[Federal Register Volume 73, Number 134 (Friday, July 11, 2008)]
[Notices]
[Pages 40016-40050]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-15620]
[[Page 40015]]
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Part II
Department of Transportation
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National Highway Traffic Safety Administration
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Consumer Information; New Car Assessment Program; Notice
Federal Register / Vol. 73, No. 134 / Friday, July 11, 2008 /
Notices
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DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration
[Docket No. NHTSA-2006-26555]
Consumer Information; New Car Assessment Program
AGENCY: National Highway Traffic Safety Administration (NHTSA),
Department of Transportation (DOT).
ACTION: Final decision notice.
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SUMMARY: On January 25, 2007, NHTSA published a notice announcing a
public hearing and requesting comments on an agency report titled,
``The New Car Assessment Program (NCAP) Suggested Approaches for Future
Program Enhancements.'' This notice summarizes the comments received
and provides the agency's decision on how it will improve the NCAP
ratings program.
For model year (MY) 2010, the agency will make changes to its
existing front and side crash rating programs. For the frontal crash
test program, NHTSA will maintain the 35 mph (56 kmph) full frontal
barrier test protocol but will update the test dummies and associated
injury criteria used to assess and assign a vehicle's frontal impact
star rating. For side impact, NHTSA will maintain the current moving
deformable barrier test at 38.5 mph (63 kmph) but will update that test
to include new side impact test dummies and new injury criteria that
are used to assign a vehicle's side impact star rating. Additionally,
vehicles will also be assessed using a new pole test and a small female
crash test dummy.
For rollover, the agency will continue to rate vehicles for
rollover propensity, but will wait to update its rollover risk model to
allow for more real-world crash data of vehicles equipped with
electronic stability control.
Also for MY 2010, the agency will implement a new ratings program
that will rate vehicles on the presence of select advanced technologies
and establish a new overall Vehicle Safety Score that will combine the
star ratings from the front, side, and rollover programs.
Finally, for the agency's vehicle labeling program, we are
announcing that the side score, rather than being based only on the
moving deformable barrier test, will be based on the combination of the
moving deformable barrier test and the pole test. Additionally, the
agency will initiate rulemaking to include the new overall
crashworthiness rating on the Monroney label.
DATES: These changes to the New Car Assessment Program are effective
for the 2010 model year.
FOR FURTHER INFORMATION CONTACT: For technical issues concerning the
enhancements to NCAP, contact Mr. Nathaniel Beuse or Mr. John Hinch.
Telephone: (202) 366-9700. Facsimile: (202) 493-2739. For legal issues,
contact Dorothy Nakama, NHTSA Office of Chief Counsel, Telephone (202)
366-2992. Facsimile: (202) 366-3820. You may send mail to these
officials at: The National Highway Traffic Safety Administration,
Attention: NVS-010, 1200 New Jersey Avenue, SE., Washington, DC 20590.
SUPPLEMENTARY INFORMATION:
I. Introduction
II. Summary of Request for Comments
A. Frontal NCAP
B. Side NCAP
C. Rollover NCAP
D. Rear Impact
E. Crash Avoidance Technologies
F. Presentation and Dissemination of NCAP information
G. Manufacturer Self-Certification
III. Summary of Comments
A. Frontal NCAP
1. Impact Protocol
2. Test Dummies (in the Front Seating Position)
3. Injury Criteria
4. Test Speed
B. Side NCAP
1. Oblique Pole Test (Test Dummies and Implementation Time)
2. Moving Barrier Protocol (Test Speed, Test Dummies, and Injury
Criteria)
C. Rollover NCAP
1. Rollover Risk Model
2. Dynamic Rollover Structural Test
D. Rear Impact
1. Basic Information
2. Links to the IIHS
3. Dynamic Test
E. Crash Avoidance Technologies
1. Program Implementation
2. Selected Technologies
3. Rating System
F. Presentation of NCAP Information
Combined Crashworthiness Rating
G. Manufacturer Self-Certification (of NCAP Results)
H. Other Suggestions
IV. Discussion and Agency Decision
A. Frontal NCAP
B. Side NCAP
C. Rollover NCAP
D. Rear Impact
E. Crash Avoidance Technologies
F. Presentation and Dissemination of Safety Information
G. Manufacturer Self-Certification
H. Other Recommendations
I. Monroney Label
V. Conclusion
Appendix A
Appendix B
Appendix C
Appendix D
I. Introduction
The National Highway Traffic Safety Administration (NHTSA) is
responsible for reducing deaths, injuries, and economic losses
resulting from motor vehicle crashes. One way in which NHTSA
accomplishes this mission is by providing consumer information to the
public. NHTSA established the New Car Assessment Program (NCAP) in 1978
in response to Title II of the Motor Vehicle Information and Cost
Savings Act of 1972. Through NCAP, NHTSA currently conducts tests and
provides frontal and side crash, and rollover ratings and communicates
the results using a five-star rating system. With this information,
consumers can make better-informed decisions about their purchases. In
turn, manufacturers respond to the ratings by voluntarily improving the
safety of their vehicles beyond the minimum Federal safety standards.
For MY 1979, when the agency began rating vehicles for frontal
impact safety, fewer than 30 percent of vehicles tested would have
received the top ratings of 4 or 5 stars for the driver seating
position.\1\ By comparison, for MY 2007, 98 percent of vehicles
received 4 and 5 stars in the frontal NCAP rating for that same seating
position. Equally impressive is that while it took almost 30 years to
reach this level for frontal NCAP performance, the more recent NCAP
programs, like side and rollover NCAP, have started reaching this level
of safety performance at a pace that can be measured in years rather
than decades. The agency believes that consumers continue to consider
safety in their purchasing decisions and are demanding ever-increasing
levels of safety.
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\1\ NHTSA began using stars in model year 1994. See 69 FR 61072,
Docket No. NHTSA-2004-18765.
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Similarly, recent advances in crash avoidance technology offer a
new opportunity for NCAP to further enhance its ability to inform
consumers about new systems and encourage them to purchase systems that
NHTSA has found to be effective in improving safety.
On January 25, 2007 NHTSA published a notice outlining proposed
enhancements to the NCAP activities. In this notice, we requested
comments on any additional actions that the agency could undertake so
that the program could continue to provide consumers with relevant
safety information.\2\ These enhancements included new test dummies and
injury criteria for frontal NCAP, the addition of a new side pole test,
new test dummies, and new injury
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criteria for side NCAP, an overall summary rating, and a new program to
promote advanced crash avoidance technologies. Additionally, the notice
announced a March 7, 2007 public hearing to allow interested parties
the opportunity to address the suggested approaches for enhancing the
program.
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\2\ 72 FR 3473, Docket No. NHTSA-2006-26555.
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Seventy-six (76) individual comments were received in response to
the notice and the public hearing.\3\ Commenters offered mixed
responses to the various proposals for enhancing NCAP; however, most
commenters commended the agency's initiative to reexamine the program
and supported the proposed approaches. This notice summarizes comments
to the January 2007 notice, the March 2007 public hearing, and provides
the agency's decision on how it will proceed with changes to NCAP.
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\3\ This count does not include duplicative or multiple comments
from the same source.
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I. Summary of Request for Comments
In its notice, the agency presented proposals to improve not only
the program's current front, side and rollover activities, but also
approaches to improve its information with regards to rear impact, and
certain crash avoidance (or active safety) technologies such as
Electronic Stability Control (ESC). NHTSA also outlined alternatives to
enhance the presentation and dissemination of safety information to
consumers, and solicited feedback for additional considerations that
would allow NCAP to remain effective and relevant in improving vehicle
safety.
A. Frontal NCAP
NHTSA proposed three approaches to enhance the frontal NCAP. The
first approach was to maintain the current 35 mph (56 kmph) test
protocol with a 50th percentile male Hybrid III dummy, but to account
for injuries to the knee/thigh/hip (KTH) complex. This would be
accomplished by including a new injury criterion into the formula used
to calculate the frontal NCAP rating for the driver and front passenger
seating positions. Second, while keeping the test protocol the same,
the agency considered determining whether injury measures obtained
below the knee using the Denton or Thor-Lx dummy legs are predictive of
real-world injuries. Last, the agency considered evaluating vehicles
based on a lower test speed.
B. Side NCAP
To enhance its side impact safety ratings, the agency presented two
approaches for consideration. NHTSA proposed continuing to rate
vehicles using the moving deformable barrier test protocol but would
also encourage manufacturers to provide better head and pelvis
protection by including the side impact pole test and the new test
dummies recently finalized in Federal Motor Vehicle Safety Standard
(FMVSS) No. 214 ``Side Impact Protection'' prior to the performance
requirements being fully phased-in.\4\ Furthermore, the agency proposed
research that would focus on the assessment of the injury mechanisms in
a fully equipped side impact air bag fleet. The purpose of the research
would be to evaluate how serious injuries occur in the new fleet and to
develop test procedures to reflect these impact conditions. The outcome
of this research could lead to a new barrier test protocol (which could
include increased test speed and different barrier characteristics).
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\4\ 73 FR 32473, Docket No. NHTSA-2008-0104. On June 9, 2008 the
agency responded to petitions for reconsideration of the final rule,
changing the effective date of the pole test. Now, with certain
exceptions, all vehicles have to meet the upgraded pole test by
September 1, 2014.
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C. Rollover NCAP
To enhance its rollover program, the agency indicated that it would
continue tracking the rollover rate and the single vehicle crash rate
of vehicles equipped with ESC to create a new rollover risk model.
D. Rear Impact
Currently, NHTSA does not provide consumer information on rear
impacts. However, NHTSA is aware of recent research suggesting that
consumers are concerned about rear crashes. As such, the agency
proposed two approaches. First, NHTSA proposed that it could provide
consumers with basic information on rear crashes such as safe driving
behavior, proper adjustment of head restraints, real-world safety data
by vehicle classes, and links to the Insurance Institute of Highway
Safety (IIHS) rear impact test results. Second, as a longer term
approach, the agency proposed that a dynamic test, which addresses
those injuries not covered by the agency's current standards, could be
investigated and incorporated into the ratings program.
E. Crash Avoidance Technologies
Technologies such as ESC, forward collision warning (FCW), lane
departure warning (LDW) and crash mitigation systems have been
developed and are being offered in the current vehicle fleet. Some of
these technologies have shown effectiveness in reducing the number of
relevant crashes in Department of Transportation (DOT)-sponsored field
operational tests.\5\ Research by the agency and others has shown that
consumers are generally unaware of these technologies or their
potential safety benefits. As a result, the agency believed that NCAP
should be used to better highlight those beneficial technologies to
consumers and sought to establish a new ratings program that evaluated
vehicles on the presence of proven crash avoidance technologies. Based
on technical maturity, fleet availability, and available effectiveness
data, NHTSA identified three technologies that fit these criteria.
These technologies are ESC, LDW, and FCW.
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\5\ See 72 FR 3475, Docket No. NHTSA-2006-26555.
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NHTSA proposed two possible approaches and illustrated a possible
implementation of the program with an A, B, C letter grade system.
First, the agency proposed that each of the technologies would have
equal weight. For example, if a vehicle had only one technology, it
would receive a C; whereas, another vehicle that had all three
technologies would receive an A. Approach two would attempt to quantify
a technology's real-world benefits by taking into account the target
population and anticipated effectiveness of the technology to decide
whether a particular type of technology would be given more weighting
than another and thus prompt a higher score. For example, in this
scheme, if ESC was found to be more effective than lane departure, a
vehicle equipped only with ESC could receive a B versus a vehicle
equipped only with lane departure warning which would receive a C
rating.
It was further stated that this second approach could be expanded
into a more comprehensive performance-based crash avoidance rating. As
the technologies evolved and as the agency gathered more information
related to various versions of these technologies and their associated
safety effectiveness, NHTSA proposed that a safety score (i.e., star
rating) on individual technologies could then be developed (e.g.,
different version of ESC might yield different performance results and
thus a different star rating).
F. Presentation and Dissemination of NCAP Information
Combined Crashworthiness Rating
Several NHTSA-sponsored research reports and consumer surveys, as
well as a Government Accountability Office and a National Academy of
Sciences review of NCAP, have all pointed to the public's desire for a
summary safety rating. Similarly, other consumer information programs
around the world
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such as the IIHS, Japan NCAP, and EuroNCAP use summary ratings that
combine their respective crashworthiness tests. The agency proposed two
summary crashworthiness rating concepts. In both concepts, the existing
rollover rating was not included in the calculation of the overall
summary rating, and star rating boundaries would have to be developed
for both individual crash tests and the overall summary rating.
The first approach computed the overall crashworthiness rating by
first averaging the driver and right front passenger dummy injury
results from the frontal crash mode into a single star rating. The same
would be done for the seating positions in the side crash mode to
compute the overall side crash rating. To compute the overall
crashworthiness rating, the overall frontal and the overall side impact
performance would be combined by using weighting factors obtained from
real-world data (i.e. the National Automotive Sampling System (NASS)).
Each individual total (overall front and overall side) would be
weighted by that crash mode's contribution to the total injuries
occurring in the real-world.
The second approach computed the overall crashworthiness rating by
normalizing the seating positions for each individual crash mode (front
and side) using the Injury Assessment Reference Values (IARVs)
established for that dummy, body region, and crash mode. Using the NASS
data, these normalized values would then be multiplied by the
occurrence of that injury in the real-world. Body injury regions that
are coded by NASS but are not measured by the dummy and/or not selected
by NHTSA for inclusion in the rating would be equally distributed among
the remaining body regions.
Presentation of Safety Information
As the consumer's use of the Internet for vehicle safety
information has grown, so has the need to consolidate and better
present NCAP vehicle safety information to consumers on http://www.safercar.gov. The four approaches proposed by the agency were: (1)
Developing other topical areas under the Equipment and Safety section
of the Web site; (2) redesigning the Web site to improve organization;
(3) improving search capabilities on the Web site; and, (4) combining
agency recall and ratings database information.
G. Manufacturer Self-Certification
In addition to NHTSA's proposed suggestions in the notice the
agency also sought comment at the public hearing on whether or not
manufacturers should be allowed to conduct and publish their own NCAP
ratings via a self-certification process. We indicated that such an
approach would be one way to improve not only the timeliness of NCAP
ratings but also to increase the number of vehicles rated by the
agency.
III. Summary of Comments
This section provides a brief summary of the seventy-six (76)
comments submitted to the docket by vehicle manufacturers, safety
advocates, public health groups and the general public in response to
the notice and the public hearing.\6\ It should be noted that comments
unique to the public hearing are stated as such.
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\6\ These submissions are available at http://www.regulations.gov in Docket No. NHTSA-2006-26555.
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A. Frontal NCAP
Comments regarding NHTSA's frontal program are grouped into four
categories: Impact Protocol, Test Dummies (in the Front Seating
Position), Injury Criteria and Test Speed.
1. Impact Protocol
The Alliance of Automobile Manufacturers (Alliance), Automotive
Occupant Restraints Council (AORC), Toyota Motor North America, Inc.
(Toyota), BMW of North America (BMW), Fuji Heavy Industries USA, Inc.
(Subaru) and Volkswagen of America, Inc. (VW) supported the retention
of the current frontal crash test protocol at 35 mph (56 kmph).
Consumers Union and Public Citizen suggested adding an offset frontal
crash test rating, which Public Citizen believed would be far more
useful in assessing the structural integrity of different vehicle
models. Likewise, Toyota also encouraged NHTSA to investigate ways to
include information on offset collision conditions in its NCAP program.
Toyota explained that their investigation of National Automotive
Sampling System Crashworthiness Data System (NASS-CDS) data showed that
an overwhelming majority of frontal crashes occur in either the full
overlap or offset condition. They believed that vehicle performance
assessed in the offset condition should yield relevant improvements in
safety technology and provide considerable benefit.
IIHS and Subaru recommended the addition of a frontal pole test to
address significant injuries resulting from impacts with narrow
objects. IIHS asserted that offset tests more closely simulate impacts
with narrow objects than do full-width tests, and that a narrow-object
NCAP test could have an important impact on real-world vehicle
crashworthiness, and would give consumers a wide range of results to
inform their purchasing decisions. Subaru suggested that NHTSA should
study and possibly propose a frontal pole test for inclusion into NCAP
if the frequency of frontal crashes with narrow objects is high.
However, General Motors North America (GM) asserted that a pole test is
unlikely to result in significant change or further improvement in
structural stability and resultant injury reduction. They stated that
research in this area may yield only limited or incremental gains in
injury mitigation, and that the public interest is likely to be better
served by channeling resources into areas that could produce greater
societal benefit.
2. Test Dummies (in the Front Seating Position)
With regard to test dummies, the Alliance stated that test dummies
in frontal NCAP should be the same as those in FMVSS No. 208.
Additionally, GM, AORC, Consumers Union and the Alliance supported the
use of the 5th percentile female Hybrid III dummy in the right front
passenger position. GM provided NASS data which suggested that small
females were over-represented (with regard to serious injuries) in the
right front passenger seating position. GM also suggested that in the
future, the 5th percentile female dummy should be used in both seating
positions to optimize safety. AORC asserted that the substitution of
the 5th female for the 50th percentile male would demonstrate a broader
population range of protection since some data has been shown which
suggests that the weighted frequency of serious and fatal injuries to
women is greater than to men in the right front passenger seating
position.
Furthermore, Consumers Union asserted that the agency should
investigate using the 5th percentile female and 95th percentile male
dummies to evaluate NCAP tests for all sizes of vehicle occupants.
Subaru supported the continued use of 50th percentile adult male
dummies in both front seating positions indicating that this was more
representative of real-world occupants. Subaru also asserted that
additional tests with other dummies, such as the 5th percentile adult
female, should be done only if well supported by real-world data.
3. Injury Criteria
Most vehicle manufacturers agreed that NHTSA should develop and
incorporate a KTH injury criterion into
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the NCAP frontal rating. They noted that a KTH assessment would drive
vehicle countermeasures that could mitigate lower leg injuries and also
yield important information relevant to vehicle design. Likewise,
adding KTH and/or lower leg injury criteria to the NCAP rating protocol
could expand the usefulness of the NCAP system by addressing the
societal cost of Abbreviated Injury Scale (AIS) 2+ injuries. The
Alliance, Autoliv, Consumers Union and IIHS also supported NHTSA's
efforts to incorporate a KTH injury criterion into the frontal program.
However, IIHS urged the agency to concentrate its research tests on
serious injuries and fatalities in frontal impacts to encourage more
protective vehicle design. Additionally, Autoliv stated that although a
reduction in KTH injuries would have a significant impact on societal
cost, they believed that it would have little effect in reducing
fatalities.
