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U.S. Department of Transportation
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RE: Docket No. NHTSA-2001-10053-Notice 1

Comments Submission
of
CONSUMERS UNION OF UNITED STATES, Inc.
to
National Highway Traffic Safety Administration
on
Safety Rating Program for Child Restraint Systems

Introduction

Consumers Union (CU), publisher of Consumer Reports, welcomes the opportunity to comment on the proposed Safety Rating Program for Child Restraint Systems (CRS).

Consumers Union has long supported NHTSA's efforts to develop a rating system for child restraints. In February 1999, at a public meeting (65 FR 1224, January 7, 2000 Docket No. NHTSA-2000-6628) sponsored by NHTSA in Washington D.C. to discuss the safety performance of child restraint systems and options for giving the public information on the performance of different child restraints, CU described its CRS rating process. At that time CU noted that while we were the only organization currently rating child restraints, we supported NHTSA putting its resources behind a government testing and rating system because that would likely increase the number of seats tested and thereby provide consumers with increased information on child restraints and enhance their purchasing options.

CU has petitioned NHTSA in years past when our testing indicated that specific child restraints did not meet the safety standards set by the agency, or whose claims for safety did not stand up to actual testing. In 1995, three child restraints failed CU's crash tests, which were conducted under testing protocols very similar to those set out by NHTSA. CU was concerned that these child restraints, which were on the market at the time, would not deliver the level of safety to children promised by the manufacturers. In our petition we asked for a recall of those seats.(1) We also asked that NHTSA cease the practice of permitting manufacturers to label a seat as safe for use up to a maximum child weight, while not requiring the manufacturer to test the seat with a dummy at that weight. Our concern was underscored, once again, by our testing, which indicated that certain seats failed when the dummy's weight was at the highest end of the advertised weight limit for that seat.

We remain concerned with NHTSA's practice of allowing CRS manufacturers to label a seat as safe for a child at, say 22 pounds, while permitting the seat to be tested with a dummy at only 20 pounds. There needs to be some objective, dependable assurance that child restraints will provide adequate safety when occupied by a child at the weight listed by the manufacturer as the maximum safe occupant weight. Two additional pounds can significantly increase the kinetic energy of the child in a crash, and as our 1995 testing demonstrated, can mean the difference between adequate protection and certain danger to that child. Indeed, consumers have a right to expect that their federal highway safety agency will require "truth in advertising" from manufacturers, and we urge NHTSA to correct this discrepancy during this rulemaking, when it is revising the testing protocols and rules for car seats.

Comments on NHTSA's Notice for Comment

Combined Child Restraint Rating, Section VI.

Consumers Union believes that a single summary rating, which combines Ease of Use and Dynamic Crash Performance results (while also allowing consumers to see the individual ratings for Ease of Use and Dynamic Crash Performance), is most helpful to consumers looking for guidance in purchasing a CRS. Please see our recommendations for arriving at single summary ratings, which are appended to these comments. As recently shown (see NHTSA's Figure 6 and 7), compliance tests and higher speed sled tests with scaled Injury Probability Curves for NCAP result in nearly all seats receiving a 5-star rating. The only factor that distinguishes these seats from one another-a factor that is essential to the ultimate safe use of the product-is their ease of use and their fit inside the vehicle.

CU found in its own recent CRS sled crash testing that when we introduced from one to three inches of slack into the CRS harness, the HIC (head injury criteria) and chest g values increased significantly. (See July 2001 Consumer Reports, "Traveling With Children.") Dynamic crash performance is primarily a safety parameter, but ease-of-use, as our testing showed, is safety-related as well. If parents and caregivers have to struggle to tighten a harness or simply cannot do so adequately, the result is a harness with excessive slack that poses a serious safety problem for the child in a crash. Similarly, secure fit to the vehicle is important. It is therefore of the utmost importance that a CRS harness fit snugly and be easy to adjust, and that the CRS be easy and simple to secure to the vehicle.

