CU) supported the proposed rule, while suggesting that NHTSA adopt
further requirements. Several commenters weighed in with responses to
the technical questions in the NPRM. Many concurred that the rule
should only apply to CRSs recommended for children weighing up to 18.1
kg (40 lb) but encouraged NHTSA to develop an ATD (anthropomorphic test
device) (test dummy) representative of older children. SRN, Safe Kids
and CU suggested lead times less than 3 years. Advocates suggested
NHTSA require various warnings on child restraints, such as a warning
on CRSs recommended for children weighing more than 40 lb that ``this
CRS has not been tested in side impacts.'' CU suggested additional
performance criteria for structural integrity and supported testing
CRSs when attached with Type 2 (lap and shoulder) belts. CU believed
that the Q3s is too large to test rear-facing infant seats, and that
NHTSA should consider a planar limit to reduce the potential for the
dummy's head to roll out of the CRS shell in some tests.
    Research and testing organizations: The Insurance Institute for
Highway Safety (IIHS) agreed with NHTSA's reasons for not applying
FMVSS No. 213a to CRSs for children weighing more than 18.1 kg (40 lb).
IIHS provided data from its belt fit program showing that children
weighing more than 18.1 kg (40 lb) seated in booster seats are likely
tall enough to benefit from the vehicle side curtain air bag. IIHS and
the University of Michigan Transportation Research Institute (UMTRI)
had concerns about possible dis-benefits from rear-facing restraints
possibly becoming wider in response to meeting FMVSS No. 213a. They
believed wider restraints could potentially indirectly increase injury
risk for restrained children, by, for example, causing older siblings
to graduate prematurely to a booster seat because wider car seats are
harder to fit side-by-side. UMTRI asked whether costs to meet the
proposed standard would be better spent on efforts to restrain
children. The commenter stated that half of pediatric fatalities from
motor vehicle crashes are to unrestrained or improperly restrained
occupants, so rather than modestly improving the side impact protection
for children, efforts should address improving the number of children
using appropriate restraints, enhancing child restraint ease-of-use,
and increasing educational efforts, such as on top tether use. ARCCA
suggested that NHTSA use the Hybrid III 6-year-old and 10-year-old

frontal crash dummies to assess head containment and structural
integrity.
    NTSB: The National Transportation Safety Board (NTSB) supported the
NPRM, believing that the proposed tests encompass the majority of CRSs
because the upper use limit for most small restraint systems extends to
at least 40 pounds and the lower use limit is at or below 40 pounds.
Nonetheless, NTSB urged NHTSA to develop suitable large-sized dummies.
NTSB expressed concern about the kinematic effects of far-side impact
crashes on larger children. NTSB also supported testing CRSs with a
seat belt attachment, in addition to the child restraint anchorage
system attachment. The commenter encouraged NHTSA to consider ease-of-
use improvements for top tethers, and use of a pure lateral
acceleration pulse in the side impact test.
    Individuals: Approximately 7 individuals commented on the NPRM.
Most of the individuals supported the proposal, with three opposing.
One of the opposing commenters argued that the injury rates for the
under 1-year-old children are nearly 4 times lower than that for the 1-
to 3-year-old children, so efforts would be better spent increasing the
number of 1- to 3-year-old children who ride rear-facing than on
adopting a side impact standard. The others believed that the estimated
benefits of the proposal are low and do not support the additional
costs to industry or to the consumer.

VI. Response to the Comments (Wide-Reaching Issues)

    NHTSA has carefully considered the comments in developing this
final rule. This section discusses the agency's decisions on matters of
general importance. Following this section are discussions relating to
specific topics, such as various technical aspects of the side impact
test procedure, the test dummies, the standard's performance criteria,
and other aspects of FMVSS No. 213a.

a. Are efforts better spent elsewhere on child seat safety?

    Almost all of the commenters supported the inclusion of a side
impact test in FMVSS No. 213, but a few expressed concerns about the
rulemaking. Dr. Alisa Baer suggested NHTSA's efforts, and those of the
industry and/or the child passenger safety community, could be better
spent on correcting misuse or nonuse of child restraints.\69\ Dr. Baer
argued that Table 9 of the NPRM showed ``the injury rates for the under
1-year-olds (presumably the majority of whom are rear-facing) are
nearly 4 times lower than for the 1-3 year-olds (presumably the
majority of whom are forward-facing).'' She stated that the benefits
seem low and may not outweigh the costs of meeting the standard--costs,
she said, that include not only material costs (such as foam) but also
research and development and crash testing costs. The commenter said
the time and money spent on ensuring CRSs comply with the standard
could be better spent elsewhere, specifically, ``at decreasing the non-
use rate, especially amongst minority and low-income populations.''
---------------------------------------------------------------------------