Nissan North America (Nissan) stated that the agency should
consider a KTH assessment only after further study is conducted.
Instead, Nissan urged NHTSA to harmonize knee and thigh injury values
with those required in Japanese and European regulations. Likewise, the
Association of International Automobile Manufacturers (AIAM) did not
believe that the agency should move expeditiously to include a KTH
criterion in the current frontal NCAP program since the agency had
identified crashes of lower test speed as the primary concern regarding
leg injuries. They recommended that NHTSA present the analysis and
results of their KTH research for public comment prior to including a
KTH criterion in the frontal program.
For lower leg assessments, several commenters suggested that
additional research was needed to determine whether injury measures
obtained below the knee were predictive of real-world injury. GM noted
that adding a femur load injury criterion to frontal NCAP would drive
many of the same vehicle countermeasures that would mitigate lower leg
injuries.
With regards to what anthropomorphic test device (ATD) could be
used for these new criteria (KTH and lower leg), Honda specifically
stated that a KTH assessment would be possible using the Denton dummy
leg. For injuries to the lower leg (below the knee), Honda, Subaru,
Nissan, and Volvo Cars of North America, LLC (Volvo), suggested that
the agency adopt the Thor-Lx legs in the future. The Alliance did not
support the introduction of either the Denton or Thor-Lx legs unless
they were included in FMVSS No. 208. Furthermore, VW believed that
these test devices must be validated, and the applicable injury
criteria and rating must be verified for correlation with real-world
safety.
Some commenters suggested that all injury criteria incorporated in
FMVSS No. 208 (beyond head injury criteria and chest acceleration
criteria) should also be included in frontal NCAP. Specifically, Honda,
Ford, GM, the Alliance, and Autoliv supported the inclusion of a chest
deflection criterion into the frontal NCAP rating based on NASS-CDS
data indicating a substantial number of injuries to ribs and internal
organs resulting in AIS 3+ or higher severity injuries. However, Honda
stated that the current chest deflection calibration procedure may not
be appropriate to assure that chest deflection measurements are
accurate enough to provide useful data. GM and the Alliance recommended
including a chest compression criterion into frontal NCAP. The Alliance
urged NHTSA to conduct research on neck (tension) injury criteria
before including it into frontal NCAP. However, GM suggested that the
agency add neck injury criteria to frontal NCAP since these criteria
are already measured by the Hybrid III dummies and included in FMVSS
No. 208.
4. Test Speed
With regards to adopting a lower test speed, the Alliance, GM and
Volvo agreed with NHTSA's analysis and supported the agency's proposal
to conduct more research on lower test speeds. However, VW questioned
whether lower speed crashes represented a greater risk of occupant
injury than the current NCAP test procedure. Therefore, VW as well as
the Alliance believed that an additional test in frontal NCAP would add
significant expense and strain on available resources without any
commensurate advantages or benefit.
Subaru asserted that they did not support adding low speed bumper
tests to frontal NCAP since those tests would overlap with existing
IIHS tests.
Two individual commenters, Mr. Dainius Dalmotas and Dr. Harold
Mertz stated that a full vehicle crash test designed to promote
enhanced chest protection in low-to-moderate speed frontal crashes
would be most promising since the vast majority of serious and fatal
injuries among belted drivers occur at collision speeds of 25 mph (40
kmph) or less. They also asserted that incentives to promote improved
safety in low-to-moderate speed frontal impacts were lacking and could
be addressed through NCAP.
At the public hearing, Consumers Federation of America (CFA) and
the Center for Auto Safety (CAS) suggested that NHTSA increase test
speeds and challenge manufacturers to post the highest speed at which
their vehicles are tested, in order to differentiate amongst the
performance of vehicles. However, the Alliance, Consumers Union, AIAM
and Subaru opposed a higher speed test for frontal NCAP. The Alliance
stated that field data did not show the need for higher test speeds.
AIAM and Consumers Union did not believe that increasing crash test
speeds would benefit the overall safety of occupants; but rather, it
could cause vehicles to become stiffer. Subaru asserted that a higher
speed test is not representative of the vast majority of fatal crashes,
does not enhance NCAP's consumer information goals, and risks
increasing vehicle aggressiveness.
B. Side NCAP
Comments regarding NHTSA's side program are divided into the
following categories: Oblique Pole Test (Test Dummies and
Implementation Time), Moving Barrier Protocol (Test Speed, Test
Dummies, and Injury Criteria), and Side NCAP Research.
1. Oblique Pole Test (Test Dummies and Implementation Time)
GM, Subaru, Toyota, the Alliance, and Autoliv agreed with the
agency's proposal to incorporate an oblique pole test into NCAP.
However, with regards to adopting the oblique pole test prior to the
completion of the FMVSS No. 214 pole test phase-in, BMW, Ford, Toyota,
and the Alliance, asserted that such action would be premature, and
these commenters suggested that NHTSA adopt the test after the oblique
pole test had been fully phased-in. Furthermore, Subaru suggested that
3 years be allowed after the agency announced a new test before rating
vehicles under the new test protocol.
Toyota explained that they understood NHTSA's intention to use an
early introduction of the pole test to drive the installation of
advanced head protection systems (like curtain airbags), but they
believed that significant benefits in head protection were already
being realized from the introduction of curtain air bags, which was
driven by industry's commitment to the industry voluntary compatibility
requirements.\7\
[[Page 40020]]
Therefore, Toyota recommended additional investigation into whether
there are merits of an early introduction of an oblique pole test into
NCAP. Honda recommended adding to the existing side impact test by
introducing a second side impact test that is similar to the current
IIHS moving deformable barrier (MDB) test.\8\ Honda suggested that this
would extend the coverage of NHTSA's side impact testing, be more
representative of real-world crashes, and help to provide a more
realistic assessment of a vehicle's crashworthiness in these types of
two-vehicle collisions.
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\7\ IIHS and the Alliance created a voluntary agreement wherein
automotive manufacturers agreed to improve occupant protection in
front and side crashes involving cars and light trucks. For front-
to-side impacts, most automakers agreed to design their vehicles to
meet the head injury performance requirements of NHTSA's FMVSS No.
201 side-pole test or the IIHS moving deformable barrier test. By
September 1, 2007, at least half of all new passenger vehicles would
meet one of the two requirements, and by September 1, 2009 model
year, all new passenger vehicles would meet the head injury
requirements of the Institute's moving deformable barrier test.
\8\ This test would represent an SUV to subject vehicle crash
(IIHS Side Impact Crash Evaluation test procedure--SICE).
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If the agency went forward with an oblique pole test, Subaru
recommended a side impact assessment based on two tests (the oblique
pole test and IIHS's MDB test) with head injury criteria and the SID-
IIs dummy, as long as the results could be combined into a single
rating. BMW and the Alliance suggested that the 5th percentile female
SID-IIs dummy be used for the driver position in the oblique pole test.
BMW asserted that the smaller SID-IIs dummy is most appropriate for
determining the geometric coverage area required for a curtain airbag.
The Alliance believed that it is appropriate to test only with the 5th
percentile female dummy in the front seating position because this is a
very severe test condition, and it would serve to meet the intent of
NCAP while minimizing additional test burdens on NHTSA and the
automotive industry.
Honda, Nissan and VW did not support the inclusion of an oblique
pole test into side NCAP. Honda believed that introducing an oblique
pole test would be a temporary measure until the test was fully phased-
in as a requirement for FMVSS No. 214. To comply with the requirements
of FMVSS No. 214, the head protection benefits of the oblique pole test
would already have been realized in every vehicle, so there would be
little practical benefit to consumers as a result of temporarily
including such a test in NCAP. VW and Nissan, similar to Toyota, stated
that automobile manufacturers were already committed to front-to-side
impact protection, and that the addition of a side impact pole test
would provide no added incentive for the manufacturers to implement
additional side impact protection. Nissan also believed that
incorporating the pole test into NCAP is unnecessary to encourage head
protection in new vehicles.
IIHS stated that the current NCAP barrier test did not fully
address the mix of vehicles on the road and that the agency needed to
improve the existing side impact barrier. IIHS suggested giving greater
priority to adopting or modifying the IIHS side impact barrier rather
than incorporating a new oblique pole test. However, GM asserted that
the pole test is structurally more challenging than the IIHS MDB test,
and that the IIHS MDB test and the pole test will not necessarily drive
installation of the same air bag solutions.
2. Moving Barrier Protocol (Test Speed, Test Dummies, and Injury
Criteria)
NHTSA proposed a new side NCAP barrier test protocol that would
include new dummies and additional injury criteria. The Alliance
supported the maintenance of the current barrier test but they
suggested a revised, lower test speed of 33.5 mph (54 kmph).
With regards to the incorporation of new dummies into the side MDB
test, the Alliance, Subaru, Honda, Nissan, Volvo, and AIAM proposed the
incorporation of WorldSID into NCAP. Specifically, Volvo and the
Alliance suggested that the WorldSID dummy should be introduced in
FMVSS No. 214 and NCAP simultaneously. Honda stated that the WorldSID
dummy provides excellent biofidelity, and does not present problems
with rib guide shape that the ES-2re dummy appears to have based on
their evaluation. AORC believed that the current test dummy does not
adequately address head injuries, and they encouraged NHTSA to use
either EuroSID-2 and/or the SID-IIs side impact dummy.
Volvo recommended that the dummies and injury criteria for the NCAP
side barrier test procedures be the same as they are for FMVSS No. 214.
Volvo supported the addition of head injury criteria in the NCAP
evaluation for the side barrier; however, they would prefer that the
NCAP criteria limits are set more stringent in order to encourage
manufacturers to exceed the performance standards outlined in the legal
requirement. BMW recommended that NHTSA use the ES-2re dummy for the
driver position in the MDB test because the SID-IIs dummy is already
included in the MDB test conducted by IIHS, and the biofidelity of the
SID-IIs dummy in these types of impacts is well understood. GM also
suggested the ES-2re dummy for the driver position since the most
frequent occupant, and most frequently injured occupant type at the
driver position is an adult male.
Autoliv asserted that the ES-2re dummy should be used for the front
seating position in both the oblique pole and MDB tests, as this dummy
represents the largest percentage of front seat occupants. They also
recommended the SID-IIs dummy for the rear seating position to provide
information on protection for older children and small adults seated in
the rear. GM also recommended the SID-IIs dummy for the rear seating
position because more frail persons tend to sit in the rear, the SID-
IIs dummy is tuned for frail occupants, and placement in the rear will
import safety improvements across the range of occupants.
3. Side NCAP Research
As a longer term approach, the agency suggested research into the
moving barrier test protocol to address injuries and fatalities that
might occur in vehicles equipped with curtain and side impact air bags.
The agency indicated this research could lead to a new barrier, an
increased barrier test speed, and a reevaluation of the impact
configuration.
The Alliance, AIAM, Honda and Subaru agreed that NHTSA should
analyze real-world side impact crashes for vehicles with side curtain
airbags. However, the Alliance recommended that the agency and
automotive industry should develop more experience with the new pole
test and test dummies before considering any increase in test speeds.
In addition, the Alliance asserted that future research should evaluate
whether it would be beneficial for NCAP to harmonize with the existing
IIHS barrier.
Toyota supported additional research efforts to gain a better
understanding of the potential for and the necessity of changes to the
test device and configuration for vehicles equipped with side airbags.
Furthermore, Toyota stated that questions remain relating to barrier
characteristics, injury criteria and appropriate ATDs that should be
researched from relevant field data.\9\
---------------------------------------------------------------------------
\9\ In particular, Toyota recommended continued investigation
into previously identified concerns with the performance of the SID-
IIs upper arm, which they believed was not biofidelic and affected
the thoracic rib response.
---------------------------------------------------------------------------
Autoliv recommended that NHTSA research increasing the test speed
and develop a single test that would assess both the head and thorax
injury protection systems installed in newer vehicles. Autoliv also
suggested that the adoption of the WorldSID dummy would be suitable if
incorporated into Part 572 and FMVSS No. 214.
[[Page 40021]]
Additionally, Delphi opposed releasing a new regulation under FMVSS No.
214 and then promoting a different set of barrier protocols, dummy
types and injury metrics for side NCAP evaluation since that decision
could cause misdirection for original equipment manufacturers and
suppliers.
C. Rollover NCAP
Comments regarding NHTSA's rollover program are grouped into the
following categories: Rollover Risk Model and Dynamic Rollover
Structural Test.
1. Rollover Risk Model
Most commenters supported the development of a new rollover risk
model. Several commenters agreed that real-world crash data was
necessary to develop an effective rollover risk model. Specifically,
the Alliance, AIAM, the National Automobile Dealers Association (NADA),
and VW each commented that NHTSA should collect new crash data for
rollover NCAP. In particular, the Alliance and Ford recommended that
the agency collect crash data on both ESC and non-ESC equipped vehicles
to develop a new rollover risk model that better describes rollover
risk for all vehicles, but also accurately reflects the differences
between ESC and non-ESC vehicles. Toyota believed that the update to
rollover NCAP should reflect real-world benefits of ESC on rollover
risk, and that the rollover rating should be combined (with advanced
technologies) into an overall crash avoidance rating. AIAM suggested
that NHTSA consider adjusting a vehicle's rollover risk rating to
reflect the safety benefits of ESC or adopt some other means of
communicating those benefits to consumers.
Recognizing that since such a data collection and analysis cannot
be completed in the near term, Ford, the Alliance and Volvo suggested
that in the near term, an additional rollover NCAP star should be
awarded to those vehicles equipped with an ESC system to recognize the
benefits of ESC. Specifically, the Alliance recommended that NHTSA
provide additional information in the form of a footnote on the
agency's Web site and in the Safer Car brochure that explains the
benefits of ESC and why these benefits warrant an additional star.
2. Dynamic Rollover Structural Test
Some commenters encouraged NHTSA to develop a test for structural
integrity to enhance rollover NCAP. Specifically, Consumers Union,
Public Citizen and ARCCA Incorporated (ARCCA) urged the agency to
consider a dynamic test to assess body structure, seat belt design
(including pretension), side curtain airbags, roof strength, door locks
and retention, and the retention of window glazing. In particular,
Public Citizen believed that a rollover NCAP rating should be based on
a vehicle's ability to resist rollover and to protect occupants in a
rollover crash. They suggested a rating that included ejection as a
consideration since this would provide valuable information about a
vehicle's ability to prevent death or serious injury in a rollover
crash. Additionally, the rating should measure rollover propensity, as
well as crashworthiness measures of performance in a rollover crash.
The Center for Injury Research (CIR) recommended that an NCAP
rollover test be dynamic and somewhat more severe than a dynamic
compliance standard. According to CIR, a dynamic test for use as both a
safety compliance standard and as an NCAP test can and should be
developed simultaneously with action on the roof crush standard.
Moreover, CFA and CAS recommended adding a rollover test with
comparative roof crush tests, while IIHS suggested that NHTSA should
conduct additional research on roof crush. Bidez and Associates stated
that a meaningful rollover crashworthiness test must include roof
deformation, seat belt performance, door opening, and window breakage.
They emphasized that protection should be assessed for front and rear
passengers, adults and children, and that the Jordan Rollover System
(JRS) holds great promise. Conversely, the Alliance, Ford and Nissan
opposed the use of JRS in NCAP. The Alliance commented, and Ford and
Nissan stated at the public meeting that there has been no JRS tests
conducted with an instrumented dummy and therefore, the JRS test
results cannot be related scientifically to the real-world risk of
injury in a rollover crash.
D. Rear Impact
Comments regarding NHTSA's rear impact NCAP activity are divided
into the following categories: Basic Information, Links to the IIHS,
and Dynamic Test.
1. Basic Information
Commenters presented similar views on how NHTSA should provide
consumers with basic information concerning rear impact crashes in an
NCAP publication. GM, Toyota, Subaru and VW supported the inclusion of
information on the proper adjustment and utilization of head restraint
systems. Additionally, GM supported consumer education that included
material such as safety tips and safe driving practices.
2. Links to the IIHS
The IIHS endorsed the agency's proposal and offered their head
restraint evaluation information for posting on the agency's Web site.
Toyota believes that the IIHS results are only one way to assess rear
impact performance, and thus the agency should be cautious and thorough
when determining what rear impact evaluation should be part of a future
NCAP evaluation. They also stated that ample consideration should be
given to passive and active head restraint concepts in order to
maintain benefits from all design types.
The Alliance felt that NHTSA's proposal did not seem consistent
with the principle of the Federal government independently generating
all NCAP data. Rather, they advocated that the agency should
investigate further the injury mechanism of whiplash and then choose
which responses to evaluate based on biomechanics. Similarly, GM
discouraged NHTSA from implementing this option. According to GM, links
to the IIHS Web site might imply that NHTSA has given full endorsement
of IIHS methodology and interpretations, and some consumers may even
conclude that IIHS is a government agency.
3. Dynamic Test
The Alliance believed that NHTSA should first evaluate potential
effectiveness and safety benefits prior to incorporating a rear crash
rating into NCAP. Consumers Union stated that rear impact whiplash
injuries are debilitating to those involved and cause a large cost to
society. Consumers Union recommended that NHTSA look at IIHS's work on
rear impact testing to determine whether developing NCAP ratings for
rear impact results would be cost effective. Public Citizen suggested
that the agency develop a rear-impact crash NCAP rating, especially at
speeds of 35 to 40 mph (56 to 64 kmph) to improve rear-impact occupant
protection and seat back strength. Furthermore, ARCCA stated that rear
impact testing for fuel integrity should be utilized, and that this
type of testing would enable the agency to assess occupant kinematics
and interactions in rear impacts.
Nissan recommended that NHTSA harmonize with the global technical
regulation (GTR) dynamic test
[[Page 40022]]
procedure.\10\ GM stated that the development of a dynamic test by
NHTSA should be considered only after recent revisions to FMVSS No. 202
are assessed. According to GM, if the regulatory changes are shown to
be effective in mitigating injury, a rear impact NCAP could be better
directed toward areas not fully addressed by the current regulation.
Similarly, while Subaru did not support new requirements for FMVSS No.
202a in the short term, they asserted that NHTSA needs to educate
consumers on the proper use and adjustment of head restraints. However,
Subaru believed that in the long term, NHTSA should focus on the study
of whiplash-type injury mechanisms and applicable countermeasures.
---------------------------------------------------------------------------
\10\ See http://www.unece.org/trans/doc/2007/wp29/WP29-143-23r1e.doc. This is an agreement to begin work on Phase 2 of this
GTR, which will analyze a revised dynamic test procedure
incorporating the BioRID-II dummy.
---------------------------------------------------------------------------
E. Crash Avoidance Technologies
Comments regarding NCAP information on crash avoidance technologies
are grouped into three categories: Program Implementation, Selected
Technologies, and Rating System.
