05-21465. Federal Motor Vehicle Safety Standards

AGENCY:

National Highway Traffic Safety Administration (NHTSA), DOT.

ACTION:

Denial of petition for rulemaking.

SUMMARY:

This document denies a petition for rulemaking submitted by Honda Motor Co., Ltd. (Honda), to amend Federal Motor Vehicle Safety Standard (FMVSS) No. 213, “Child restraint systems.” Honda requested that FMVSS No. 213 be amended to limit the weight of all child restraint systems used with the 3-year-old dummy. Honda stated that such an amendment would assure the proper operation of weight-based occupant detection systems used to meet the air bag suppression requirements of FMVSS No. 208, “Occupant crash protection.”

FOR FURTHER INFORMATION CONTACT:

For Non-Legal Issues: Mr. Tewabe Asebe, Office of Crashworthiness Standards, National Highway Traffic Safety Administration, 400 Seventh Street, SW., Washington, DC 20590, Telephone: [phone].

For Legal Issues: Mr. Chris Calamita, Office of Chief Counsel, National Highway Traffic Safety Administration, 400 Seventh Street, SW., Washington, DC 20590, Telephone: [phone], Facsimile: [phone].

SUPPLEMENTARY INFORMATION:

I. Background

On May 12, 2000, NHTSA issued a final rule for advanced air bags, amending FMVSS No. 208 to, among other things, minimize injuries to small adults and young children due to air bag deployment (65 FR 30680). To address the risk air bags pose to young children in child restraint systems, the agency amended FMVSS No. 208 to include a number of alternative tests, one of which requires the front passenger air bag system to automatically suppress when a child or child in a child restraint system is present. Some manufacturers rely on weight-based technology to comply with the automatic air bag suppression requirement. Weight-based technologies utilize load cells or other sensors designed into the vehicle seat. With this option, the vehicle air bag in the right front passenger seat is suppressed when a child or a child in a child restraint system is placed on the seat. If an adult occupies the front passenger seat, the feature enables the air bag deployment. The threshold for enabling the air bag deployment is dependent on the design and calibration of the suppression system used.

The agency selected certain child restraint systems to be used for compliance testing of the air bag suppression systems. The selected child restraint systems are included as an appendix (Appendix A, “Selection of child restraint systems”) in FMVSS No. 208. The list of child restraint systems is periodically updated to reflect child restraint systems currently on the market. On November 19, 2003, the agency updated the list of child restraint systems in Appendix A of FMVSS No. 208 (68 FR 65179). FMVSS No. 208 requires that vehicles be certified for compliance using any of the child restraint systems in Appendix A.

II. The Petition

On February 11, 2004, the agency received a petition for rulemaking from Honda requesting that NHTSA amend FMVSS No. 213 to limit the weight of all child restraint systems, including rear-facing, forward-facing, and convertible type restraints used by 3-year-old children and produced in accordance with FMVSS No. 213, for the purpose of maintaining the appropriate air bag deployment for small occupants. Honda suggested that, based on available child restraint system designs, “perhaps a weight limit of about 8.5 kilograms (kg) (18.7 lb) may be appropriate.”

As Honda's petition specifically addresses the air bag suppression requirements for child restraints used with the 3-year-old dummy, NHTSA notes that manufacturers choosing to certify to FMVSS No. 208 S21.2, Option-Automatic suppression feature, must demonstrate compliance when using any of the child restraints listed in sections C and D of FMVSS No. 208 Appendix A. These child restraints include (1) forward-facing toddler and forward-facing convertible seats, and (2) forward-facing toddler/belt positioning-booster seats and belt-positioning booster seats.