    \69\ Dr. Baer stated, ``[C]urrent efforts to redesign seats to
optimize protection in side impacts are misguided. I believe the
primary focus should be on increasing the number of 1-3-year-olds
who ride rear-facing as the data suggest that keeping our
preschoolers rear-facing could have a much greater impact on
reducing fatalities & injuries in restrained children than the
proposed side impact standards will.''
---------------------------------------------------------------------------

    UMTRI and IIHS expressed concern with ``possible unintended
consequences of implementing this rulemaking.'' UMTRI suggested that
only forward-facing harnessed restraints be subject to the side impact
standard, ``since children in rear-facing child restraints are already
five times safer than those in [forward-facing] restraints in side
impacts,'' citing a 2007 study by Henary et al. to support its
view.\70\ IIHS echoed this view, also citing Henary.
---------------------------------------------------------------------------

    \70\ Henary, B., Sherwood, C.P., Crandall, J.R., Kent, R.W.,
Vaca, F.E., Arbogast, K.B., Bull, M.J. (2007) ``Car safety seats for
children: rear facing for best protection.'' Injury Prevention
13:398-402. (Note: as discussed below, this article was retracted in
2016.)
---------------------------------------------------------------------------

    The commenters above also expressed concern that adding larger,
padded side structures to meet the side impact standard may increase
the overall width of child restraints and result in children
prematurely moved from rear-facing restraints to forward-facing
restraints, from harnessed car seats to boosters, and from center
seating positions to outboard positions.
Agency Response
    Increasing overall CRS use, tether use, and use of rear-facing
restraints by children above age 1 are very important goals, as each of
those measures can increase the number of child lives saved and
injuries avoided in crashes. NHTSA is actively involved in increasing
the use of CRSs and the correct use of restraint systems. These efforts
include developing and distributing training videos, producing public
safety announcements and various campaigns directed to caregivers of
children (in English and Spanish), leveraging all communication
resources (such as social media and the NHTSA website) to provide
information to parents and other caregivers, and expanding and
supporting the child passenger safety technician (CPST) curriculum used
to train and certify CRS fitting station technicians. In addition,
NHTSA's November 2, 2020 NPRM \71\ takes steps forward with proposed
changes to labeling requirements that are anticipated to result in more
children remaining rear-facing longer, and remaining in child safety
seats longer before transitioning to a booster.
---------------------------------------------------------------------------

    \71\ 85 FR 69388, supra.
---------------------------------------------------------------------------

    To be clear, however, this final rule focuses on improving the
protection provided by child restraints in side impacts and offers
expanded protection of children in a critically important crash mode--a
protection supplemental to the frontal crash protection the restraints
currently provide. Front and side crashes account for most child
occupant fatalities. MAP-21 requires NHTSA to issue a final rule to
amend FMVSS No. 213 to improve the protection of children seated in
child restraints in side impacts, but enhanced side impact protection
for children has been a priority for NHTSA before MAP-21.\72\ FMVSS No.
213a establishes a level of protection against unreasonable safety
risks in side impacts that every safety seat sold in this country will
have to provide and improves the protection afforded by the restraints
above that currently required by FMVSS No. 213. The efforts to improve
CRS use are complementary to and not inconsistent with improvements to
side crash safety, and will continue. Improved performance in side
crashes will not be achieved by improving CRS use alone, however.
Establishing FMVSS No. 213a improves the performance of child
restraints for the benefit of all children using the restraints.
---------------------------------------------------------------------------

    \72\ See NHTSA Vehicle Safety and Fuel Economy Rulemaking and
Research Priority Plan 2011-2013, March 2011, discussed in the
January 28, 2014 NPRM, supra, for this final rule (79 FR at 4572,
col. 3).
---------------------------------------------------------------------------

    NHTSA disagrees with the commenters that FMVSS No. 213a should not
apply to rear-facing child restraints. Dr. Baer may have misunderstood
Table 9 in the NPRM. Table 9 in the NPRM does not present injury rate
and instead presents average annual estimates of Abbreviated Injury
Scale (AIS) 2+ injuries.\73\ Since the population of children riding in
light vehicles is unknown, it is not possible to estimate injury rates.
The lower annual number of injuries to children

under 1 year of age could be related to fewer children of this age
group involved in crashes in comparison to 1- to 3-year-old children.
Applying FMVSS No. 213a to both front-facing and rear-facing child
restraints ensures all rear-facing child restraints will provide a
level of performance determined necessary to reduce an unreasonable
risk of death or injury in side impacts to restrained occupants.
---------------------------------------------------------------------------