1. Program Implementation
Most commenters encouraged NHTSA to implement a new component into
NCAP to rate vehicles on the presence of crash avoidance technologies.
They agreed that such a program would help educate consumers about
these technologies and encourage manufacturers to include them in more
vehicles. According to Ford, the first step would be to identify
promising technologies with measurable real-world safety benefits.
Next, those items must be assessed using developed performance based
metrics, and finally, the assessments should be used to develop crash
avoidance NCAP ratings that balance rating flexibility with stability.
GM emphasized an overarching principle that crash avoidance NCAP
should be biased toward including features that have a high likelihood
of improving safety. GM suggested further that the agency consider a
wording revision, perhaps to `Collision Avoidance and Post-Crash Safety
(CAPS)' NCAP so that a technology such as Automatic Collision
Notification could be considered and included.
Honda encouraged NHTSA to consider a program that would define the
various crash avoidance technologies. They stated that these
definitions should be based on the effect each function of a particular
system has from the driver's point of view, and include a clear
explanation of the actions the system can take to enhance safety.
Honda, along with Delphi, suggested the development of assessment-
weighting coefficients derived from a system's expected benefits and
the frequency of the crash type (using appropriate U.S. databases) that
the system is supposed to address.
BMW suggested a program that would accomplish the agency's goals
without over-promising consumers on expected performance and avoid
crediting systems prematurely. They suggested a program that would
differentiate technologies with real-world effectiveness from those
whose effectiveness numbers were generated by some other means. They
also suggested that NHTSA and manufacturers collaborate on ways to
educate consumers on emerging technologies with promising capabilities
and proven benefits.
Mercedes-Benz (Mercedes) recommended that NHTSA work with the
automotive industry before developing crash avoidance ratings. To
develop future ratings they, along with Continental Automotive Systems,
supported the idea of creating an advisory panel that represents the
viewpoints of all manufacturers competing in the U.S. market.
Nissan agreed with the agency's desire to implement this new
program. They also stated that the agency should identify immediately
its priority technologies through a press release, on the NCAP Web
site, through the ``Buying a Safer Car'' brochure, and on each
vehicle's NCAP summary Web page.
IIHS and NADA were not convinced of the need for NCAP crash
avoidance ratings at this time. IIHS suggested that NHTSA should not
rate vehicle crash avoidance technologies, since the agency cannot
currently identify which systems are most effective.
2. Selected Technologies
Nissan and Delphi agreed with the three technologies selected by
the agency. However, GM and Toyota believed that there were additional
crash avoidance technologies that should be promoted because they would
provide safety value to consumers. For brevity, we chose not to list
them all in this document, but they included such things as daytime
running lights, backover prevention technology, and advanced collision
notification. GM further believed that there were data for some of
these crash avoidance technologies and methods by which potential
benefits could be assessed, and they could be included in the initial
implementation of a crash avoidance NCAP. GM felt that limiting crash
avoidance technologies to the three identified by the agency would
unnecessarily limit the potential safety benefits to consumers.
3. Rating System
a. Cumulative Rating (NHTSA's Approach 1)
There was little support for NHTSA's proposed Approach 1. In the
short term, only Nissan supported a simple cumulative rating whereby
each priority technology would be weighted the same. Both the Alliance
and GM were opposed to this approach. GM believed that a cumulative
rating would not discriminate among the three technologies, and they
would prefer that NHTSA weight appropriately safety-enhancing features
based on their relative benefits. The Alliance stated that the
effectiveness of the selected technologies was not equal, and providing
equal weighting would significantly mislead the consumer as to their
relative safety benefits.
Rather than a star rating or the use of a cumulative rating, BMW
suggested a ``thumbs up'' rating system to assist consumers in quickly
and intuitively distinguishing among technologies on the basis of
maturity. BMW believed that this approach would deliver to consumers
two levels of information: which technologies have the potential for
success and which technologies have a history of success. Furthermore,
BMW felt that this approach would reduce the need for NHTSA to
research, analyze and document the actual benefits of a technology.
Mercedes believed that NCAP should issue publications that would rank
the merits of emerging technologies in a manner similar to that used in
the IIHS status reports, and that NHTSA should communicate with the
industry so that public safety messages could be coordinated with
industry advertisements.
b. Effectiveness Rating (NHTSA's Approach 2)
Nissan, in the long term, along with Toyota, Volvo, Public Citizen,
AORC, the Alliance, AIAM and GM favored the agency's proposed Approach
2 of establishing an effectiveness rating for crash avoidance
technologies. Toyota, however, believed that it would be ideal to
develop information related to each new technology's safety potential
and to establish a ``Graduated Comprehensive Crash Avoidance Rating
System'' concept. They also recommended
[[Page 40023]]
further study to expand the list of technologies beyond ESC, lane
departure warning and forward collision warning to include systems such
as rear pre-collision preparation/warning, emergency stop signal, blind
zone alert, vehicle-to-vehicle and vehicle-to-infrastructure
communications.
F. Presentation of NCAP Information
Comments regarding the presentation and dissemination of NCAP
focused mainly on a combined crashworthiness rating. A few commenters
offered suggestions on the dissemination of NCAP information. NADA
suggested that NHTSA develop, maintain and make available a database of
non-agency sources of credible vehicle safety information. The CAS and
CFA suggested that the agency implement additional and more
sophisticated systems that deliver safety information at the point of
sale. They believed this information should be beyond the agency's new
NCAP labeling program (no examples were given).
Combined Crashworthiness Rating
Most responders to the NCAP notice expressed support for an overall
crashworthiness rating that combined the results from all the crash
modes (front and side) tested. However, IIHS cautioned that an all-
encompassing single rating may allow some poor performance qualities to
be hidden under the umbrella rating. Therefore, they urged NHTSA to
provide consumers with all of the scores in each crash mode to allow
them to choose which vehicle to purchase. Additionally, Delphi, Public
Citizen and Bidez and Associates noted that while a single overall
crashworthiness rating would simplify information for consumers, it
could also confuse consumers if not based on sound science.
Toyota believed there is merit to combining ratings for
crashworthiness evaluations to provide the consumer with a
comprehensive summary of the crash performance of the vehicle in front
and side impacts. They recommended weighting the injuries and
assessment in each impact condition by the distribution of serious
injuries (AIS3+) and fatalities. After determining the weighting
factors for each injury, each impact configuration should receive
similar ``Field Relevance Weighting'' based on frequency, severe injury
risk, and occupancy. Because of the small number of fatalities in NASS,
Toyota suggested exploring FARS augmented with the Multiple Cause of
Death (MCOD) database.
Honda supported a combined crashworthiness rating that covers a
wide variety of real-world collisions. Honda recommended compatibility
testing that assesses performance in crashes between two vehicles with
different geometries and/or weights. Further, they recommended
weighting coefficients for each region of the crash test dummy,
representing specific types of injuries, based on real-world crash and
injury data.
The Alliance generally supported the concept of a combined
crashworthiness rating. They believed that it is possible to combine
the different body regions into a single star rating for both frontal
and side. However, they noted that the frontal NCAP ratings are
vehicle-weight dependent while the side NCAP ratings are generally
weight independent. Thus, the Alliance asserted that a combined
crashworthiness rating would be comparable only within vehicle weight
class. Moreover, AIAM urged NHTSA to ensure that a single rating is
meaningful in terms of real-world performance to drive safety
improvements in all crash modes. They recommended that changes to the
star system be considered only if based on appropriate research
involving consumer surveys or focus groups, and not on intuitive
judgments about what data presentation is most effective.
Public Citizen supported a single rating if it were weighted with
respect to saving lives and preventing injuries. They also suggested
that NHTSA use a letter grade rating system instead of ``stars.''
Volkswagen believed that the agency should consider a single crash
rating only until a crash avoidance NCAP rating grows in substance and
scope. Delphi expressed that a combined crashworthiness rating would
obscure safety benefits; rather, they supported a Euro NCAP style point
system and recommended that key performance-based assessments be
presented as the primary information and that feature-based indicators
be presented as of secondary importance.
G. Manufacturer Self-Certification (of NCAP Results)
With regards to manufacturers providing their own NCAP test
results, GM and Toyota supported the implementation of a type-approval
program wherein NHTSA would oversee NCAP testing conducted by the
manufacturer. GM felt that NHTSA's attendance (or the presence of a
NHTSA representative) would allow appropriate scrutiny of the testing
and ensure consumer confidence in such a program. Additionally, they
strongly discouraged implementation of any program that could
compromise NHTSA-sanctioned vehicle ratings because of results obtained
through spot-checking (presumably conducted by NHTSA). Bidez and
Associates, Consumers Union and Public Citizen urged NHTSA to consider
a manufacturer self-certifying process in which the industry would test
and rate its own vehicles and undergo spot checking of their test
results by NHTSA. According to these commenters, the benefit of such a
program would be to disseminate NCAP test information on newly-
introduced vehicles more rapidly than under the current system.
H. Other Suggestions
In addition to the approaches that NHTSA had proposed to further
enhance its NCAP crashworthiness and crash avoidance activities,
commenters submitted other recommendations to the agency. These
comments on other possible approaches to improving NCAP are grouped
into the following categories: Child Restraints and Rear Seat Testing,
Lighting, and Pedestrians.
1. Child Restraints
Public Citizen suggested that NHTSA incorporate a dynamic child
restraint system (CRS) test into NCAP in all crash modes (including
frontal, rollover, side and rear crashes). They recommended that a six-
year old Hybrid III dummy be restrained in a backless booster and a 5th
percentile female Hybrid III dummy be placed in a 3-point belt in both
rear-outboard seating positions. ARCCA recommended adding instrumented
child dummies to the outboard-designated seating positions in the rear
to investigate issues associated with accommodations and crash
performance of rear-seated occupants resulting from cargo.
Bidez & Associates asserted that the agency should build upon and
leverage the experience of EuroNCAP in child protection to force design
innovation in rear seat safety for six to twelve-year olds.\11\ They
believed there was a need to enhance frontal impact protection of nine
to twelve-year old children who are properly belted in the rear seat.
Their research for restrained nine to twelve-year old children
suggested that rear seat occupants had a risk of serious injury 78
percent higher than that of front seat occupants. They estimated that
the overall injury rate for all restrained nine to twelve-year olds in
all crash types was 38 percent higher in the rear seat than in the
front seat. As such,
[[Page 40024]]
Bidez & Associates recommended that NHTSA immediately warn consumers,
retract its message to parents about placing children in the rear, and
force the automobile industry to upgrade the safety of the rear
occupant area of the existing and future vehicle fleet.
---------------------------------------------------------------------------
\11\ The commenter did not provide specific detail as to what
design innovations have occurred as a result of the EuroNCAP
activity.
---------------------------------------------------------------------------
Subaru, GM and the Alliance opposed implementation of a CRS test
into NCAP. GM asserted that there can be no meaningful dynamic NCAP
test for CRS until there is a meaningful way to tie a CRS NCAP
performance rating to real-world performance. They believed that it is
inappropriate to invent a test and claim correlation to real-world
safety performance improvements without sound data to back this claim.
These commenters felt that using child safety seats in NCAP vehicle
tests would confound the test results and would not lead to a
meaningful vehicle or CRS rating. Additionally, the Alliance asserted
that the real-world safety benefits of child restraints demonstrate the
children are already very well-protected in the rear seat. As such,
they believed that adding child dummies in child restraints to the rear
seating position for front or side NCAP testing would not maximize
advancements in child protection.
Volvo suggested that if the agency wanted to develop a child
restraint test, then the test should be performed on a sled, and they
asserted that there should be improvements in FMVSS No. 213. According
to Volvo, the restrictions for design and testing of the restraints, as
set up in this standard, basically prohibit innovative concepts with
improved performance for reducing misuse and improper installation and
for improving safety performance in a crash. To improve child safety,
Consumers Union recommended that NHTSA pursue research toward an NCAP
rating on (rear) vehicle visibility since they believed that data from
Kids and Cars and others suggest that children are most at risk from
poor visibility and blind zones around the vehicle.
2. Rear Seat Testing
Adding rear seat dummies into the frontal NCAP program was
encouraged by some commenters. In particular, AORC and Bidez and
Associates suggested the addition of the 5th percentile female or the
10-year old dummy. However, AORC asserted that an analysis of field
data would be needed to determine the most appropriate dummy and
seating position, and that dummy development may be required in this
area to better measure abdominal injuries that may be present among
belted occupants in the rear seat.
Individual commenter Mr. Todd Saczalski recommended rear seat
testing with adult and child dummies and child restraints to assess the
difficulty exiting the vehicle and to examine injuries due to seat back
failure. The Children's Hospital of Philadelphia (CHOP) stated that the
agency should place an older belt-restrained dummy, such as the six or
ten-year old Hybrid III child dummy, in the rear seat of the NCAP
frontal test to better understand rear restraint systems for child
occupants. Additionally, they encouraged the use of a belt-positioning
booster seat with the six-year old Hybrid III dummy.
Subaru did not support adding dummies to the rear seating position.
Subaru stated that it might not be possible, with the current front
seat positioning procedure, to properly position a 50th percentile male
Hybrid III dummy in the rear seat of some vehicles; the result could be
inconsistent performance evaluations across all vehicles.
3. Lighting
Some public commenters expressed concerns about lighting and glare
related to daytime running lights (DRLs). However, the glare comments
were focused on the agency's rulemaking activity and not its consumer
information activity. Therefore, daytime running lights are not
discussed in this notice. GM stated that numerous field effectiveness
studies conducted throughout the world show that DRLs could prevent
some crashes. Citing an analysis of field data suggesting that under
daytime conditions, daytime running lights can prevent 5 percent of
opposite direction crashes and 12 percent of pedestrian and
pedalcyclist crashes, GM encouraged NHTSA to expand the installation of
DRLs and include this technology in its crash avoidance rating so that
manufacturers will be encouraged to install them and provide additional
collision avoidance benefit.
4. Pedestrians
Consumers Union recommended that NHTSA study the work of auto
safety researchers in other countries to determine whether a
pedestrian-friendly NCAP rating would be effective in the United
States. Consumers Union noted that Honda has taken a leadership role in
designing a dummy for testing pedestrian safety and designing its
vehicles with pedestrian safety in mind. They urged NHTSA to consider
using the Honda pedestrian dummy and to pursue other opportunities to
improve pedestrian safety. Public Citizen encouraged NHTSA to issue a
pedestrian NCAP test and an accompanying safety standard. They also
challenged NHTSA to follow the lead of the rest of the world by taking
a far more aggressive stand against the dangers vehicles pose to
pedestrians and to raise the bar for pedestrian safety in its
discussions for a Global Technical Regulation (GTR) on pedestrian
safety.
IV. Discussion and Agency Decision
A. Frontal NCAP
In the comments to the notice and the public hearing concerning
enhancements to frontal NCAP, most manufacturers and vehicle safety
advocates supported the retention of the current frontal crash test
protocol at 35 mph (56 kmph). Additionally, several comments suggested
that NCAP injury criteria and metrics be consistent with FMVSS No. 208.
Most responders favored using the KTH injury metric (after additional
research) but also encouraged the inclusion of other injury criteria
such as neck and chest deflection. Some commenters suggested that the
agency immediately evaluate lower leg injuries with the Thor-Lx dummy,
while others recommended that NHTSA harmonize with Japan and Euro NCAP
on lower leg assessments. The agency's analysis and decisions on
frontal NCAP are grouped by categories: Test Dummies, Injury Criteria
and their associated Risk Curves, and Lower Speed Testing.
Test Dummies
Comments pertaining to the adoption of additional test dummies
included wide support for the 5th percentile female Hybrid III dummy,
including its placement in the right front seating position. Others
recommended that the agency include a 95th percentile male Hybrid III
dummy in frontal NCAP. It was also suggested that dummies be placed in
the rear seat for the purpose of rating vehicles.
In response to these comments, NHTSA has decided to include the 5th
percentile female Hybrid III dummy in the right front passenger seating
position. GM provided the most compelling evidence, and the agency
reexamined its own data and reached the same conclusion.\12\ That is,
the real-
[[Page 40025]]
world data suggest that the smaller females were at greater risk and
more likely to be seated in the right front position in frontal
crashes. The agency believes that this dummy's incorporation into the
NCAP frontal program is reflective of real-world crash conditions.
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\12\ The agency's analysis found, based on NASS-CDS estimates
from 1997-2006, that the risk of AIS 2+ injury for smaller belted
occupants in the right front passenger seating position is 33%
greater than that of a mid-sized adult belted occupant in the same
seating position in full frontal crashes (0-40 delta velocities,
non-rollover cases, age ranges from 13 years old or older, height
for small adult: Less than 65 inches, and height for mid-sized
adult: 65-73 inches).
---------------------------------------------------------------------------
NHTSA has chosen, however, not to include the 95th percentile male
Hybrid III dummy in frontal NCAP at this time. The 95th percentile male
Hybrid III dummy has not been evaluated for robustness,
reproducibility, and repeatability in laboratory impact conditions and
it has only undergone very limited sled and vehicle testing. As such,
we believe additional research and testing with this dummy is necessary
before it can be included into frontal NCAP.
With regards to placing adult dummies in the rear seating positions
of frontal NCAP tests, NHTSA believes that more analysis is needed
before a rating program that includes rear seat occupants can be
established. The agency has conducted some limited testing with both
the 50th and 5th percentile Hybrid III adult dummies in the rear seat
under a full frontal impact condition. However, these preliminary
results did not correlate to findings in the real-world and additional
research is necessary to better understand the results.\13\ Similarly,
none of the commenters that suggested an NCAP rating program for the
rear seat provided the necessary data to establish how such a program
would lead to meaningful improvements in safety.
---------------------------------------------------------------------------
\13\ Kuppa, S., Saunders, J., Fessahaie, O., Rear Seat Occupant
Protection in Frontal Crashes, Paper No. 05-0212, Nineteenth ESV
Conference, Washington DC (2005).
---------------------------------------------------------------------------
The agency has decided not to incorporate the use of the lower legs
from the Thor dummy to evaluate lower leg injuries into the program at
this time. The agency is awaiting the completion of research currently
in progress by an SAE task group. Additionally, this tool has not
undergone the necessary robustness, reproducibility, and repeatability
testing that the agency believes is necessary for incorporation into an
NCAP ratings program.