In its petition, Honda stated that it agrees with NHTSA that it is very important to periodically update the child restraint system list in Appendix A of FMVSS No. 208. However, Honda claimed that the weight of certain child restraint system models recommended for 3-year-old children in the updated list were heavier than others. Honda proposed to limit the child restraint system mass to about 8.5 kg (18.7 pounds). Specifically, the petitioner stated:

A current, popular system for automatic suppression of the air bag for the infant and small child is seat weight detection. If increasingly heavier CRSs are added to the market endlessly, the stable and reliable performance of small occupant detection systems cannot be achieved. Consequently, future air bag suppression systems designed to prevent deployment with infants or small children in very heavy future CRSs could also suppress deployment for small adults such as the AF5 (5th percentile adult female). We are also concerned that older vehicles already on the road with suppression systems calibrated to the lower weights of older CRS specifications will fail to recognize newer, heavier designs. This means the air bag could deploy for an infant or small child in a very heavy CRS in vehicles calibrated to lighter weight CRSs that were on the market at the time the vehicle suppression system was designed.

Therefore, we believe NHTSA should amend the FMVSS No. 213, “Child Restraint Systems,” to limit the weight of all C3Y (Three-year-old Child Dummy) CRSs (including rear-facing, forward-facing and convertible type CRSs) produced in accordance with FMVSS 213 for the purpose of maintaining the appropriate airbag deployment for small occupants. Based on the CRS designs available, perhaps a weight limit of about 8.5 kilograms may be appropriate.

Based on the wide variety of CRS designs already on the market, Honda does not believe this simple requirement would unduly limit CRS designs or performance. A lighter CRS weight would assist in assuring the proper operation of weight-based air bag suppression systems and would add to consumer convenience and usage by being easier to carry and install in a vehicle.

III. Data

Honda provided the mass distribution for the child restraint systems in Appendix A of FMVSS No. 208. The weight distribution for these restraints ranged from about 1.5 kg (3.3 pounds) for Evenflo Right Fit to about 7.9 kg (17.4 pounds) for Britax Expressway ISOFIX, with an average weight of about 4.6 kg (11 pounds). Honda proposed to limit the child restraint system weight to about 8.5 kg (18.7 pounds). It is important to note that as currently written, FMVSS No. 213 is a performance standard, and as such, does not specify any weight limit on particular child restraint system designs.

While Honda's petition provided the weight of the child restraint systems currently included in Appendix A of FMVSS No. 208, NHTSA obtained the weight of a number of varying restraint designs, either currently available or available in recent years, including infant beds, infant seats with and without a base, convertible child seats, forward-facing only seats, combination child and booster seats, and booster seats child restraints.^[1] From this list, NHTSA examined the weights of those restraints that could possibly be included in sections C and D of FMVSS No. 208 Appendix A, and therefore relevant to the subject petition (e.g., forward-facing toddler, forward-facing convertible seats, forward-facing toddler/belt positioning-booster seats, and belt-positioning booster seats). While the vast majority of these child restraint systems weigh less than the Britax Expressway ISOFIX (currently, the heaviest child restraint system included in Appendix A of FMVSS No. 208), NHTSA found at least seven child restraint systems heavier than the Britax Expressway ISOFIX. Further, six of these are heavier than the 8.5 kg limit suggested by Honda in its petition.

IV. Analysis

Appendix A of FMVSS No. 208 specifies a list of child restraint systems that may be used by NHTSA to test the air bag suppression systems of a vehicle that has been certified as complying with S19, S21, or S23 of FMVSS No. 208. When selecting a child restraint system to be included in Appendix A, the agency considers a number of different factors. These factors are outlined in the agency's November 2003, final rule as follows:

In deciding whether to amend Appendix A, NHTSA will consider a number of factors, such as whether a particular restraint has been a high volume model, whether it has mass and dimensions that are representative of many restraints on the market, whether its mass and dimensions represent outliers, and whether a variety of restraint manufacturers are represented in the appendix. This approach will allow us to limit Appendix A to those restraints that represent large portions of the CRS market, while including exceptionally large or small restraints. We believe a combination of restraints is needed to assure the robustness of automatic suppression systems under real world conditions.