In the area of performance standards in dynamic tests of CRS, CU notes that Occupant Crash Protection for airbag loading (under FMVSS 208, the airbag standard) has more stringent requirements than does Standard No. 213, the CRS standard. This makes no sense from a safety standpoint. CU believes that NHTSA should address this discrepancy by requiring that the acceptance criteria in FMVSS 208, which call for a HIC of no more than 390 (15 ms window) and a clipped Chest G <=50 value for the 12-month dummy, and 570 for the three-year dummy (15 ms window) and Chest G < = 55 be included in FMVSS 213.

CRS Ease of Use Rating Section IV.

Because of their high degree of repeatability, we agree with NHTSA's proposal to rate four major components comprising Ease of Use: Assembly, Evaluation of Labels/Instructions, Securing the Child, and Installation in Vehicle. As our experience at Consumers Union has shown over the years, it is very important to rate such performance against clearly defined standards. CU's test engineers, using well-defined and agreed-to criteria, rate consumer products such as child restraints objectively, and achieve a high degree of repeatability and reproducibility.

It is important that the features being rated adequately and completely represent "Ease of Use" of child restraints. As a result, we highly recommend the addition of the following features to the evaluation program:

CU supports use of a "generic minivan bench" in the Ease of Use evaluations and suggests that the bench be equipped with a 3-point belt in at least one seat position, as 3-point belts can, in some cases, present more difficult installation issues than lap belts. We do, however, suggest that additional "Fit to the Vehicle" assessments be made on the basis of fit to particularly hard-to-fit vehicles (small vehicles with contoured seats, low head room, narrowly spaced seat belt anchors, etc.).

Because Consumers Union feels that a rating of a multi-use product should not exclude a major mode of use, CU also urges including an evaluation of Ease of Use of a convertible CRS in its rear-facing application in addition to its front-facing application.

Weighting the Features to arrive at Ease of Use Rating

CU agrees with NHTSA that a seat should not receive an A rating if more than one out of four categories is rated below an A. Likewise, a seat should not receive a B rating if more than one of four categories is a C. We recommend that this "limiting factor" approach be applied to the individual Ease of Use categories, as well.

For example, for the Labels and Instructions portion of the rating featured in NHTSA's Appendix C, it is possible that if this seat's labels were found durable enough to attain an A rating that this seat could receive an overall Labels and Instructions score of 48 points, enough to achieve an A rating, while at the same time receiving C ratings in the two most critical (3 weight) features. Simply put, if a seat receives the lowest C rating score for any feature in a given category, this should prevent the seat from receiving an overall A score for that category.

Dynamic Testing and NCAP Testing

CU does not favor the use of NCAP vehicle crash testing for rating child restraints. Such testing adds a new and complicated variable--child restraint and vehicle interaction--while at the same time limiting the seat and vehicle combinations that can be tested in a timely manner. The increased costs would likely be prohibitively expensive, and the resultant delays would deny consumers any information on major segments of the CRS market. Rather, dynamic tests used in CRS ratings should be evaluated in a sled test program to provide information on the child seat separate from the vehicle. Such an approach will result in far more seats being evaluated in a timely and cost-efficient manner.

Once again, because Consumers Union believes that an adequate rating of a multi-use product should not exclude rating a major mode of use, CU also suggests including Dynamic Performance of a convertible CRS in its rear-facing mode in addition to its front-facing orientation. For this purpose, we suggest inclusion of the following ratings criteria--back angles--to Dynamic Performance and to a combined overall Rating.

Table 1

BACK ANGLE RATING
Greater than 70°	= Failure
65 to 70 °	= 1 star
60 to 65°	= 2 star
55 to 60 °	= 3 star
50 to 55 °	= 4 star
45 to 50 °	= 5 star

CU urges that in the future as the Rating program matures, all CRSs, including rear-facing infant seats, be rated.

While not practical for rating child restraint systems, NCAP vehicle crash testing with child restraints installed does offer the opportunity for a "free ride" in looking at crash forces and compatibility issues related to children in vehicles. Valuable research information can be obtained by including child restraints in both front and side vehicle crash tests to evaluate forces exerted on restrained children. NCAP vehicle crash testing may also be useful in evaluating the compatibility issues, such as belts anchored forward of seat bights, large locking belt tangs, and the relationship between contoured/bucket seats and injury and excursion criteria. CU believes that NHTSA should pay particular attention to the forces on child dummies in side-impact tests, where much controversy and question remains.