Injury Criteria and Risk Curves
With regards to frontal NCAP injury criteria, the agency agrees
with the commenters and has decided to include all of the FMVSS No. 208
body regions into the frontal NCAP rating system. As suggested by many
commenters, the agency believes that their inclusion will not only add
to the robustness of vehicle evaluations, but it will make the criteria
used to assign NCAP frontal ratings consistent with those used in FMVSS
No. 208 and in other frontal-crash vehicle assessment programs. It will
also allow the agency to incorporate all safety concerns related to
injury criteria readings into the calculation of the frontal rating
thus eliminating the need to use the safety concern symbol.\14\
However, unlike the current NCAP program which uses chest acceleration
to assess thoracic injury risk, the new frontal program will focus
instead on peak chest deflection instead. We believe that the inclusion
of chest deflection into frontal NCAP will encourage development of
restraint systems that will further reduce the risk of thoracic
injuries.\15\ This is especially true given a manufacturer's compliance
margin with the chest acceleration limit of 60 G's and the fact that
the FMVSS No. 208 belted test is now conducted at the same speed as the
frontal NCAP test. Accordingly, frontal NCAP will include the following
body regions and injury criteria: Head (HIC15), neck (Nij,
tension, and compression), chest (deflection), and femur (axial force).
The risk curves that will be used for these criteria are described
below.
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\14\ A safety concern symbol is a test occurrence that is not
reflected in a vehicle's star rating but that NHTSA feels is of
significant importance that the event should be communicated to
consumers.
\15\ The agency evaluated new MY 2005-2007 tested vehicles and
found that for acceleration, the standard deviation for risk of
injury was approximately 3% compared to chest deflection
which was approximately 4%.
---------------------------------------------------------------------------
As indicated in our proposal, NHTSA is also adopting AIS 3+ and AIS
2+ injury risk curves to assess the risk of injury to front seat
occupants.\16\ This approach is different from the current NCAP rating
system which uses AIS 4+ (severe) injury risk curves. The new risk
curves will focus vehicle performance on more frequently occurring
injuries than severe (AIS 4+) or critical (AIS 5+) injuries.
---------------------------------------------------------------------------
\16\ Details of these injury risk curves are provided in
Appendix C, Injury Risk Curves for the NCAP Combined Crashworthiness
Rating System.
---------------------------------------------------------------------------
With the exception of chest deflection, the AIS 3+ injury risk
curves that will be used by the agency in NCAP are the same as those
used for FMVSS No. 208. The AIS 3+ chest deflection injury risk curve
that the agency will use in NCAP was developed in 2003 by Laituri et
al.\17\ The agency chose this risk curve for deflection because, as
noted by the agency during the FMVSS No. 208 advanced air bag
rulemaking, the chest deflection risk curve published by the agency was
not used to establish the performance limits currently in FMVSS No.
208.
---------------------------------------------------------------------------
\17\ Laituri, T., Prasad, P., Sullivan, K., Frankstein, M.,
Thomas, R. (2005), Derivation and Evaluation of a Provisional, Age
Dependent AIS 3+ Thoracic Risk Curve for Belted Adults in Frontal
Impacts, SAE Paper No. 2005-01-0297.
---------------------------------------------------------------------------
The agency will be using an AIS 2+ risk curve for the femur because
most femur fractures are either of the AIS 2 or AIS 3 injury severity.
Additionally, the AIS 2+ femur risk curve was primarily developed from
multi-fragmentary patellar fractures, which, like other articular
surface injuries, are associated with a high level of disability. As
such, using an AIS 2+ injury risk curve will help ensure that
debilitating multi-fragmentary patellar fractures are addressed.\18\
---------------------------------------------------------------------------
\18\ See Ore, L., Tanner, B., States, J. (1993), Accident
Investigation and Impairment Study of Lower Extremity Injury, SAE
Paper No. 930096, SAE International Congress and Exposition,
Detroit, MI, and MacKenzie, E. (1986), The Public Health Impact of
Lower Extremity Trauma, SAE Paper No. 861932, Symposium on
Biomechanics and Medical Aspects of Lower Limb Injuries, San Diego.
---------------------------------------------------------------------------
NHTSA has decided not to incorporate an advanced KTH risk curve
into frontal NCAP at this time. In consideration of the comments
received and because this risk curve is undergoing additional
evaluation, the agency felt it would be premature to include it in
NCAP. However, we do believe that the inclusion of a femur injury
criterion, as indicated above, will lead to improved bolster design.
Similarly, when coupled with the other injury criteria for chest
deflection and neck, will lead to overall improved restraint system
designs. NHTSA has also decided not to harmonize its NCAP femur injury
values with those of EuroNCAP and Japan NCAP. The agency evaluated the
rating schemes of these international programs along with that from the
IIHS. These programs use a sliding scale to rate vehicles as opposed to
injury risk curves. As such, as will be explained later in this
document, because we have chosen to maintain our current methodology
for combining injury risk we cannot substitute sliding scales for risk
curves.\19\
---------------------------------------------------------------------------
\19\ The sliding scales in these programs relate injury measures
to point values without equating them to probability of injury.
However, risk curves equate the injury measures to expected risks of
injury.
---------------------------------------------------------------------------
The injury risk curves used in the NCAP frontal crash test program
for the 50th percentile male Hybrid III and 5th percentile female
Hybrid III dummies
[[Page 40026]]
are shown below. How these injury risk curves will be combined to
generate a vehicle's frontal NCAP star rating will be discussed later
in Section IV-F.
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[[Page 40027]]
[GRAPHIC] [TIFF OMITTED] TN11JY08.001
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Lower Test Speed
A lower test speed for frontal NCAP was supported by some
commenters but an almost equal number opposed such an NCAP test. In
light of the real-world studies conducted by the agency and some of the
commenters, NHTSA has decided that additional research is necessary to
fully address the proposal for a lower test speed. At this time, the
agency has insufficient data with respect to test speed, injury
mechanisms, dummy biofidelity, and risk curves to proceed.
B. Side NCAP
Most commenters supported the agency's proposal to incorporate an
oblique pole test into the program, with several suggesting that this
test should be adopted after the completion of the FMVSS No. 214 phase-
in. Additionally, several responses encouraged the adoption of new test
dummies for side NCAP including WorldSID, SID-IIs and ES-2re dummies.
Commenters also suggested that side impact test procedures and injury
criteria be consistent with FMVSS No. 214. Finally, IIHS encouraged
NHTSA to adopt or modify their current moving deformable barrier (MDB).
The agency's analysis and decisions on side NCAP are grouped into the
following categories: MDB Design, MDB Test Speed, Oblique Pole Test,
Test Dummies in the MDB and Oblique Pole Tests, and Injury Criteria and
their associated Risk Curves.
[[Page 40028]]
MDB Design
The agency has decided against any modifications to the existing
moving deformable barrier. Instead, we will evaluate the IIHS MDB
(including the crabbed vs. perpendicular configuration) as part of a
more comprehensive approach that is currently underway. This research
will help the agency decide what properties a new MDB should have. As
noted in the FMVSS No. 214 Final Rule,\20\ initiatives to improve
vehicle compatibility between passenger cars and light truck vehicles
in side crashes are likely to change the characteristics of striking
vehicles in the future.\21\ As such, we believe these new
characteristics should be included in any upgraded MDB.
---------------------------------------------------------------------------
\20\ 72 FR 51908, Docket No. NHTSA-2007-29134.
\21\ 69 FR at 27992, Docket No. NHTSA-2004-17694.
---------------------------------------------------------------------------
MDB Test Speed
There was little support for an increased test speed for side NCAP,
while some urged the agency to maintain or lower the current speed. As
indicated in our request for comments, the real-world data indicates
that the current test speed is largely representative of real-world
crashes in which serious and fatal injuries occur; yet, increasing the
test speed by 5 mph (8 kmph) would capture approximately 5,000 more
serious and fatal injuries. No commenters disagreed with this data.
However, NHTSA has not conducted any testing at this increased test
speed with the ES-2re or SID-IIs dummies, and we want to better
understand what countermeasures would be developed if the test speed in
side NCAP were increased to 43.5 mph (71 kmph) or higher. As such,
NHTSA has decided to maintain the current test speed and we will
evaluate the test speed as part of our more comprehensive research work
that is already underway.
Oblique Pole Test
Most commenters supported incorporating an oblique pole test into
NCAP. However, some opposed this proposal, stating that a pole test
would not add an incentive for manufacturers to provide additional head
side impact protection beyond the IIHS side impact test. The agency
does not agree with these commenters. As we stated in the FMVSS No. 214
Final Rule, we believe that the pole test in conjunction with our
current MDB will drive better head, chest and pelvis protection than
conducting the IIHS side impact test alone. Recent pole tests conducted
on vehicles that were found to have ``Good'' or ``Acceptable''
performance in the IIHS barrier test had dummy head and pelvis injury
readings, for some vehicles, that were significantly higher than the
IIHS test indicated.\22\ These test results indicate that the use of
the oblique pole test in NCAP will demand more robust countermeasure
designs leading to higher levels of safety performance.
---------------------------------------------------------------------------
\22\ See Appendix A, NCAP and IIHS Pole Test Results.
---------------------------------------------------------------------------
Because the pole test can evaluate only one seating position at a
time, most commenters were in support of running one pole test. Several
stated that conducting multiple side impact pole tests with different
sizes of dummies would introduce significant test burden. We have
decided to add the oblique pole test procedure specified in the FMVSS
No. 214 Final Rule for all vehicles tested by NCAP. Therefore, rather
than conducting a pole test for each outboard seating position in the
vehicle, we will conduct only one test to evaluate the front seat
outboard performance of vehicles. NHTSA believes that a single pole
test with one dummy will provide consumers with information on side
pole performance without introducing significant test burden to both
NHTSA and manufacturers.
Test Dummies in the MDB and Oblique Pole Tests
Outside of those commenters who suggested use of the World SID,
most commenters supported the incorporation of the new, recently
federalized side impact crash test dummies into side NCAP. Some
specifically proposed that the agency use the 50th percentile male ES-
2re dummy for the driver seating position and the 5th percentile female
SID-IIs dummy for the rear seating position in the MDB test. For an
oblique pole test, most encouraged the use of the SID-IIs dummy in the
driver seating position.
Several commenters recommended that the agency incorporate the
WorldSID dummy into Part 572 and side NCAP. For both test
configurations (pole and MDB), the agency has decided not to
incorporate this dummy into NCAP at this time. Although the agency has
been conducting testing and evaluation to determine the suitability of
incorporating the WorldSID into Part 572 and side impact crash tests,
further work remains to be completed before its use in NCAP can occur.
Test dummy selection for the MDB and the pole test are discussed
below.
a. MDB Test
NHTSA has decided to incorporate the new 50th percentile male ES-
2re dummy into the driver seating position and the 5th percentile
female SID-IIs dummy in the rear seating position for the MDB test as
adopted in the FMVSS No. 214 Final Rule. The agency selected the 50th
percentile male ES-2re dummy in the driver position because its weight
and height is more representative of the average driving population
than is the SID-IIs dummy. The 5th percentile SID-IIs dummy was
selected for the rear seating position because it is closer in height
to the average outboard rear seat occupant than the 50th percentile ES-
2re dummy, and its placement in the rear seat will lead to a more
demanding test.\23\
---------------------------------------------------------------------------
\23\ In the testing which supported the FMVSS No. 214 upgrade,
both the 5th and the 50th percentile dummies passed the MDB test but
the rear was more stringent and difficult for the 5th percentile
dummy.
---------------------------------------------------------------------------
b. Oblique Pole Test
NHTSA has decided to conduct only one oblique pole impact test with
the 5th percentile female SID-IIs dummy in the driver position. As
stated in our recent FMVSS No. 214 Final Rule, small stature drivers
(height up to 5 feet 4 inches) comprise approximately 28 percent of
seriously or fatally injured drivers in narrow object side impacts. In
addition, real-world crash data suggests that small stature occupants
have a higher proportion of head, abdominal, and pelvic injuries and a
lesser proportion of chest injuries than median stature occupants.
So while we selected the 50th percentile dummy for the front
seating position in the MDB test (because it represents the average
driver), for the pole test we are selecting the 5th percentile dummy as
the driver because in collisions with narrow objects, the 5th
percentile has the higher risk of injury. Additionally, since we are
conducting the MDB test with the 50th percentile dummy in the driver
seating position and the 5th percentile dummy in the driver seating
position for the pole test, manufacturers will have to encompass a
broader range of seating positions with their vehicle and restraint
system designs.
Injury Criteria and Risk Curves
As with frontal NCAP, several commenters stated that the injury
metrics used in NCAP should be consistent with the safety standard that
serves as their basis. In the case of side NCAP, the safety standard is
FMVSS No. 214. Several commenters stated that
[[Page 40029]]
the adoption of the 50th percentile male ES-2re and 5th percentile
female SID-IIs dummies and their associated injury criteria from FMVSS
No. 214 would facilitate a more comprehensive assessment of side impact
injury. NHTSA agrees with these commenters and has decided to
incorporate head (HIC36), chest (deflection), abdomen
(force), and pelvic (force) injury criteria as well as applicable risk
curves to rate vehicles for the ES-2re and, consistent with the safety
standard, HIC36 and pelvic (force) for the SID-IIs
dummy.\24\ NHTSA believes that these criteria and their inclusion in
side NCAP will lead to a more robust rating. Similarly, it will also
allow the inclusion of head- and pelvic-related injury criteria in the
calculation of the side rating without the need for the safety concern
symbol. Similarly, the injury risk curves that the agency will use in
side NCAP are the same as those used for the recent upgrade to FMVSS
No. 214.\25\
---------------------------------------------------------------------------
\24\ We note that for the SID IIs, we are not incorporating
spine acceleration at this time. Even though this measure is
included in the new FMVSS No. 214, we do not have a risk curve that
has been validated at this time to include in our rating scheme for
rating vehicles for side impact protection.
\25\ Details of these injury risk curves are provided in
Appendix C, Injury Risk Curves for the NCAP Combined Crashworthiness
Rating System.
---------------------------------------------------------------------------
The table below presents the applicable injury criteria and
associated injury risk curves for each dummy that will be used in the
side NCAP vehicle rating. How these injury risk curves will be combined
to generate a vehicle's side NCAP star rating will be discussed later
in Section IV-F.
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[[Page 40030]]
[GRAPHIC] [TIFF OMITTED] TN11JY08.002
[[Page 40031]]
[GRAPHIC] [TIFF OMITTED] TN11JY08.003
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Lead Time
While most commenters supported the inclusion of the pole test in
NCAP, an almost equal number suggested that the test not be
incorporated until after FMVSS No. 214 is fully phased-in. NHTSA does
not agree with these commenters. NHTSA believes that some manufacturers
have begun to design vehicles to meet the pole test and we want
consumers to be aware of those vehicles. Additionally, we believe that
conducting the pole test for MY 2010 will provide an incentive for
others to begin and/or accelerate their processes for improvement as
well. Finally, rating vehicles on both their performance in the pole
test and the MDB test, which will now incorporate HIC and other
criteria, will help foster an environment for vehicle manufacturers to
design better side impact designs for the head, chest and pelvis, and
allow consumers to make more informed choices based on these new tests.
C. Rollover NCAP
Several commenters suggested that the agency add an additional star
to the Rollover NCAP rating for vehicles equipped with ESC. They
suggested the extra star be supplemented by a footnote saying,
``equipped with electronic stability control.'' In addition, one
commenter suggested that a star be subtracted from vehicles not
equipped with ESC. Commenters also recommended that NHTSA incorporate a
new, dynamic structural test into rollover NCAP. The agency's analysis
[[Page 40032]]
and decisions regarding NHTSA's rollover program are grouped into two
categories: Rollover Risk and Injury Risk Models and Dynamic Rollover
and Structural Test.
Rollover Risk and Injury Risk Models
With regards to the agency's proposal to develop a new rollover
risk model, the agency agrees with commenters' concerns about the
effects of ESC on the rollover risk model. However, we do not agree
that is appropriate to add or subtract a star in the rollover rating to
account for ESC. The current rollover rating is the result of a
detailed analysis of a vehicle's potential risk of rollover if a crash
is initiated. Given that the star bands are set at 10 percent, adding a
star to the rollover risk rating could suggest to consumers that ESC
would reduce a particular vehicle's risk of rollover by up to 10
percent in a given crash. This could result in unsupported and
inaccurate vehicle ratings.
The current rollover risk model was fit using crash data collected
several years ago (at a time when ESC was available in relatively few
vehicles). We are monitoring the fit of the model to newer data and, in
particular, to data for ESC-equipped vehicles. We have identified 7,000
single-vehicle crashes with NCAP-tested vehicles equipped with ESC in
our State Data System (SDS). At this time, the current model appears
consistent with the newer data, possibly (at least in part) because of
the sampling variability associated with the relatively small ESC
subset. A larger sample may produce different results, and we will
recalibrate the estimates if we determine conclusively (that is, beyond
the effects of statistical variability) that the current estimates do
not describe the newer data. In the meantime, we will continue to use
the risk estimated from the vehicle's Static Stability Factor (SSF) and
its propensity to tip up in the dynamic rollover ``fishhook'' test as
described in 68 FR 59250 (October 14, 2003). These are provided below:
[GRAPHIC] [TIFF OMITTED] TN11JY08.007
Where SSF=static stability factor
This model describes the absolute risk of rollover given a single-
vehicle crash.
As will be discussed later, we will include ESC in the new NCAP
Crash Avoidance Rating. We feel this will be much more effective in
highlighting the importance of ESC and other potentially life-saving
technologies.
Dynamic Rollover and Structural Test
In their public hearing testimony, Ford suggested that NCAP dynamic
rollover protocol be aligned with compliance protocol for ESC to
minimize the risk of unintended consequences from the program. The
agency does not agree with this suggestion. These tests have
significantly different performance requirements and are intended to
measure different dynamic vehicle responses. In the future, it may be
possible to address the likelihood of aligning the new ESC compliance
test with the NCAP dynamic rollover ``fish-hook'' test, but additional
research is needed before these two tests can be combined. Neither test
measures the responses from the other test; therefore, neither test
could be used as a substitute for the other.
Some commenters suggested a structural rollover test; in
particular, NHTSA received comments regarding the Jordan Rollover
System (JRS) test device.\26\ Some commenters believe that the JRS test
can be conducted with dummies to demonstrate whether vehicle roof
performance meets objective injury and ejection criteria for belted and
unbelted occupants. As part of our roof crush upgrade, the agency has
received numerous comments regarding the JRS device.\27\ The JRS and
other dynamic rollover procedures are being addressed as a part of the
roof crush rulemaking currently underway. Therefore, a decision on its
appropriateness for incorporation into NCAP would be premature at this
time.
---------------------------------------------------------------------------
\26\ The JRS device rotates a vehicle body structure on a
rotating apparatus (``spit'') while the road surface moves along the
track and contacts the roof structure.
\27\ See Docket No. NHTSA-2005-22143.