    \73\ AIS ranks individual injuries by body region on a scale of
1 to 6: 1 = minor, 2 = moderate, 3 = serious, 4 = severe, 5 =
critical, and 6 = maximum (untreatable).
---------------------------------------------------------------------------

    UMTRI and IIHS argue that rear-facing CRSs are five times safer
than forward-facing CRSs, based on a 2007 study by Henary et al.\74\
NHTSA notes that the Henary study was called into question in 2016, and
after further analysis, the article was retracted by the journal Injury
Prevention, because the survey weights in the original analysis were
determined to be improperly handled. In 2017, a revised analysis of the
1988-2003 data, along with an extended analysis of the data through
2015, was published by a subset of the original authorship group.\75\
Their findings reveal that, although children 0 to 23 months still had
lower rates of injury while rear-facing compared with forward-facing,
the sample size was too small to achieve statistical significance.
---------------------------------------------------------------------------

    \74\ Supra.
    \75\ McMurry, T.L., Arbogast, K.B., Sherwood, C.P., Vaca, F.,
Bull, M., Crandall, J.R., Kent, R.W. ``Rear facing versus forward-
facing child restraints: an updated assessment,'' 2017, Injury
Prevention.
---------------------------------------------------------------------------

    Regardless of the withdrawn Henary study, NHTSA does not find the
commenters' arguments persuasive. MAP-21 limits our discretion
regarding rear-facing child restraints, but even in the absence of the
statutory mandate, NHTSA finds a crucial need to apply FMVSS No. 213a
to rear-facing CRSs. Current guidance from the American Academy of
Pediatrics (AAP) and from NHTSA instruct parents that children should
ride rear-facing longer, and increasing numbers of child restraints are
designed to position children rear-facing longer. AAP recommends: ``All
infants and toddlers should ride in a rear-facing seat until they reach
the highest weight or height allowed by their car safety seat
manufacturer. Most convertible seats have limits that will allow
children to ride rear facing for 2 years or more.'' \76\ NHTSA
recommends for children 1- to 3-years-old: ``Keep your child rear-
facing as long as possible. It's the best way to keep him or her safe.
Your child should remain in a rear-facing car seat until he or she
reaches the top height or weight limit allowed by your car seat's
manufacturer.'' \77\ Because of these recommendations and the advances
in child seat designs, children are positioned rear-facing longer.\78\
As most child occupant fatalities occur in front and side crashes,
NHTSA believes it is critical that child restraints meet not only the
Federal standard for frontal protection (FMVSS No. 213), but also a
Federal standard for side impact protection (FMVSS No. 213a). Issuing
FMVSS No. 213a guarantees the safety seats are tested and certified to
a robust side impact standard when used rear-facing, and that children
are provided at least a minimum level of protection against
unreasonable risk of death or injury in side crashes.
---------------------------------------------------------------------------

    \76\ https://www.healthychildren.org/English/safety-prevention/on-the-go/Pages/Car-Safety-Seats-Information-for-Families.aspx.
    \77\ https://www.nhtsa.gov/equipment/car-seats-and-booster-seats.
    \78\ Rear-facing car seat use among children 1- to 3-years-old
increased significantly from 9.4 percent in 2015 to 13.7 percent in
2017. Li, H.R., & Pickrell, T. (2018, September). The 2017 National
Survey of the Use of Booster Seats (Report No. DOT HS 812 617).
Washington, DC: National Highway Traffic Safety Administration.
---------------------------------------------------------------------------

b. Will child restraints become excessively large and heavy?

    Dr. Baer, UMTRI and IIHS raised concerns that child restraints
would get wider because of meeting FMVSS No. 213a. Dr. Baer commented
that the side impact rule is ``virtually ensuring that car seats are
only going to get wider and bulkier at the head area.'' The commenter
believed that the increased bulk would result in parents not able to
fit car seats side-by-side in rear seats, and so the oldest child will
be ``put into a backless booster, as this is typically the narrowest,
and least expensive, restraint available.'' UMTRI expressed concern
that adding larger, padded side structures ``has potential to increase
the overall width of child restraints,'' which could result in children
moved from center seating positions to outboard positions. IIHS echoed
this concern, and stated ``even moderate increases in size may result
in fewer seats that fit in the rear seats of smaller vehicles.''
    Conversely, ARCCA \79\ responded to the comments to the NPRM about
the potential increase in the size and weight of child restraints.
ARCCA shared information gained from car seats tested pursuant to a
side impact test found in European New Car Assessment Program (Euro-
NCAP) consumer education program. ARCCA stated that Euro-NCAP test
results are provided to the public to aid purchasers in the selection
of CRSs, and that as a result of these test programs, most suppliers of
European child seat manufacturers strive to score well in those tests.
---------------------------------------------------------------------------