Dynamic Sled Testing Speed

CU supports the use of a higher speed sled test for evaluating the performance of child restraints in dynamic testing. We support NHTSA's proposal to test CRSs at 35 mph for the purpose of the CRS rating system.

NHTSA's Request for Comment indicates that, "Forward facing child restraints would be placed on the same seat used for the compliance test. The restraint would be secured using the LATCH system." This is cause for some confusion and concern. While the LATCH system is meant to eliminate many ease-of-use and compatibility issues, it currently doesn't represent the majority of cars on the road and represents even fewer child seats. Certainly the vehicle seat used for both compliance and sled tests should be modified to include LATCH, but all seats should be tested for Dynamic Performance using both LATCH and belt routing for the next several years.

Finally, as stated earlier, CU supports replacing the current 1975 Impala type bench seat used for compliance testing, and sled testing with a sled seat that reflects more current materials, belt styling and seat contour. As suggested by vehicle manufacturers such as Ford, it may be important to hold the dynamic portion of the CRS ratings until such a time as changes to FMVSS 213 are complete, as our assumption is that proposed FMVSS 213 changes will include some update of the sled test vehicle seat. Ease of Use ratings could begin prior to FMVSS 213 updates, however, as the Dynamic Performance and Ease of Use ratings are intended to be presented separately, as well as possibly in a combined overall Rating (see appendix).

We appreciate the opportunity to present our views on increasing the safety of this important consumer product. If we can answer specific questions regarding our comments, please contact Sally Greenberg in our Washington office.

January 9, 2002	Respectfully submitted,
	CONSUMERS UNION 1666 Connecticut Avenue, NW Washington, DC 20015 202-462-6262
R. David Pittle Senior Vice President, Technical Policy	Sally Greenberg Senior Product Safety Counsel
Werner Freitag Project Director, Recreation and Home Improvement	Michael Saccucci Director of Statistical Services
Eugene Peterson Senior Automotive and Tire Test Engineer	Jennifer Stockburger Automotive and Tire Test Engineer

 

 

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APPENDIX

Summary of Proposed Overall Rating System

Consumers Union believes that an overall summary rating combining Ease of Use and Dynamic Performance should be developed and provided together with the individual Ease of Use and Dynamic Performance ratings. An overall rating enables a consumer to consider models in a manner consistent with overall performance, instead of alphabetically. More importantly, because the overall safety of a child restraint depends on both its Dynamic Performance and the way in which it can be used, an overall rating should take both of these attributes into account.

We further believe that the most useful way to combine the Ease of Use and the Dynamic Performance ratings is to first convert the individual ratings to a continuous scale since this enables the consumer to more closely differentiate between the various models and minimizes round off problems. However, such a system may be too complicated for NHTSA's program, and an alternative method, one that is consistent with the '5-star' rating system for Dynamic Performance and the 'ABC' rating system for Ease of Use, is summarized below in Table 2.

Since the overall safety of a child restraint depends in large part on the way it is used, we believe the Ease of Use rating should be treated as a "limiting factor" in a manner similar to the criteria proposed by NHTSA for calculating the individual Ease of Use category ratings. In our opinion, a seat that is so difficult to use properly as to warrant a C rating could not earn an overall rating higher than two stars-regardless of its Dynamic Performance rating in crash tests. In our view, seat design must be focused on the parent or caregiver's need to use the seat safely and efficiently. Seats that are too complicated or unfriendly to the child's parent or caregiver will likely be used improperly and thereby not provide the child the protection intended-notwithstanding its performance in crash tests. In its consideration of such a system, NHTSA can readily propose an overall rating that reflects its judgment about the role and importance of Ease of Use in child seat safety.

 

Table 2: Proposed Overall Summary Rating

Overall Summary Rating	Dynamic Performance	Ease of Use
	5	A
	5	B
	4	A
	4	B
	3	A
	5	C
	4	C
	3	B
	2	A
	3	C
	2	B
	2	C
	1	A
	1	B
	1	C