---------------------------------------------------------------------------
D. Rear Impact
With regards to rear impact NCAP, some commenters urged the agency
to include a rear impact crash test rating and/or the IIHS test results
in NCAP. Others indicated that linkage to IIHS could appear to be an
agency endorsement of the IIHS testing and that it would be premature
to incorporate a new rear impact dynamic test into NCAP since the
effect of the new FMVSS No. 202a requirements is unknown at this
time.\28\ Rather, they suggested that NHTSA educate consumers on the
proper use and adjustment of head restraints.
---------------------------------------------------------------------------
\28\ By MY 2012, 100% of front and rear seats will have to meet
the upgraded FMVSS No. 202a.
---------------------------------------------------------------------------
NHTSA does not agree that a dynamic test would be premature at this
time since such an option exists in our FMVSS No. 202a. However, we do
agree with the commenters that providing the IIHS results on our Web
site could lead to consumers believing that the agency has approved, in
particular, their dynamic test procedure. In addition, we note that the
test dummy used by IIHS has not been approved for regulatory use, and
some of the injury criteria used for this assessment have not been
correlated with real-world injury.
We also see very little benefit to consumers in publishing IIHS's
static head restraint ratings of Good, Acceptable, Marginal, etc. on
http://www.safercar.gov. The agency's upgraded head restraint
regulation (FMVSS No. 202a) will begin an 80% phase-in for front seats
in MY 2010. Any manufacturer certifying their head restraint to the
static option of FMVSS No. 202a, according to IIHS's current scheme,
would be placed in the Good or Acceptable category. Most of those not
achieving a Good rating will be adjustable head restraints that IIHS
downgrades by one category simply because they are adjustable. Thus,
there would be very little meaningful difference in the rating.
For those manufacturers certifying their head restraints to the
dynamic option in FMVSS No. 202a, the static IIHS rating would not
provide a meaningful metric of performance. The agency also
contemplated publishing the actual numerical values of static height
and backset that the IIHS measures but have decided against this
course. We believe that consumers would find this information confusing
[[Page 40033]]
and difficult to interpret. As such, rather than providing the IIHS
data on our Web site, we have decided to update http://www.safercar.gov
to include information related to proper head restraint adjustment.
E. Crash Avoidance Technologies
Most commenters supported the agency's proposal to implement a
crash avoidance ratings program. However, there were two commenters who
did not believe that a crash avoidance rating program was needed at
this time. Two commenters suggested that NHTSA work with the automotive
industry to create an advisory panel to develop a crash avoidance
rating system. Additionally, most responses did not favor a cumulative
rating system; instead, several commenters emphasized the importance of
selecting advanced technologies and developing a rating system based on
real-world effectiveness. Furthermore, several commenters recommended
that the agency consider other advanced technologies beyond ESC, FCW
and LDW.
NHTSA agrees that a rating system that incorporates a crash
avoidance system's estimated benefit is ideal. We also believe that we
should establish this new program quickly for two reasons. First, we
want to draw a greater distinction for consumers regarding vehicles
that are being equipped with ESC during the phase-in period. Second, in
addition to ESC, there are other new safety technologies which exist
today that can assist a driver in preventing severe and frequently
occurring crashes. We believe that through NCAP, we can provide an
incentive to encourage accelerated deployment of these new, advanced
technologies. The agency's analysis and decisions on new crash
avoidance ratings program are grouped into the following categories:
Selected Technologies and Rating System.
Selected Technologies
Those commenters who supported establishment of a program that
would promote crash avoidance technologies agreed with the agency's
selection of ESC, FCW and LDW as beneficial technologies. Others
believed that the agency should expand its list to encompass crash
avoidance, crashworthiness and post-crash technologies so as not to
limit the potential safety information that could be provided to
consumers. NHTSA believes that ESC, FCW and LDW are the only
technologies that meet the agency's criteria and are mature enough for
inclusion in a crash avoidance rating program. That is, all three have
available benefits data and performance test procedures to be included
in a rating program.
We believe that both FCW and LDW will address major crash problems
seen on U.S. roadways. FCW is designed to address primarily rear-end
crashes, which account for approximately 30 percent of all crashes,
while LDW is designed to address crashes due to unintended lane drift.
Crash types that may result from lane drift include road departure and
opposite direction crashes. The NCAP report showed that rear-end road
departure, and opposite direction crashes represent a significant
amount of the total maximum AIS 3+ injuries.\29\ Results from large
scale field tests for FCW and LDW provided effectiveness and benefit
information for each technology and suggest that FCW and LDW have the
potential to significantly reduce the number of crashes that occur in
the U.S.\30\
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\29\ See http://www.safercar.gov/newcarassessmentenhancements-2007.pdf at page 18, Table 6.
\30\ LDW effectiveness estimated from data included in NHTSA
Report No. DOT HS 810 854, Evaluation of a Road Departure Crash
Warning System, December 2007. FCW effectiveness estimated from data
included in NHTSA Report No. DOT HS 810 569, Evaluation of an
Automotive Rear-End Collision Avoidance System, March 2006.
---------------------------------------------------------------------------
Additionally, NHTSA used data from these field operational tests
(FOTs), as well as additional agency research, to finalize performance
tests establishing minimum performance criteria for FCW and LDW so that
vehicles can be rated on their presence.\31\ For ESC, because it had
been in the field for some time, we used real-world data to establish
effectiveness and then used the test procedure which accompanied the
Final Rule (FMVSS No. 126) to develop a performance test and minimum
performance criteria.\32\ The table below presents NHTSA's
effectiveness estimate values for ESC, FCW, and LDW.\33\ A range was
used for LDW to reflect potential system availability variation due to
lane marking quality.
---------------------------------------------------------------------------
\31\ See Docket No. NHTSA-2007-27662 for ESC, LDW, and FCW test
procedures.
\32\ See NHTSA Report No. DOT HS 810 794, The Statistical
Analysis of the Effectiveness of Electronic Stability Control (ESC)
Systems-Final Report, July 2007. See also 72 FR 17236, Docket No.
NHTSA-2007-27662.
\33\ See Appendix B, Effectiveness Estimates for ESC, FCW and
LDW for a summary explanation of how overall effectiveness estimate
values were generated.
Effectiveness Estimates for ESC, FCW, and LDW
------------------------------------------------------------------------
Effectiveness
System (percent)
------------------------------------------------------------------------
ESC................................................... 59
FCW................................................... 15
LDW................................................... 6-11
------------------------------------------------------------------------
NHTSA believes that the FOT results for FCW and LDW are applicable
for estimating real-world safety benefits since these technologies were
evaluated in the same real-world driving environment in which they
would be deployed. In general, in an FOT, the major variables impacting
a technology's safety benefits, including differences in individual
driving styles and behavior, system performance, and driver acceptance,
are taken into account. Likewise, critical safety incidents (i.e. near-
crash incidents that occur during the FOT) data are recorded and
evaluated to determine if the technology provided a safety benefit in
terms of critical incident reduction. Assuming a proportional
relationship between near-crash events and actual crashes, critical
incident data are further evaluated using statistical methods to
estimate crash reduction benefits. In the field tests for FCW and LDW
systems, NHTSA provided technical management and the Volpe National
Transportation Systems Center performed an independent evaluation to
estimate safety benefits which included rigorous statistical analysis.
NHTSA believes that ESC, FCW and LDW are the only crash avoidance
technologies that meet the agency's criteria for inclusion in a crash
avoidance rating program at this time. That is, all three address a
major crash problem, safety benefit projections have been assessed, and
performance tests and procedures are available to ensure an acceptable
performance level. The agency acknowledges that many other technologies
were identified by commenters such as collision mitigation braking
systems, lane keeping assist systems, and side object detection
technologies. However, at this time the agency does not have enough
data to estimate the safety benefits of these systems, and therefore
will not promote these other technologies at this time.
Through our current research activities and/or information obtained
from the automotive industry and the public, the agency anticipates
that it will gain information on the benefits and performance
capabilities of other advanced safety technologies. If the agency
anticipates making changes to the rating system or the technologies
that the agency has chosen to promote
[[Page 40034]]
as that information is gathered, the agency will seek public input on
the appropriateness of such changes. At this time, we anticipate using
similar criteria (addresses a major crash problem, assessed safety
benefits, and established performance tests and procedures) to
determine technologies for future program inclusion.
Rating System
Generally, there was little support for a crash avoidance rating
system based on a cumulative concept (e.g., the more technology you
have; the higher the rating). Instead, several commenters preferred
that the agency develop a rating system based on a computation of
benefits to be expected from the crash avoidance technologies of a
rated vehicle. Regardless of approach, these commenters all suggested
that the agency use a star rating system to inform consumers about the
presence of advanced technologies. BMW and Mercedes suggested a simpler
approach whereby technologies would essentially be listed without
regards to their effectiveness and without summing them into an overall
rating crash avoidance rating. BMW offered an approach where all
technologies would all be treated equally but where those technologies
that had been proven beneficial by real world studies would somehow (in
their scheme solid green and hollow thumbs were used) be denoted
differently. Similarly, Mercedes suggested a simple ranking system for
technologies.
To gauge consumer understanding and acceptance of these various
systems, NHTSA tested the cumulative approach, the effectiveness
approach, and the list approach with groups of consumers.\34\ NHTSA
conducted four focus group sessions in the DC area with participants
who had to qualify as either a primary or shared decision maker with
respect to automobile purchases for their household and intended to
purchase a new or used automobile in the next two years. Participants
in both groups were also screened to ensure they had some level of
concern about the safety of automobiles and the groups represented a
mix of age, education, and income. The agency tested letters, stars,
words, check marks, and color schemes (for standard and optional
availability) depending on which one of the three approaches was being
tested. The agency also tested a subset of these treatments in an on-
line forum.
---------------------------------------------------------------------------
\34\ The full study report is available http://www.regulations.gov in Docket No. NHTSA-02004-19104.
---------------------------------------------------------------------------
With regards to what type of rating system should be used,
participants overwhelmingly preferred a rating system that was a simple
list approach. Additionally, focus group participants unanimously
agreed that the use of colors is not visually appealing to fully
comprehend what they are viewing. In the treatments tested by the
agency, single check marks as opposed to multiple check marks to
indicate a technologies importance were preferred by most participants.
Additionally, to display and communicate the information, consumers
stated that a single check mark or the use of text (indicating standard
or optional) is the most understandable way to illustrate the presence
of crash prevention technologies, though neither marking was
overwhelmingly preferred.
Participants overwhelmingly objected to the multiple checks, star
markings and A-D grading scale, saying they were very difficult to
understand, despite having an associated key. Several participants also
stated that if there were a technology or several technologies that
were more important than the others, than that should be specifically
communicated or noted on the layout and inferred, not the use of stars,
individual letter grades, or multiple check marks.
The agency believes that the preference for the use of check marks
or text over the use of an effectiveness approach may be rooted in the
fact that participants (and to the extent that they are reflective in
general of new car buyers) may not fully grasp the importance of these
features. For example, participants generally stated that they think of
these features as ``nice to haves'' rather than ``must haves'' because
they are not yet aware of how the features can reduce fatalities. As
such, the agency intends to continue monitor the public's understanding
of this new rating program and if necessary change the way in which
ratings are communicated to the public. For now, based on these focus
group results, the agency will use text to communicate the standard or
optional presence of ESC, LDW, and FCW on vehicles.
F. Presentation and Dissemination of Safety Information
Some commenters encouraged the agency to disseminate additional and
more sophisticated consumer information but no specific examples were
given. Most commenters discussed and supported the agency's proposal
for a combined crashworthiness rating. The agency's analysis and
decisions on the presentation and dissemination of safety information
are divided into the following categories: Presentation of Safety
Information and Combined Crashworthiness Rating.
Presentation of Safety Information
Some commenters supported consumer education materials such as
safety tips and safe driving practices. Others suggested that NHTSA
develop, maintain and make available a database of non-agency sources
of credible vehicle safety information. Finally, some commenters
suggested that the agency provide additional information at the point
of sale (beyond that required by the new labeling program). NHTSA
agrees with many of these suggestions. NHTSA continuously investigates
ways to improve marketing the NCAP vehicle ratings program. We will
place the results of our enhanced marketing studies in Docket No.
NHTSA-02004-19104, as they are completed.
Combined Crashworthiness Rating
Most commenters supported an overall crashworthiness rating that
combined the results from all test conditions. Honda and Toyota
provided some details but GM and Ford provided very specific
information on how this new rating could be calculated. Some commenters
cautioned that an overall rating would overly simplify information for
consumers, and that it could mislead consumers if poor performance were
hidden under an umbrella rating. Given the general support for an
overall rating and the public's desire for simpler information, NHTSA
is implementing a new overall crashworthiness rating that combines the
results of the front, side and rollover programs.
NHTSA will provide a summary crashworthiness rating for each
vehicle (which we will call the Vehicle Safety Score) plus individual
scores for each occupant in each crash condition for that vehicle (as a
set of relative risk measures). This is in accordance with comments
from Delphi, Public Citizen, Bidez and Associates, and the IIHS who
expressed concern over individual test results being masked and that
individual scores in each crash mode should continue to be provided to
the consumer. Scores for vehicles will be provided to the consumer via
a star rating system where the new bands for 1 to 5 stars were
determined by the mean and dispersion of the risk of injury in each
crash test condition (front and side) and the risk of rollover.
Although NHTSA's previous proposal did not suggest including the
rollover risk rating in the crashworthiness rating, the agency has now
decided to do so.
[[Page 40035]]
The agency's decision to include the rollover rating in the combined
rating is consistent with the 1996 Transportation Research Board
recommendation,\35\ and we believe that its inclusion provides a more
complete summary rating. Below, we describe how the frontal and side
scores are developed and how these scores are combined with the
rollover score to create an overall score.
---------------------------------------------------------------------------
\35\ See Transportation Research Board, Shopping For Safety:
Providing Consumer Automotive Safety Information. TRB Special Report
248 (1996).
---------------------------------------------------------------------------
Consistent with what has already been presented, NHTSA has selected
the following test conditions, test dummies and injury criteria to
develop its combined rating:
One frontal impact crash test (full frontal rigid barrier
crash test at 35 mph (56 kmph)) with a 50th percentile male Hybrid III
dummy in the driver position and a 5th percentile female Hybrid III
dummy in the front passenger seating position.
One side impact crash test (38.5 mph (62 kmph) with
NHTSA's moving deformable barrier (MDB) crabbed at 27 degrees into the
side of vehicle) with an ES-2re dummy in the front seating position and
a SID-IIs dummy in the rear seating position on the struck side of the
vehicle.
An oblique pole impact test (20 mph (32 kmph)) at 75
degrees into a 25 cm diameter pole including the SID-IIs dummy in the
front seating position.
Dynamic maneuvering (fish-hook) rollover test and static
stability factor (SSF).
All applicable injury criteria.
Use of injury risk curves.
a. Combining Injury Risk From Different Body Regions
The agency has chosen to maintain its current method for combining
injury metrics for any seating position in its test. That is, the risk
of injury to each body region are assumed to be independent events and
can be statistically combined to determine the joint probability of
injury to the occupant using the following equation: p(A or B) =
p(A)+p(B)-p(A)*p(B) where A and B are the independent events. Using
injury risk curves for different body regions, this method results in
an overall risk of injury for the occupant. For the two adult Hybrid
III dummies there are four independent events to combine, which are
injury risk to the head, neck, chest, and femur/knee. For the ES-2re
dummy, there are also four independent events, which are injury risk to
the head, chest, abdomen, and pelvis, while for the SID-IIs dummy,
there are only 2 independent events which are injury risk to the head
and pelvis.
In GM's proposal, the normalized injury measures for different body
regions are combined by weighting each by the proportion of injuries
associated with each injury measure. The result of this method does not
represent either an absolute injury risk or a relative injury risk (as
in NHTSA's method). Therefore, the risk levels of different vehicles
are not quantifiable. In addition, Ford stated that GM's proposal
assumes a linear relationship between the dummy response and injury
risk, when generally the relationship is non-linear. Therefore, Ford
expressed that GM's proposal could result in an inaccurate estimation
of the relative vehicle safety performance. NHTSA agrees with this
assessment and has chosen to use the joint probability of injury
formula, as it does now, to combine injury risks to different body
regions for an occupant. However, the agency notes that computation of
the joint probability requires there to be quality data available for
all of the injury risks being combined. Similarly, to compute the
overall summary rating, data must also be available from all of the
tests to prevent a model from not being rated. As such, the agency has
included redundant sensor measurement capability in the test dummies
(where possible), grouped tests (front, side, and rollover) together,
and worked with our test labs to ensure that they are using the most up
to date calibration procedures. In this way, we hope to alleviate the
potential loss of data and subsequently, vehicles with incomplete
ratings.
b. Risk of Injury by Seating Position and Test Condition
For each vehicle, the risk of injury is estimated from six test
results, which are: (1) Driver in frontal crash, (2) passenger in
frontal crash, (3) driver in side MDB crash, (4) rear seat passenger in
side MDB crash, (5) driver in oblique pole impact, and (6) rollover
potential in single-vehicle crashes using rollover test results. Ford
suggested that the agency combine results using a simple average, but
GM suggested a weighted approach to combine results.
To combine the risk of injury by occupant seating position, GM
suggested weighting based on occupant demographics and the relative
frequency of exposure by seating position. Ford commented that this
approach would undervalue NCAP test results for passengers since the
proportion of drivers is far greater than that of passengers. Ford
asserted that this method of obtaining the overall injury risk might
confuse consumers who seek a broader assessment of safety performance
than one limited to the driver. Ford proposed using the straight
average of the risks of injury for the driver and the passenger to
obtain the overall injury risk. NHTSA agrees with Ford's suggested
approach.
However, rather than use the percentages calculated from the
probability of injury results (as is currently done), NHTSA will be
computing the relative risk for each seating position and each test
condition. This relative risk measure provides an estimate of an
occupant's risk of injury compared to a baseline injury risk. The score
for each occupant in each test condition is computed by dividing the
overall risk of injury in each test condition by a baseline risk of
injury. As will be explained below, the baseline risk of injury in each
test condition is an approximation of the fleet average injury risk for
that test condition. The baseline risk of injury is set once and reused
for subsequent model years. This allows cross-year comparisons with
future fleets.\36\ This operation results in six summary scores for
each vehicle representing the relative risk of injury for the driver
and passenger in the frontal crash test and side MDB test, the driver
in the oblique pole test, and the relative risk for all occupants in
rollovers with respect to a baseline injury risk. As such, the scores
indicate how a particular vehicle compares to a baseline risk and these
are the scores (star ratings) that will be presented to consumers on
the Web site and in agency publications.