    \79\ Comment dated July 1, 2014. There were two comments from
ARCCA.
---------------------------------------------------------------------------

    ARCCA believed that FMVSS No. 213a will have minimal effect on CRS
cost, weight, and width. The commenter supported its view with an
example of an infant-only CRS sold in Europe and the U.S. The
restraint's European version differs from the U.S. version by way of
side wings with a wing depth of 4\1/2\ inches, compared to the U.S.
version that has a wing depth of only 2\1/2\ inches. ARCCA stated that
when tested with a 12-month-old CRABI infant dummy in accordance with
the proposed ISO side impact test protocol,\80\ the U.S. version failed
to contain the head. The head hit the simulated intruding door,
resulting in HIC values ranging from 2,577 to 4,783. In contrast, the
commenter stated, the European version, with its deeper side wings,
contained the head and prevented contact with the simulated intruding
door, resulting in a HIC value of 827 (a 68 to 83 percent reduction in
the HIC value).
---------------------------------------------------------------------------

    \80\ ARCCA did not provide details of the ISO test protocol.
ARCCA may be referring to the test details provided in the report,
ISO TR 14646:2007, ``Road vehicles--Side impact testing of child
restraint systems--Review of background data and test methods, and
conclusions from the ISO work as of November 2005.''

---------------------------------------------------------------------------

    ARCCA stated that the U.S. and European versions of this infant
seat were manufactured using the same plastic shell. The side wings of
the European version were deepened simply by extending the expanded
polystyrene (EPS) lining beyond the plastic shell. While the wings were
deepened in the European version, the width of the infant seat was the
same as the U.S. version. ARCCA stated that the weight increase due to
the deepening of side wings was negligible (approximately one-eighth of
a pound (\1/8\ lb)) and the increased cost for the extended EPS was
minimal, less than one dollar. ARCCA believed the proposed rulemaking
will significantly improve child occupant crash protection in side
impacts and rollovers, and have minimal effect on CSS cost, weight, and
width.
Agency Response
    Data indicate that child restraints will not become excessively
large or heavy due to FMVSS No. 213a, and rear-facing CRSs should not
be excluded from the side impact protection requirements based on a
concern about larger and wider CRS designs. As IIHS points out, only
one rear-facing seat failed to contain the 12-month-old CRABI's head in
NHTSA's test program described in the NPRM, which indicates that many
rear-facing seats may not need to be redesigned in any way to meet
FMVSS No. 213a.
    Commenters Dr. Baer, UMTRI and IIHS speculated about bulkier child
restraints and the consequences that the bulkiness could cause, but
provided no data or other information supporting their views. In
contrast, ARCCA provided information showing that the width and weight
of an infant carrier sold in Europe (designed to provide side impact
protection) were almost identical to the U.S. version of the model.
ARCCA's information indicates side impact protection can be provided by
car seats without having to increase width or weight.
    After reviewing the comments, NHTSA followed up with further
evaluation of whether manufacturers must widen forward-facing
restraints to meet the side impact protection requirements. The agency
evaluated two pairs of CRS models.\81\ For each pair, one of the child
restraints was advertised as providing more side impact protection than
its related twin. NHTSA measured the width of each CRS at the locations
where a child's head, abdomen and hips would be when restrained in the
CRS. NHTSA found that, for each CRS advertised as having enhanced side
impact protection features over its twin, each was wider in the upper
area of the CRS near the head position.
---------------------------------------------------------------------------

    \81\ Louden, A., & Wietholter, K. (2022, March). FMVSS No. 213
side impact test evaluation and revision (Report No. DOT HS 812
791). Washington, DC: National Highway Traffic Safety Administration
(hereinafter Louden & Wietholter (2022)). Available in the docket of
this final rule.
---------------------------------------------------------------------------