---------------------------------------------------------------------------
\36\ In the future, the baseline could be adjusted to reflect
vehicle designs. However, the agency would seek public input on the
issue before such an adjustment would occur.
---------------------------------------------------------------------------
To compute a vehicle's overall risk of injury in frontal crash
tests, NHTSA has decided to use the simple average of the probability
of injury to the driver and front passenger. The risk of injury to the
driver in side crashes is calculated as the weighted average of the
combined probability of injury of the driver in the MDB test (weighted
by 80 percent) and that of the driver in the oblique pole test
(weighted by 20 percent). The weights reflect the proportion of belted
driver fatalities in real-world crashes represented by the MDB and pole
tests in MY 1999 and newer vehicles (FMVSS No. 214 Final Rule, Docket
No. NHTSA-2007-29134). The overall risk of injury in side crashes is
then computed as the average of the risk of injury to the driver in
side impacts (weighted average from MDB and pole test results) and the
probability of injury to the rear seat
[[Page 40036]]
passenger in the MDB test. For rollover, in order to combine the risk
from the rollover test with the risk of injuries obtained from the
crash test, the agency has assumed that a belted occupant in a single-
vehicle crash p(roll) has the same relative risk of injury as the risk
of rollover given a single vehicle crash.
As suggested in Ford's proposal, NHTSA is adopting this method of
averaging the risk of injury between the driver and the passenger to
obtain an overall injury risk for each crash mode to ensure equal
weighting for all seating positions. This is unlike GM's approach of
applying significantly higher weight to the driver than the passenger
based on occupancy rates in each seating position. NHTSA believes that
GM's proposal would not encourage manufacturers to offer advanced
safety systems to all seating positions, thereby resulting in reduced
protection to some. This is especially significant in the side MDB
crash test where the SID-IIs dummy in the rear seat generally
demonstrates a higher risk of injury than the driver. Under GM's
approach, the rear seating position would have far less value than the
driver seating position because the rear seat has a relatively low
occupancy rate. However, when combining the pole test results with the
MDB results for the front seat, we do believe that weighting by crash
test condition is appropriate. In this way, the results from the pole
tests are proportional to their occurrence and do not mask a vehicles
performance in the MDB test, possibly providing an inaccurate portrayal
of the vehicle.
The figure below graphically illustrates the method of combining
the different risks.
BILLING CODE 4910-13-P
[[Page 40037]]
[GRAPHIC] [TIFF OMITTED] TN11JY08.004
BILLING CODE 4910-59-C
c. Combined Crashworthiness Rating
The agency's combined crashworthiness rating, the Vehicle Safety
Score (VSS), is computed as the weighted average of the three summary
scores for front, side, and rollover. The weight factors applied (\5/
12\ for frontal crashes, \4/12\ for side crashes, and \3/12\ rollovers)
reflect the proportion of injuries for belted occupants (in vehicles of
model year 1999 and later) in each crash mode.\37\ This approach is
similar to GM's proposal of combining the crash test results using a
weighted average.
---------------------------------------------------------------------------
\37\ These model years were chosen to reflect newer vehicle
designs and to obtain a statistically robust trend from the NASS/CDS
data.
---------------------------------------------------------------------------
Since the NCAP frontal crash test involves a vehicle with a fixed
rigid barrier, it represents a crash between two vehicles of the same
weight. Therefore, the safety rating from the NCAP frontal crash test
and the combined crashworthiness rating (which includes the frontal
crash test results) depends on vehicle mass, and cannot be compared
across vehicle weight classes. In contrast, on an individual basis, the
side crash (pole and MDB) test results and the rollover results can be
compared across vehicle classes.
[[Page 40038]]
d. Determination of Baseline Risk and Star Bands
NHTSA will continue to use the star rating system to provide an
individual crashworthiness rating for each seating position, each crash
mode, and their combination. However under the new system, stars will
be interpreted differently. Bands for 1 to 5 stars were determined by
the mean and dispersion of the risk of injury in all three test
conditions (front, side, and rollover).
In the NCAP frontal tests, the average risk of injury to the driver
in all 2008 model year vehicles is 15 percent 5 percent.
Based on our NCAP injury data for the 50th percentile male seated in
the right front passenger seat, we expect that a 5th percentile seated
in that same seating position would have a similar distribution.
Therefore, the agency selected a baseline injury risk of 15 percent to
compute the frontal relative risk scores. A relationship between
relative risk of injury and the number of stars assigned was developed
using the existing NCAP frontal crash test data for the 50th percentile
male Hybrid III dummy in the driver seating position.
To determine the star bands for frontal NCAP, NHTSA selected a
baseline risk of 15 percent (representing the average risk of injury to
the driver in MY 2008 vehicles in the NCAP frontal crash test) to serve
as the break point for the 4 star and 3 star rating. Other criteria
used to determine the star bands were (1) vehicles performing
exceptionally well (At 0-15 percentile of vehicles tested) are assigned
a five star rating, and (2) Vehicles performing very poorly (greater
than 4 standard deviations from mean) would be assigned a one star.
Attempts were also made to maintain equidistant star band boundaries.
Based on these criteria and the distribution of the relative risk of
injury scores of MY 2008 vehicles, the relationship between the
Relative Risk Score (RRS) and the number of stars was established, and
is presented below. The RRS is computed by (1) rounding the injury risk
to the nearest tenth of a percent in accordance with the rounding-off
method of ASTM Standard Practice E 29 for Using Significant Digits in
Test Data to Determine Conformance with Specifications, (2) dividing
the injury risk by 0.15 (15.0 percent baseline injury risk), (3) and
finally rounding the result to the nearest one hundredth in accordance
to ASTM Standard E 29.
As with frontal NCAP, this same methodology was applied to the
scores in the side MDB and oblique pole tests as well as the combined
crashworthiness Vehicle Safety Score. The agency found, for a limited
number of newer vehicles tested to both the MDB and Pole test, that
when the MDB test results were combined with the pole test, the average
risk was 15%. As such, for side NCAP, the combined crashworthiness
rating also represents the relative risk of injury with respect to an
injury risk of 15 percent.
Relationship Between the Relative Risk and the Star Bands for Front and Side Crash Tests Using 15 Percent Risk of Injury as the Fleet Average
--------------------------------------------------------------------------------------------------------------------------------------------------------
5 stars 4 stars 3 stars 2 stars 1 star
--------------------------------------------------------------------------------------------------------------------------------------------------------
RRS Values......................... RRS < 0.67............ 0.67 <= RRS < 1.00 1.00 <= RRS < 1.33 1.33 <= RRS < 2.67. RRS >= 2.67.
Probability........................ P < 0.100............. 0.100 <= P < 0.150 0.150 <= P < 0.200 0.200 <= P < 0.400 P >= 0.400.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Similarly for rollover, we selected a baseline risk of 15 percent
for the risk of rollover, which produces the relative risk measures
shown below.\38\
---------------------------------------------------------------------------
\38\ See Appendix D, Probability of Injury, Vehicle Safety
Score, and the Star Rating System.
Current NCAP Star Rating in Rollover and Its Relationship With the Relative Risk in Rollover Using 15 Percent
Risk of Injury as the Baseline
----------------------------------------------------------------------------------------------------------------
Number of stars Risk of rollover Relative risk score in rollover
----------------------------------------------------------------------------------------------------------------
1 star............................. P >=0.40............................. RRS >=2.67.
2 stars............................ 0.30 <=P <0.40....................... 2.00 <=RRS <2.67.
3 stars............................ 0.20 <=P <0.30....................... 1.33 <=RRS <2.00.
4 stars............................ 0.10 <=P <0.20....................... 0.67 <=RRS <1.33.
5 stars............................ P <0.10.............................. P <0.67.
----------------------------------------------------------------------------------------------------------------
G. Manufacturer Self-Certification
Several commenters suggested that NHTSA consider a self-
certification process in which NHTSA would oversee the testing
conducted by the manufacturer. However, it seems possible that
manufacturers could run several tests and report only the best results;
or because manufacturers would know exactly what vehicle was being
tested, the vehicle's star ratings might not be indicative of a random
sample (as currently done by the agency). Additionally, because NHTSA
does not currently have the resources to conduct oversight over a
manufacturer's test facility, dummy certification and test setup, a
manufacturer's facilities might take more liberty than agency contract
laboratories in their testing procedures.
These issues do not affect a manufacturer's self-certification of
compliance with the Federal motor vehicle safety standards. A
manufacturer had a legal duty to report any non-compliance promptly to
NHTSA. They must also recall and remedy without charge to the purchaser
any vehicle that fails to comply with an applicable safety standard.
The manufacturer also is subject to additional penalties if it cannot
demonstrate that it had no reason to know, despite exercising
reasonable care, that the vehicle did not comply with the standard.
These are all express provisions of Title 49, Chapter 301 of the United
States Code. There are no
[[Page 40039]]
parallel provisions for the New Car Assessment Program.
In addition, one of the primary reasons for allowing manufacturer
self-certification in NCAP was to allow information about new vehicles
to be provided more quickly. In this case, NHTSA has had an optional
NCAP test program in place for nearly 20 years. This allows
manufacturers to request a test of new or redesigned vehicles and get
the NCAP information out quickly to the public. Given these
considerations, NHTSA is not adopting the suggestions to permit
manufacturer self-certification of NCAP results.
H. Other Recommendations
Several commenters, in their responses to the notice and at the
public hearing, presented other recommendations for the agency's
consideration. NHTSA has decided not to adopt any of these
recommendations at this time for the reasons outlined below.
Compatibility Assessment
Some commenters recommended front-to-front compatibility
assessments, while others suggested vehicle aggressivity evaluations
for frontal NCAP. These commenters did not provide (and NHTSA is not
aware of) any data that would support an NCAP compatibility evaluation
at this time. The agency has a research program in this area and should
a valid compatibility metric emerge from that research, the agency will
consider it at that time.
Child Restraints
Some commenters suggested that the agency test and rate child
restraints either in the vehicle and/or on a sled test. NHTSA has
examined this in the past and at that time concluded that: (1) A
dynamic rating for a child restraint system (CRS) was not feasible; (2)
the agency wanted to focus on ease of use ratings; and (3) limited in-
vehicle testing with a six-year old dummy did not correlate with real-
world data.\39\ However, the agency has continued to investigate CRS
and child dummy performance in the current NCAP test environment, and
their correlation to injury risks for children in real-world crashes.
The agency will take actions at such time as the test results and
analyses can be used to support such a rating program.
---------------------------------------------------------------------------
\39\ See 70 FR 29815, Docket No. NHTSA-2004-18682.
---------------------------------------------------------------------------
Increased Test Speed
Two commenters and most automobile manufacturers stated that
increased test speeds in frontal NCAP would promote stiffer vehicle
designs and more aggressive restraints. NHTSA agrees that without an
appropriate measure of vehicle stiffness, a higher speed test could
lead to more aggressive vehicle designs. Therefore, NHTSA has decided
not to adopt a 40 mph (64 kmph) frontal NCAP test because of concerns
about vehicle compatibility, the lack of test data, and no clear
understanding of potential countermeasures that could be used by
manufacturers to achieve the top rating. In addition, the agency notes
that the current frontal NCAP test speed represents 99 percent of all
crashes, and increasing the test speed would not address a large
portion of real-world crashes.
Lighting
Some commenters recommended that NHTSA incorporate a lighting/
visibility program into NCAP to address vehicle blind spots and glare.
The commenters did not provide (and NHTSA does not believe that there
is) sufficient data to justify incorporating a lighting or visibility
measure into NCAP at this time. The agency is conducting research in
both of these areas to better assess the safety problem and explore
what approaches and/or countermeasures should be considered. Therefore,
NHTSA has decided not to incorporate an NCAP rating for lighting or
visibility at this time.
Frontal Offset Test
Some commenters encouraged the incorporation of a frontal offset
test into frontal NCAP. However, others did not support an offset test
stating that such a test did not provide sufficient benefit to
consumers or that it was already being done by others (e.g., IIHS).
NHTSA has been studying the offset test procedure, but we continue to
believe that further research and analysis is needed to ensure that
improved occupant protection is provided by such a test without
potential unintended consequences such as increased vehicle stiffness
and aggressivity.
Pedestrians
Some commenters encouraged NHTSA to pursue opportunities to improve
pedestrian safety through NCAP. The agency has no pedestrian standard
at this time. While NHTSA is actively engaged in the development of a
Global Technical Regulation on pedestrian safety, we feel it would be
premature to develop a rating program before the details, test protocol
and potential benefits of this activity have been resolved. Therefore,
we are not incorporating pedestrian rating into NCAP at this time.
Frontal Pole Test
A frontal pole test was suggested by two commenters and
specifically opposed by one. While the real-world data presented by the
IIHS seems to imply that a number of fatalities and injuries are
occurring in narrow object frontal impacts, at this time NHTSA is
unclear as to what countermeasures might be developed. Similarly, a
significant amount of research would need to be conducted to establish
a new frontal impact pole test for NCAP. Accordingly, the agency is not
adopting this proposal at this time.
I. Monroney Label
On August 10, 2005, the President signed into law the Safe,
Accountable, Flexible, Efficient Transportation Equity Act: A Legacy
for Users (SAFETEA-LU). Section 10307 of the Act requires new passenger
automobiles to have NCAP safety ratings displayed on the price sticker,
known as the Monroney label. As required by SAFETEA-LU, on September
12, 2006 (71 FR 53572), NHTSA published a final rule implementing this
statutory requirement, including prescribing the form, required
information, and layout of the label. The rule, set forth at 49 CFR
part 575.301, applied to covered vehicles manufactured on or after
September 1, 2007.
Regulation 575.301 specifies the required information for the NCAP
front, side and rollover tests. For the frontal crash, there are two
separate ratings, one for the driver and one for the right front
passenger. Similarly, two separate ratings are established for the side
crash, one for the front seat and one for the rear seat. One rating is
provided for rollover.
Under our regulation, front, side and rollover NCAP ratings must be
placed on new vehicles manufactured 30 or more days after the
manufacturer receives notification from NHTSA of the ratings. As
explained earlier in this notice, in addition to any overall rating,
the agency will still make available on http://www.safercar.gov the
individual seating position results for each crash condition (front,
side pole, and side MDB) and for side NCAP, the front seat and rear
seat score developed from the combination of the pole and MDB test
results. However, the agency is using this notice to inform
manufacturers and other interested persons of our intent to use the new
combined side impact score
[[Page 40040]]
developed from the pole and MDB tests for the Monroney label. In
addition, we will initiate rulemaking to change the format and/or the
layout of the Monroney label to incorporate the new overall combined
crashworthiness rating. We believe that the combined rating and the new
side impact score will provide consumers with the information they need
to make comparative judgments on new vehicles.
When we issue the notice of proposed rulemaking, we will address
relevant issues including changing the layout and format of the label
to incorporate this new, additional information and to address other
labeling issues such as the lead time necessary for the manufacturers
to update their labeling operations.
V. Conclusion
NHTSA will implement these decisions regarding enhancements to NCAP
beginning with MY 2010 vehicles. For that model year, the agency will
make changes to its existing front and side testing activities
requiring all vehicles to be rated using these new protocols. With
regards to the frontal crash test program, NHTSA will maintain the 35
mph (56 kmph) full frontal barrier test protocol but will incorporate
the following body injury criteria: Head (HIC15), neck (Nij,
tension, and compression), chest (deflection), and femur (axial force).
The agency will also add the 5th percentile female Hybrid III dummy in
the right front seating position. For side impact, NHTSA will maintain
the current moving deformable barrier test at 38.5 mph (63 kmph) but
will update that test to include head (HIC36), chest
(deflection), abdomen (force), and pelvic (force) injury criteria for
the ES-2re and, consistent with the safety standard, HIC36
and pelvic (force) for the SID-IIs dummy. For the MDB test, the 50th
percentile male ES-2re dummy will be used for the driver position and
the 5th percentile SID-IIs dummy for the rear seated passenger
position. Additionally, vehicles will also be assessed using a new
oblique pole test and a 5th percentile female dummy in the driver
position, using HIC36 and pelvic (force). For rollover, the
agency will continue to rate vehicles for rollover propensity, but will
wait to update its rollover risk model to allow for more real-world
crash data of vehicles equipped with electronic stability control.
For MY 2010, the agency will also implement a new crash avoidance
program that will rate vehicles on the presence of select advanced
technologies and a new overall Vehicle Safety Score that will combine
the star ratings from the front, side, and rollover programs.
Appendix A
NCAP and IIHS Pole Test Results
NHTSA
--------------------------------------------------------------------------------------------------------------------------------------------------------
Combined
Lower spine acetabulum
Vehicle Vehicle class SAB type Driver test dummy HIC36 accel (Gs) & iliac
force (N)
--------------------------------------------------------------------------------------------------------------------------------------------------------
IARV Limits............ 1000 82 5525
2007 Honda Pilot..................... SUV..................... Curtain + Torso........ SIDIIs................. 3464 68 6649
2007 Nissan Quest.................... Van..................... Curtain................ SIDIIs................. 5694 79 5786
2007 Ford Escape..................... SUV..................... Curtain + Torso........ SIDIIs................. 407 65 6515
2006 VW Passat....................... Medium PC............... Curtain + Torso........ SIDIIs................. 323 40 3778
2006 Subaru Impreza.................. Medium PC............... Combo.................. SIDIIs................. 184 58 4377
2007 Toyota Avalon................... Heavy PC................ Curtain + Torso........ SIDIIs................. 642 62 6672
--------------------------------------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Combined
Driver test acetabulum Overall Head Structure/
Vehicle Vehicle class SAB type dummy HIC15 & iliac rating Head/neck Torso Pelvis/leg protection safety cage
force (N)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
2007 Honda Pilot............... SUV............. Curtain + Torso... SID-IIs...... 167 4700 G G G G G A
2007 Nissan Quest.............. Van............. Curtain + Torso... SID-IIs...... 207 2900 G G G G G A
2007 Ford Escape............... SUV............. Curtain + Torso... SID-IIs...... 216 5600 G G G A G A
2006 VW Passat................. Medium PC....... Curtain + Torso... SID-IIs...... 168 3300 G G G G G G
2006 Subaru Impreza............ Medium PC....... Combo............. SID-IIs...... 325 5100 G G G G G A
2007 Toyota Avalon............. Heavy PC........ Curtain + Torso... SID-IIs...... 350 4100 G G A G G A
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Appendix B
Effectiveness Estimates for ESC, FCW and LDW
Electronic Stability Control (ESC)
This effectiveness estimate comes from the report: Statistical
Analysis of the Effectiveness of Electronic Stability Control (ESC)
Systems--Final Report. Report No. DOT HS 810 794, July 2007.
From the Executive Summary, page vii, for Road Departure--Police
Reported Crashes:
The effectiveness of ESC for passenger cars = 45%
(weighting for the difference in crash reporting among the States).
The effectiveness of ESC for Light Trucks and Vans
(LTV's) = 72% (weighting for the difference in crash reporting among
the States).
Assuming an equal weighting between passenger cars and
LTVs, the average effectiveness = 59% for Road Departure Crashes.
59% was assumed to be a best overall effectiveness estimate for
road departure crashes.
Forward Collision Warning (FCW)
Based on field operational test (FOT) data from the Automotive
Rear-End Collision Avoidance FOT (ACAS FOT) collected from 66
participants who each drove an FCW-equipped vehicle for 3 weeks, it
was estimated that the FCW system has the potential to reduce about
15% of all rear-end crashes. The FCW system integrated rear-end
crash warning function with adaptive cruise control function. This
system becomes operational when vehicle speed exceeds 25 mph and
disengages when the speed falls below 20 mph. The participants
accumulated 98,000 miles of driving data. The FCW system operated in
the background during the first week of the FOT, providing
information about baseline driving. The final 2 weeks of the FOT
generated information
[[Page 40041]]
about driver performance with the FCW system while it operated in
the foreground.
FCW system effectiveness was estimated separately in each of
nine driving conditions based on FOT data, which combined three
driving states (lead vehicle stopped, lead vehicle decelerating, and
slower constant-speed lead vehicle) and three travel speed bins
(<25, between 25 and 35, and >=35 mph). Total system effectiveness
was derived by integrating individual system effectiveness estimates
in the nine driving conditions using corresponding rear-end crash
data from the GES (see Equation (6) in Section 4.2.2.3 on page 4-
70). Based on available FOT data, the FCW has shown crash prevention
potential in lead vehicle stopped at speeds over 25 mph, slower
constant-speed lead vehicle at speeds below 25 and over 35 mph, and
lead vehicle decelerating at speeds over 35 mph (see Table 4-32 on
page 4-73). Using corresponding crash data by travel speed only (not
taking into account crash data by attempted avoidance maneuver),
total system effectiveness was estimated at 95% of all
rear-end crashes (see Figure 4-42 on page 4-74). However, GES crash
data on travel speed are unreliable since the travel speed variable
is coded as ``unknown'' in over 70% of the rear-end crash cases. As
an alternative to travel speed, it is recommended that the posted
limit data be used to break down the rear-end crash data. Thus by
using corresponding crash data by posted speed limit, total system
effectiveness was estimated at 1511% of all rear-end
crashes assuming that crash-involved vehicles were traveling at the
posted speed limits reported in the crash database (see Figure 4-42
on page 4-74). This safety benefit also assumes 100% system
deployment in the vehicle fleet.
15% was assumed to be a best overall effectiveness estimate for
rear-end crash prevention.
Reference
Najm, W.G., Stearns, M.D., Howarth, H., Koopmann, J., and Hitz,
J., ``Evaluation of an Automotive Rear-End Collision Avoidance
System''. U.S. Department of Transportation, National Highway
Traffic Safety Administration, DOT HS 810 569, March 2006.
Lane Departure Warning (LDW)
The overall average crash reduction estimate range (6% to 11%)
for Lane Departure Warning was obtained from data collected during a
Road Departure Collision Warning (RDCW) System Field operational
test (FOT). The system merged and arbitrated warnings between a lane
departure warning system (referred to as a lateral drift warning
function in the study) and Curve speed warning (CSW) function. LDW
monitored the vehicle's lane position, lateral speed and available
maneuvering room. The CSW monitored the vehicle's speed and upcoming
road curvature.
The RDCW Evaluation Final Report \1\ discusses numerous safety-
related benefits that resulted during the treatment period, when the
RDCW alerts were enabled. Most safety benefits were accrued by the
LDW portion of the RDCW system. These benefits include increased
turn signal use, improved lane keeping, and fewer crossings of a
solid lane marker at speeds above 55 mph. However, only one of these
benefits--fewer crossing of a solid lane marker--was used to
forecast a reduction in road-departure crashes. Solid lane markers
serve as the road boundary. During the treatment period and at
speeds above 55 mph, drivers crossed solid lane markers 44 percent
less often than they did in the baseline period, when RDCW alerts
were not enabled. This reduction, weighted by the national departure
crash counts at this speed range, resulted in a forecasted reduction
in road-departure crashes.
Road-departure crash statistics presented in Section 4.1 of the
RDCW Evaluation Report.\1\
Table 4-1.--Road-Departure Precrash Scenarios (Thousands) GES 2003
[Critical event]
----------------------------------------------------------------------------------------------------------------
Departed Lost
Vehicle movement road edge control Other Row totals
----------------------------------------------------------------------------------------------------------------
Count............................... ...................... 261 208 ........... 469
Row Percent......................... Going Straight........ 55.7 44.3 ........... ...........
Percent............................. ...................... 25.4 20.3 ........... 45.7
Count............................... ...................... 116 172 ........... 288
Row Percent......................... Negotiating a Curve... 40.3 59.7 ........... ...........
Percent............................. ...................... 11.3 16.7 ........... 28.0
Count............................... ...................... 65 55 ........... 120
Row Percent......................... Initiating a Maneuver. 54.2 45.8 ........... ...........
Percent............................. ...................... 6.3 5.4 ........... 11.7
Count............................... ...................... ........... ........... 150 150
Percent............................. Other................. ........... ........... ........... 14.6
Count............................... ...................... 442 435 150 1,027
Percent............................. All Groups............ 43.0 42.4 14.6 ...........
----------------------------------------------------------------------------------------------------------------
From section 4.4.1, this results in an estimated 9,372 to 74,844
fewer road-departure crashes each year. The average of this range
equals 42,108. This range is based on full LDW availability.
Effectiveness = collisions avoided/collision population
Collision population originates from two departure road edge
cells in Table 4-1, and equals 377,000 crashes. With full
availability, the effectiveness equals:
[GRAPHIC] [TIFF OMITTED] TN11JY08.008
With the 56% availability observed in the FOT, the estimated
effectiveness estimated is (.56)(.11) = 6%.
Since system availability may vary depending on the quality of
lane markings, a range of 6 to 11% was assumed to be the best
overall effectiveness estimate for crashes caused by lane drift.
Reference
[1] Wilson, B.H., Stearns, M.D., Koopman, J., Yang, D.,
``Evaluation of a Road Departure Crash Warning System''. U.S.
Department of Transportation, National Highway Traffic Safety
Administration, DOT HS 810 854, December 2007.
Appendix C
Injury Risk Curves for the NCAP Combined Crashworthiness Rating System
This Appendix presents the injury risk curves for various body
regions applicable to the Hybrid III 50th percentile male (HIII 50M)
and the Hybrid III 5th percentile female (HIII 5F) dummies in
frontal crash tests and the ES-2re and the SID-IIs side impact
dummies in lateral crash tests.
Injury Risk Curves for Frontal NCAP Head
The head injury criterion (HIC15) as a metric for assessing head
injury risk is well established and in use in FMVSS No. 208
(Eppinger et al., 1999).
[[Page 40042]]
[GRAPHIC] [TIFF OMITTED] TN11JY08.009
Where [Phi] = cumulative normal distribution
The AIS 3+ head injury risk curve from the FMVSS No. 208
Advanced Airbag Final Economic Assessment was extended from the
Hertz (1993) AIS 2+ head injury risk curve using real-world data to
determine the relative incidence of different severity brain
injuries. Since NHTSA will assess the risk of serious or more severe
head injuries, this equation has been selected for use in NCAP
(Equation 1). Due to the uncertainty in the scaling methods, NHTSA
took the conservative approach in estimating head injury assessment
reference values for the HIII 5F dummy. As such, this equation will
also be used to assess the risk of AIS 3+ head injury for the HIII
5F dummies.
Neck
The risk of AIS 3+ neck injury is assessed using Nij (Equation
2) as described in Eppinger et al. (1999, 2000) and currently used
in FMVSS No. 208. The equation below presents the Nij formulation
and Table 1 presents the intercept values (from FMVSS No. 208) of
Fint and Mint used in Nij.
[GRAPHIC] [TIFF OMITTED] TN11JY08.010
Where Fz is the axial force and My is the flexion/extension moment
measured in the upper neck load cell.
Table 1.--Nij Intercept Values and Tension/Compression Limits for In-Position 50th Percentile Adult Male and 5th Percentile Female Dummies
--------------------------------------------------------------------------------------------------------------------------------------------------------
Nij intercepts
Dummy -----------------------------------------------------------------------------------------------------------------------
Tension Compression Tension Compression Flexion Extension
--------------------------------------------------------------------------------------------------------------------------------------------------------
HIII 50M........................ 4170 N............ 4000 N............ 6806 N............ 6160 N............ 310 Nm............ 135 Nm.
HIII 5F......................... 2620 N............ 2520 N............ 4287 N............ 3880 N............ 155 Nm............ 67 Nm.
--------------------------------------------------------------------------------------------------------------------------------------------------------
In general, neck injuries occur due to combination loading to
in-position occupants. As such, the Nij injury risk curve is
applicable and the agency has selected the risk curve used in the
establishment of the Advanced Air Bag rule for FMVSS No. 208 from
Eppinger. The neck tension injury risk curve was developed using the
same paired pig and dummy test data used for the development of Nij.
NHTSA assumed that the tensile neck tolerance is approximately equal
to the compressive neck tolerance. Therefore, the injury risk curve
for neck tension can also be applied to obtain neck injury risk due
to neck compression. Equations 3-5 present the risk of AIS 3+ neck
injury as a function of Nij, neck tension, and neck compression for
the HIII 50M and HIII 5F dummies.
[GRAPHIC] [TIFF OMITTED] TN11JY08.011
Where tension--or--compression is in kV.
The risk of AIS 3+ neck injury in the NCAP frontal crash test is
the greater of the injury risk for Nij, neck tension, and neck
compression. In general, the risk of injury obtained from Nij is
higher than that for neck tension or compression in frontal NCAP
tests.
Chest
Eppinger et al. (1999) developed injury risk curves for chest
deflection. However, the derived injury risk curve was independent
of occupant age and was not adequately adjusted to reflect real-
world chest injury risk. As such, we have chosen to use a more
recent, peer reviewed thoracic injury risk curve using chest
deflection. Laituri et al. (2003, 2005) developed AIS 3+ thoracic
injury risk curves by analyzing published cadaveric sled test data
and then developing a transfer function between dummy chest
deflection measurements and cadaveric chest deflection under similar
impact conditions. The resulting thoracic injury risk curve is based
on dummy measured chest deflection and occupant age and was
evaluated against real world injury risk in frontal crashes. In
order to apply this AIS 3+ thoracic injury risk curve in NCAP, it
was normalized to the average age of the driving population which is
approximately 35 years. The injury risk curve based on this
evaluation for assessing risk of AIS 3+ chest injury is presented in
Equation 6 for the Hybrid III 50th percentile male dummy. The injury
risk curve as a function of chest deflection (Equation 7) for the
HIII 5th percentile female dummy (HIII 5F) is obtained by scaling
the risk curves for the HIII 50M using the scale factor for chest
deflection (=0.817) which is the ratio of the chest depth of a 5th
percentile female to that of a 50th percentile male (Eppinger (1999)
and Mertz (2003)).
[[Page 40043]]
[GRAPHIC] [TIFF OMITTED] TN11JY08.012
Knee-Thigh-Hip
The injury risk curve that the agency will use for the Knee-
Thigh-Hip (KTH) is the same as that reported by Eppinger et al.
(1999) in support of FMVSS No. 208 (Equation 8). The injury risk
curves represent femur and knee injury risk since most of the
injuries in the datasets that were used to develop these injury risk
curves were to the distal femur and knee and only four of the 126
tests used to develop these risks curves produced a hip fracture. In
addition, the knee injuries in this dataset were primarily
multifragmentary patellar fractures, which, like other articular
surface injuries, are associated with a high level of long-term
disability.
The femur injury risk curve as a function of femur axial force
for the HIII 5th percentile female dummy (HIII 5F) was developed by
scaling the risk curves for the HIII 50M using a scale factor of
0.68 (Equation 9). This scale factor was proposed by Eppinger (1999)
and later by Mertz (2003) and is based on the ratio of the thigh
circumference of a 5th percentile female to that of a 50th
percentile male.
[GRAPHIC] [TIFF OMITTED] TN11JY08.013
Joint Probability of Injury
The joint probability of injury to an occupant is obtained by
combining the risk of injury to each body region assuming the injury
to different body regions are independent events. Therefore the
probability of serious injury, Pjoint, is given by:
[GRAPHIC] [TIFF OMITTED] TN11JY08.014
Injury Risk Curves for Side NCAP
The injury risk curves for the side impact dummies, ES-2re and
SID-IIs (Kuppa, 2006), were developed from biomechanical tests
involving human cadaveric subjects and detailed in NHTSA docket
(NHTSA-2007-29134).
Head
The Head Injury Criterion (HIC), used for assessing injury risk
in frontal impacts is based on repeated drop tests of embalmed human
cadavers onto rigid and padded surfaces where the impact area was
the forehead (Lissner et al. 1960, Hodgson et al. 1972). Though
forehead impacts are representative of a frontal impact scenario,
the ECE R95 directive and Euro NCAP continue to apply HIC for head
injury assessment in lateral impact scenarios, implicitly assuming
that the head/brain injury tolerance is independent of loading
direction and impact location. Similarly, NHTSA applied HIC36 to
assess head/brain injuries in lateral crashes in the upgrade to
FMVSS No. 214 so as to harmonize with the existing FMVSS No. 201
optional pole impact test.
Therefore, the FMVSS No. 208 AIS 3+ injury risk function
presented above for the HIII 50M and HIII 5F dummies will be used in
the NCAP side impact tests with the ES-2re and SID-IIs dummies.
However, in order to be consistent with FMVSS No. 214, HIC36 will be
used rather than HIC15 (Equation 10).
[GRAPHIC] [TIFF OMITTED] TN11JY08.015
Where [Phi] = cumulative normal distribution
Chest
The risk of AIS 3+ and AIS 4+ thoracic injury for a 45 year old
(average age of the driving population involved in side impacts)
50th percentile adult male occupant as a function of maximum rib
deflection of the ES-2re side impact dummy was developed by Kuppa
(2006) by considering the injury severity to be a polychotomous
variable (AIS<3, AIS=3, AIS>3). However, this AIS 3+ injury risk
curve has a finite risk of injury even at zero mm of rib deflection.
The same cadaver and dummy test data reported by Kuppa (2006) were
reanalyzed considering the injury severity to be dichotomous (AIS<3
and AIS>=3 or AIS<4 and AIS>=4) to develop new AIS 3+ and AIS 4+
injury risk curves. Since the injury risk curves have not been
adjusted to represent the average risk of injury in real world side
crashes, NHTSA will use the AIS 4+ injury risk curve as the
corresponding AIS 3+ injury risk in NCAP. The risk of AIS 3+
thoracic injury for a 45 year old (average age of the driving
population involved in side impacts) 50th percentile adult male
occupant as a function of maximum rib deflection of the ES-2re for
use in NCAP is presented in Equation 11.
[GRAPHIC] [TIFF OMITTED] TN11JY08.016
[[Page 40044]]
FMVSS 214 final rule does not utilize rib deflection measures of
the SID IIs dummy and so they are not considered in NCAP at this
time. Additionally, because the agency does not have a valid risk
curve at this time for spine acceleration, it is also not included.
Abdomen
The AIS 3+ abdominal injury risk curve using the total force in
the ES-2re abdomen reported by Kuppa (2006) is utilized in NCAP and
is presented in Equation 12.
[GRAPHIC] [TIFF OMITTED] TN11JY08.017
Where F is the total force in the ES-2re abdomen in Newtons.
Since FMVSS No. 214 does not utilize the abdominal rib
deflection measures of the SID-IIs dummy for injury assessment, no
abdominal injury risk assessment will be applied to the NCAP side
MDB test and the oblique pole test using the SID IIs dummy.
Pelvis
NHTSA will utilize the AIS 3+ pelvic injury risk curve (Equation
13) reported by Kuppa (2006) for injury assessment with the ES-2re
driver in the side MDB NCAP test.
[GRAPHIC] [TIFF OMITTED] TN11JY08.018
Where F is the pubic force in the ES-2re dummy in Newtons
Kuppa (2006) developed the risk curve for AIS 2+ pelvic fracture
as a function of the sum of iliac wing and acetabular force in the
SID-IIs by scaling the normalized 50th percentile male data to that
of a 5th percentile female, accounting for older subject age,
adjusting for lower bone tolerance among female occupants, and
transforming the applied force on the cadaver to the sum of
acetabular and iliac force measured in the SID-IIs dummy. This
pelvic injury risk function for the SID-IIs is presented in Equation
14.
[GRAPHIC] [TIFF OMITTED] TN11JY08.019
Where F is the sum of the acetabular and iliac force in the SID-IIs
dummy in Newtons
In developing the pelvis injury criteria for the SID-IIs, an
occupant age of 56 years was considered to correspond to the average
age of AIS 3+ injured occupants (of height less than 5 ft 4 inches)
involved in side crashes. Research has indicated that pelvic
injuries to older occupants are associated with increased mortality
(O'Brien et al. 2002; Henry et al. 2002). During a 5-year period, O'
Brien et al. and Henry et al. examined patients who sustained a
pelvic fracture and found that patients 55 years and older were more
likely to sustain a lateral compression fracture pattern and had a
higher frequency of mortality due to the injury than younger
patients (<55 years old). Due to the higher mortality rate
associated with the elderly, an AIS 2+ injury risk curve is used in
NCAP for the SID-IIs representing a 56 year old small female rather
than the AIS 3+ injury risk specified for the ES-2re dummy
Joint Probability of Injury
The joint risk of injury to an occupant is obtained by combining
the risk of injury to the head, chest, abdomen and pelvis assuming
the injury to different body regions are independent events (as was
done for frontal impact). Note that for the SID-IIs, the risk of
chest and abdomen injury is omitted and only the risk of injury to
the head and pelvis are combined.
[GRAPHIC] [TIFF OMITTED] TN11JY08.020
Injury Risk In Rollover Crashes
The Static Stability Factor (SSF) of a vehicle is defined as
one-half the track width, t, divided by h, the height of the center
of gravity above the road (SSF = t/(2 x h)). Since 2004, the NCAP
vehicle rollover rating has been calculated as a function of the
vehicle's static stability factor and its propensity to tip up in
the dynamic rollover ``fishhook'' test (68 FR 59250). The risk of
rollover in single-vehicle crashes as a function of the static
stability factor and the results of the dynamic rollover test was
estimated from the State Data System and is presented below in
Equations 15 and 16.