    NHTSA then conducted sled tests of the CRSs using the Q3s dummy
with the CRS in the forward-facing mode. For each CRS pair, the agency
observed that the HIC15 value measured by the Q3s dummy was greater for
the wider CRS (see Table 10). The HIC15 measurements of the Q3s were
greater for both the Britax Advocate and Graco Nautilus Safety
Surround, which are wider than their corresponding models, the Britax
Boulevard and Graco Nautilus 65, respectively. This testing
demonstrated that child restraints cannot simply be widened to meet the
FMVSS No. 213a side impact test; simply widening the restraint may, in
fact, degrade performance. Manufacturers will likely use different
engineering solutions (e.g., designing in energy-absorbing components)
to improve performance rather than just widen the restraint. A well-
engineered restraint could meet the requirements of this final rule
without becoming wider.
    Concerns about rear-facing CRSs ``bulking-up'' to meet the side
impact protection requirements also appear unwarranted. As will be
discussed in a section below, test data from NHTSA's tests developing
this final rule indicate that not all side wings and padding protect
the same, and in some cases, ``more'' of a countermeasure (padding,
structure) was not necessarily ``better.'' Width, wings, padding,
padding-like features, and other countermeasures employed to provide
protection in side impacts must be engineered to attain the performance
specified by FMVSS No. 213a. Adding bulk and weight to a child
restraint is not necessary and can be counterproductive.

 Table 10--Upper Width and HIC15 Values in Tests With the Q3s Dummy in Britax Boulevard and Britax Advocate CRS
                                     Models in Forward-Facing Configuration
----------------------------------------------------------------------------------------------------------------
                                                                             Advertised side
        Database  test No.                 CRS               HIC15             protection           Upper width
----------------------------------------------------------------------------------------------------------------
CRS Pair 1:
    10105........................  Britax Boulevard...             522  2 Layers of Side Impact              460
                                                                         Protection (energy-
                                                                         absorbing shell and
                                                                         foam-lined head rest).
    10106........................  Britax Advocate....             665  3 Layers of Side Impact              465
                                                                         Protection (energy
                                                                         absorbing shell, foam-
                                                                         lined headrest and
                                                                         external cushions).
CRS Pair 2:
    10108........................  Graco Nautilus 65..             609  EPS Energy Absorbing                 455
                                                                         Foam and Reinforced
                                                                         Steel.
    10109........................  Graco Nautilus                  838  EPS Energy Absorbing                 470
                                    Safety Surround.                     Foam, Reinforced Steel
                                                                         and Safety Surround
                                                                         Technology (safety
                                                                         surround means that the
                                                                         head rest has a thicker
                                                                         foam).
----------------------------------------------------------------------------------------------------------------

    NHTSA also believes there is a technical incentive in FMVSS No.
213a that encourages designs toward narrower CRSs. Under this final
rule, the impact velocity between the door and the CRS will be lower
for narrow CRSs compared to wider CRSs. Narrower CRSs are at a greater
distance from the edge of the sliding seat and so the door will impact
the CRS at a later time after first impacting the sliding seat. This
later impact will result in a lower relative velocity of the sliding
seat with respect to the door at the time of impact with the CRS.
    NHTSA studied this aspect of the test procedure in following up on
the commenters' concern about the widths of CRSs. NHTSA analyzed the
relative velocity at impact time between the door and the CRS for a
wide CRS (Safety 1st Advanced Air+, 520 mm maximum width) and narrow
CRS (Chicco Next Fit, 460 mm maximum width). As shown in Figure 1
below, the wider CRS is impacted by the door at a relative velocity of
29.19 km/h while the narrow one is impacted at 26.59 km/h. Both HIC15
and chest deflection were lower in the test of the narrow CRS (Chicco

Next Fit) than the wide CRS (Safety 1st Advance SE Air+). These CRSs
are designed differently, so their countermeasures could have affected
the HIC15 and chest deflection values measured by the dummy in the
tests. Yet these results suggest that the FMVSS No. 213 side impact
test will not in and of itself lead to wider CRSs.
    In sum, based on NHTSA's testing of various types of CRSs in the
side impact test protocol, NHTSA believes that CRSs do not have to be
wider or bulkier to meet the side impact performance requirements. In
fact, our evaluations showed that some narrower CRSs performed better
than wider CRSs.
[GRAPHIC] [TIFF OMITTED] TR30JN22.004

c. More Bulk Is Not Necessarily Advantageous; the 2017 Test Program

    In 2017, NHTSA tested child restraint systems on the side impact
seat assembly (SISA) as configured to the specifications of this final
rule. There were two parts to this program. The first part of the
testing was conducted to compare results of tests on the final SISA
configuration with test results from 2012 using the proposed SISA.