[GRAPHIC] [TIFF OMITTED] TN11JY08.021
Where SSF=static stability factor
This model describes the absolute risk of rollover given a
single-vehicle crash. We can also describe the risk of rollover
relative to an ``average'' vehicle. For example, we could use a
``typical'' SSF (which is about 1.35 for the current fleet) for
vehicles that did not tip up in the dynamic test (which reflects the
future in the sense that when all vehicles are equipped with ESC
there will be essentially no tip-ups in the dynamic test). The risk
of rollover for a subject vehicle compared to the risk of rollover
for this baseline case describes how much more or less likely the
subject vehicle is to roll over compared to the baseline. Thus, for
example, a relative risk of rollover of 0.80 means that the subject
vehicle is 20 percent less likely to roll over than the baseline; a
relative risk of 1.25 means that the subject vehicle is 25 percent
more likely to roll over than the baseline. For certain purposes
(specifically, in producing the Vehicle Safety Score as described
elsewhere in this Notice), we treat this as equivalent to the
relative risk that a belted occupant is injured in a rollover crash
given a single-vehicle crash. This is not strictly true, but our
review of the SDS data for belted drivers indicates that it is
approximately true. Therefore, the relative risks of injury to a
belted driver in a rollover crash conditional on being involved in a
single-vehicle crash are approximately proportional to the risks of
rollover outlined above.
REFERENCES
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the Supplemental Notice of Proposed Rulemaking FMVSS No. 208
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6407-40.
Backaitis SH and St. Laurent A. (1986) Chest Deflection
Characteristics of Volunteers and Hybrid III Dummies. Proceedings of
the Thirtieth Stapp Car Crash Conference, pp 157-166. SAE Paper No.
861884.
Bouquet, R., Ramet, M., Bermond, F., Vyes, C. (1998) Pelvic
Human Response to Lateral Impact, 16th International Technical
Conference on the Enhanced Safety of Vehicles, Paper No. 98-S7-W-16,
National Highway Traffic Administration, Windsor, 1998.
Cesari D and Bouquet R. (1990) Behavior of Human Surrogates
under Belt Loading. Proceedings of the Thirty-Fourth Stapp Car Crash
Conference, pp 73-82. SAE Paper No. 902310.
Eppinger et al., (1999) Development of Improved Injury Criteria
for the Assessment of Advanced Automotive Restraint Systems II,
NHTSA Docket No. NHTSA-1999-6407-5.
Eppinger et al. (2000) Supplement: Development of Improved
Injury Criteria for the Assessment of Advanced Automotive
[[Page 40045]]
Restraint Systems II, NHTSA Docket No. NHTSA-2000-7013-3.
Hertz E. (1993) A Note on the Head Injury Criteria (HIC) as a
Predictor of the Risk of Skull Fracture. 37th Annual Proceedings of
the Association for the Advancement of Automotive Medicine.
Hodgson, V.R. and Thomas, L. M. (1972) Effect of Long Duration
Impact on Head, SAE 72096, Sixteenth Stapp Car Crash Conference,
Society of Automotive Engineers, Warrendale, PA.
Horsch JD, et al. (1991) Thoracic Injury Assessment of Belt
Restraint Systems Based on Hybrid III Chest Compression. SAE Paper
No. 912895, Thirty-Fifth Stapp car Crash Conference, pp 85-108.
International Standards Organization (ISO) Working Group 6, ISO
TC 22/SC 12/ WG 6, Road Vehicles--Injury Risk Curves to Evaluate
Occupant Protection in Side Impact, ISO/TR 12350:2002(E).
Kent, R., Patrie, J., Benson, N. (2003) The Hybrid III dummy as
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Forty0Seventh Annual Proceedings, Association for the Advancement of
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Kuppa, S., Eppinger, R. (1998) ``Development of an Improved
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Kuppa, S. (2001) Lower Extremity Injuries and Associated Injury
Criteria, Proceedings of the Seventeenth International Technical
Conference on the Enhanced Safety of Vehicles, Amsterdam, June,
2001.
Kuppa, S. (2006) Injury Criteria for Side Impact Dummies, Docket
No. NHTSA-2007-29134-0001.
Laituri, T., Prasad, P., Kachnowski, B., Sullivan, K., Przybylo,
P. (2003) Prediction of AIS 3+ Thoracic Risks for Belted Occupants
in Full Engagements, Real World Frontal Impacts: Sensitivity to
Various Theoretical Risk Curves, SAE Paper No. 2003-01-1355, 2003
SAE World Congress.
Laituri, T., Prasad, P., Sullivan, K., Frankstein, M., Thomas,
R. (2005) Derivation and Evaluation of a Provisional, Age Dependent
AIS 3+ Thoracic Risk Curve for Belted Adults in Frontal Impacts, SAE
Paper No. 2005-01-0297.
Laituri, T., Henry, S., Sullivan, K., Prasad, P. (2006)
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Lissner, H. R. et al. (1960) Experimental Studies on the
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Appendix D
Relative Risk of Injury, Vehicle Safety Score, and the Star Rating
System
Introduction
The risk of injury to each occupant in NHTSA's Crashworthiness
Rating System is the joint probability of injury to each body region
considered for that occupant. The overall risk of injury in frontal
crashes is the average of the injury risk to the driver and
passenger in the frontal crash test. The risk of injury to the
driver in side crashes is the weighted average of the risk to the
driver in the MDB test (weight=0.8) and the pole test (weight=0.2).
The overall risk of injury in side crashes is the average of the
injury risk to the driver in side crashes (MDB and Pole) and the
injury risk to the rear seat passenger in the MDB test.
The crashworthiness rating system provides relative risk of
injury for each occupant in each crash test condition (driver and
front outboard passenger in the frontal crash test, driver and near
side rear seat passenger in the side MDB test, driver in the oblique
pole impact test, and rollover test) and a Combined Crashworthiness
Rating Vehicle Safety Score. The relative risk of injury in each
test condition for a vehicle is computed by dividing the overall
risk of injury in each crash mode by an average baseline risk (for
example, the average risk of serious injury in the fleet or that of
a group of select vehicles in the fleet for a certain model year).
The Combined Crashworthiness Rating Vehicle Safety Score (VSS) is
obtained as a weighted average of the individual Relative Risk Score
(RRS) in each test condition.
The RRS for each test condition and the VSS represent the risk
of injury to occupants of the vehicle relative to a baseline risk of
injury. For example, a VSS of 1.15 for a vehicle implies that the
occupants in that vehicle are 15 percent more likely to sustain
serious injury than a vehicle representing the baseline risk.
Frontal Crash Test Rating
The historical frontal NCAP crash test data for the driver from
the model years 1995 through 2008 were examined using the injury
risk curves presented in Appendix C.
The average risk of injury to the head, neck, chest, and femur
of the driver, computed using the injury risk curves from Appendix
C, for each vehicle of model years 2004 to 2008 is presented in
Figure 1.
[[Page 40046]]
[GRAPHIC] [TIFF OMITTED] TN11JY08.005
When compared to data from 1995, these data indicate that the
average risk of injury to the driver by model year has been reduced
since 1995 and is less than 0.2 after MY 2002 (Table 2). If the
average performance of all the vehicles tested in NCAP each year is
used to represent the fleet of new cars, then for MY 2008, the
average risk of serious injury in the fleet is approximately 0.15.
Therefore, the baseline injury risk of 0.15 was used to compute the
relative risk of injury in frontal crashes for each vehicle (Table
3).
Table 1.--Probability of Injury Statistics for Drivers in NCAP Frontal Crash Tests by Model Year
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average Prob Std. P 25% P 75%
MY prob deviation Minimum P quartile P Median quartile Maximum P
--------------------------------------------------------------------------------------------------------------------------------------------------------
1995......................................................... 0.30 0.12 0.10 0.21 0.27 0.35 0.62
1996......................................................... 0.32 0.18 0.13 0.18 0.28 0.40 0.86
1997......................................................... 0.26 0.14 0.12 0.17 0.22 0.28 0.69
1998......................................................... 0.26 0.11 0.11 0.20 0.24 0.30 0.63
1999......................................................... 0.29 0.18 0.09 0.17 0.23 0.36 0.71
2000......................................................... 0.25 0.15 0.11 0.15 0.22 0.28 0.64
2001......................................................... 0.23 0.12 0.09 0.17 0.19 0.26 0.63
2002......................................................... 0.20 0.09 0.09 0.14 0.17 0.22 0.61
2003......................................................... 0.18 0.09 0.08 0.12 0.15 0.18 0.45
2004......................................................... 0.15 0.07 0.08 0.11 0.14 0.18 0.46
2005......................................................... 0.17 0.11 0.09 0.11 0.14 0.19 0.57
2006......................................................... 0.17 0.06 0.08 0.13 0.15 0.22 0.31
2007......................................................... 0.15 0.05 0.09 0.12 0.14 0.17 0.38
2008......................................................... 0.15 0.04 0.09 0.12 0.14 0.18 0.24
Average MY 1995-2008 0.10 0.15 0.19 0.25 0.56
Average MY 2004-2008 0.08 0.12 0.14 0.19 0.39
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The average, minimum, maximum, and the quartiles presented in
Table 3 provide an estimate of the dispersion of Relative Risk Score
(RRS) in different model years. Since most of the current vehicles
receive four or five stars in the NCAP frontal crash tests, NHTSA
prescribed the baseline risk of 15 percent (representing the average
risk of injury to the driver in MY 2007 and MY 2008 vehicles in the
NCAP frontal crash test) to be at the border of the 4 star and 3
star rating. Other criteria used to determine the star bands were
(1) vehicles performing exceptionally well (at 0-15 percentile of
vehicles tested) are assigned a five star rating, and (2) vehicles
performing very poorly (greater than 4 standard deviations from
mean) would be assigned a one star. Attempts were also made to
maintain equidistant star band boundaries. Based on these criteria
and the distribution of relative risk of injury scores presented in
Table 3, the relationship between RRS and the number of stars was
established as presented in Table 4. The RRS is computed by (1)
rounding the injury risk to the nearest tenth of a percent in
accordance with the rounding-off method of ASTM Standard Practice E
29 for Using Significant Digits in Test Data to Determine
Conformance with Specifications, (2) dividing the injury risk by
0.15 (15.0 percent baseline injury risk), (3) and finally rounding
the result to the nearest one hundredth in accordance to ASTM
Standard E 29. It should be noted that a vehicle which passes
compliance (with a 20 percent compliance margin) would have an
injury risk of 52.1 percent corresponding to a RRS value of 3.47.
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[[Page 40049]]
Side Crash Test Rating
Because the agency did not have test data using the ES 2re or
SID IIs dummies at the NCAP test speed for the MDB test, the agency
computed the average risk of serious injury derived from relevant
MDB tests and oblique pole impact tests done in support of the FMVSS
214 side impact protection upgrade. The MDB test is conducted with
the ES-2re dummy in the front driver seat and the SID-IIs in the
rear passenger seat. The pole impact test is conduced with the SID-
IIs in the driver's seat.
The injury risk curves for side impact reported in Appendix C
are applied to side MDB tests and oblique pole tests. These tests
were part of NHTSA's fleet evaluation for the FMVSS 214 side impact
upgrade and details and thorough analysis of these tests are
available in the NHTSA docket number NHTSA-2007-25441.
There were six vehicles which were tested in the FMVSS 214 test
conditions (MDB impact at 53 km/h rather than the NCAP 62 km/h) as
well as the oblique pole impact with the SID-IIs dummies. The dummy
injury measures in the paired crash tests of these vehicles with the
ES-2re and SID-IIs dummies were used to determine risk of injury in
side crashes and a Relative Risk Score (RRS) for side crashes. Table
4 presents the statistics for the risk of injury (average, standard
deviation, minimum, maximum, median, and 25 and 75 percentile injury
risk values) for each dummy in the MDB and oblique pole tests using
the injury risk curves from Appendix C.
The overall risk of injury to the driver for each vehicle is the
weighted average of the driver injury risk in the MDB test
(multiplied by 0.8) and that in the oblique pole test (multiplied by
0.2). The risk of injuries in side crashes for a vehicle is the
simple average of the injury risk of the rear seat passenger in the
MDB test and the overall driver injury risk. Table 4 also presents
the statistics for the overall risk of injury to the driver and the
risk of injury in side crashes.
Table 4.--Probability of Injury (P) Statistics for Different Occupants in the Side MDB and the Oblique Pole Crash Tests
--------------------------------------------------------------------------------------------------------------------------------------------------------
25% 75%
Crash type Average P Std. Dev. P Min P quartile P Median P quartile P Max P
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MDB Driver................................................... 0.09 0.04 0.04 0.06 0.09 0.12 0.13
MDB Pass..................................................... 0.13 0.21 0.03 0.03 0.04 0.07 0.55
Pole Driver.................................................. 0.64 0.39 0.13 0.32 0.79 0.93 0.98
Overall Driver............................................... 0.20 0.11 0.06 0.12 0.23 0.28 0.30
Side Impact.................................................. 0.16 0.16 0.05 0.07 0.14 0.18 0.43
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The overall risk of injury to the driver is computed as the weighted average of the risk of driver injury in the MDB test (multiplied by 0.8)
and the risk of driver injury in the pole test (multiplied by 0.2).
The risk of injury in side impact is the average of the overall driver risk and the risk of rear passenger in the MDB test.
The average risk of injury from the six MDB tests for the driver
and the rear passenger is 0.09 and 0.13, respectively. The average
risk of injury to the driver in the six oblique pole tests is 0.64
and the average overall risk of injury to the driver (combining the
MDB and pole test results) is 0.20. For these six vehicles, the
average risk of injury in side crashes is 0.16.
In order to promote improvement in side impact safety in all the
vehicles, the baseline risk of injury to compute Relative Risk
Scores (RRS) in side crashes is taken to be 15 percent. As in
frontal crash tests, the RRS in side MDB and pole crash tests is
computed by 1) rounding the injury risk to the nearest tenth of a
percent in accordance with the rounding-off method of ASTM Standard
Practice E 29 for Using Significant Digits in Test Data to Determine
Conformance with Specifications, 2) dividing the injury risk by 0.15
(15.0 percent baseline injury risk), 3) and finally rounding the
result to the nearest one hundredth in accordance to ASTM Standard E
29. Table 5 presents the RRS statistics corresponding to the injury
risk presented in Table 4 using a baseline injury risk of 15
percent.
Table 5.--Relative Risk Score (RRS) Statistics for Different Occupants in the Side MDB and the Oblique Pole Crash Tests
--------------------------------------------------------------------------------------------------------------------------------------------------------
25% 75%
Crash type Average RRS Std. Dev. Min RRS quartile Median RRS quartile Max RRS
RRS RRS RRS
--------------------------------------------------------------------------------------------------------------------------------------------------------
MDB Driver................................................... 0.60 0.25 0.28 0.42 0.59 0.80 0.87
MDB Pass..................................................... 0.86 1.39 0.20 0.21 0.28 0.45 3.69
Pole Driver.................................................. 4.27 2.57 0.89 2.15 5.24 6.23 6.54
Overall Driver............................................... 1.33 0.71 0.40 0.77 1.52 1.89 2.00
Side Impact.................................................. 1.09 1.05 0.30 0.49 0.90 1.17 2.84
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The Relative Risk Score for MDB tests, pole tests, and side impacts is obtained by dividing the risk of injury in each side crash mode listed
in Table 4 by 0.15 which represents the baseline risk of injury in side impacts.
Vehicles for which all the dummy injury measures (for the ES-2re
and SID-IIs) in the MDB and pole tests just meet the compliance
limits, the risk of injury is 0.70 for the ES-2re and 0.42 for the
SID IIs dummies resulting in an overall risk of injury in side
crashes of 0.532, a RRS of 3.54.
Rollover Rating
Since the proposed rollover rating is the same as that currently
used in NCAP, the current relationship between the risk of rollover
and star rating used in NCAP is applied here and is shown in Table
11. If 15 percent risk (corresponding to a 4 star rating) is used as
the baseline risk (as that in front and side crash test rating),
then the relationship between the vehicle safety score in rollover
is as shown in Table 11.
[[Page 40050]]
Table 11.--Star Rating, Risk of Rollover, and the Relative Risk score in Rollover
[Using a baseline risk of 15 percent]
----------------------------------------------------------------------------------------------------------------
Number of stars Risk of rollover Relative risk score in rollover
----------------------------------------------------------------------------------------------------------------
1 star.................................. P >= 40 percent............ RRS >= 2.67
2 stars................................. 30 <= P < 40 percent....... 2.0 <= RRS < 2.67
3 stars................................. 20 <= P < 30 percent....... 1.33 <= RRS < 2.0
4 stars................................. 10 <= P < 20 percent....... 0.67 <= RRS < 1.33
5 stars................................. P < 10 percent............. RRS < 0.67
----------------------------------------------------------------------------------------------------------------
Combined Crashworthiness Rating Vehicle Safety Score
The weighted average of the Relative Risk Scores (RRS) in front,
side, and rollover crashes is the combined crashworthiness rating
Vehicle Safety Score (VSS). The weight applied to each crash mode
represents the proportion of injury associated with that crash mode.
Since the baseline injury risk used to compute RRS in each crash
mode is 15 percent, the combined crashworthiness rating also
represents the relative risk of injury with respect to a baseline of
15 percent. The Vehicle Safety Score for the Combined
Crashworthiness Rating is computed below:
Combined Rating = (5/12) x RRS(front) + (4/12) x RRS(side) + (3/12)
x RRS(roll)
The final VSS value is obtained by rounding the result from the
above equation to the nearest one hundredth in accordance to ASTM
Standard E 29. The star bands used for rating frontal and side
impacts are applied to the combined crashworthiness rating using VSS
and is presented in Table 12.
Table 12.--Relationship Between Vehicle Safety Score and the Star Rating
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5 stars 4 stars 3 stars 2 stars 1 star
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VSS Values................... VSS <0.67.............. 0.67 <= VSS <1.00...... 1.00 <= VSS < 1.33..... 1.33 <= VSS < 2.67.... VSS >= 2.67
Probability.................. P < 0.100.............. 0.100 <= P < 0.150..... 0.150 <= P < 0.200..... 0.200 <= P < 0.400.... P >= 0.400
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Authority: 49 U.S.C. Sec. Sec. 32302, 30111, 30115, 30117,
30166, and 30168, and Pub. L. 106-414, 114 Stat. 1800; delegation of
authority at 49 CFR 1.50.
Issued on: July 3, 2008.
Nicole R. Nason,
Administrator.
[FR Doc. E8-15620 Filed 7-10-08; 8:45 am]
BILLING CODE 4910-59-P