Specifically with respect to Honda's concern about the increasing weight of child restraint systems, the heaviest child restraint system selected for inclusion in Appendix A, as amended in the November 19, 2003 final rule, is about 0.5 kg (1.1 lbs) heavier than the heaviest child restraint system removed from Appendix A. However, as noted earlier, the Britax Expressway ISOFIX is lighter than at least seven other child restraint systems either currently available or available in recent years that could be included in sections C and D of FMVSS No. 208 Appendix A. Importantly, NHTSA notes that there is no single established weight threshold for all weight-based air bag suppression systems on the market. The design of these systems may vary depending on a number of different parameters, as long as the system adequately suppresses the air bag when tested in accordance with the requirements of FMVSS No. 208.

Honda stated that for weight-based occupant detection systems used for air bag suppression, if increasingly heavier child restraint systems are added to the market endlessly, the stable and reliable performance of small occupant detection systems could not be achieved. NHTSA does not believe that the addition of the Britax Expressway ISOFIX, the heaviest child restraint system included in Appendix A of FMVSS No. 208 to date, serves as an indication that child restraints are becoming heavier. As noted earlier, NHTSA has identified at least nine child restraint systems that are above the 8.5 kg mass limit proposed by Honda. However, as FMVSS No. 213 does not require child restraint systems to meet specific weight limits, NHTSA does not weigh the restraints as part of its annual compliance test program. As such, the agency has no historical data to show that there is a trend towards increasingly heavier child restraint systems as implied by Honda. Further, Honda did not provide such data in support of its petition.

The agency did estimate that, in order to comply with the requirement that all child restraint systems have hardware enabling the restraint to attach to the universal child restraint anchorage system required in vehicles as a result of FMVSS No. 225, “Child restraint anchorage systems,” each child restraint system would have an incremental weight increase ranging from less than 0.45 kg (1 pound) to 1.36 kg (3 pounds) depending on the type of attachment hardware used.^[2] To date, virtually all child restraint systems have adopted the use of flexible-type attachment hardware, which only marginally increases the weight of the child restraint system. Notably, the heaviest child restraint system in Appendix A of FMVSS No. 208-the Britax Expressway ISOFIX-is a restraint that utilizes a rigid lower attachment system to connect to the vehicle anchorages and is designed for forward-facing use. These rigid anchorages are typically heavier than the flexible attachment hardware that is predominant in current designs. However, we note that the Britax Expressway ISOFIX, at 7.9 kg (17.4 lb), is still significantly lighter than the heaviest child restraint system examined by NHTSA-the Britax Super Elite (a forward-facing seat for children weighing between 22 and 80 pounds, equipped with a 5-point harness restraint system) at 11.6 kg (25.6 lb).

Honda stated that based on the wide variety of child restraint system designs already on the market, the company does not believe a weight limit requirement would unduly limit child restraint system design or performance. However, Honda did not present evidence to support this claim. Absent such evidence, there is no way for the agency to confirm Honda's assertion. As noted earlier, FMVSS No. 213-as with the other FMVSSs-is a performance standard. The agency does not believe that it is appropriate to impose design-restrictive requirements that may hinder the development of safety features for use in future child restraint system designs. For example, NHTSA is conducting ongoing research in the area of improved side impact protection for children in crashes in response to the Transportation Recall, Enhancement, Accountability and Documentation (TREAD) Act. NHTSA does not want to put constraints on potential innovative designs that could improve safety for children in this or other areas in the future, and believes that imposing design-restrictive parameters for child restraints-such as imposing a weight limit as suggested in the subject petition-could potentially preclude the development of safety advances. While FMVSS No. 213 does not currently specify weight limits on child restraint designs, the agency notes, as did Honda, that lighter weight child restraint systems can be considered more user-friendly in that they are easier to move from one vehicle to another and from one seating position to another in the same vehicle if needed.

Honda stated that it is concerned that older vehicles that are already on the road, with suppression systems calibrated to the lower weights of older child restraint systems, will fail to recognize newer and heavier child restraint systems. Honda stated that the air bag could deploy for an infant or small child in a very heavy child restraint system in vehicles calibrated to lighter weight child restraint systems that were on the market at the time the vehicle suppression system was designed. NHTSA notes that the mass of the Britax Expressway ISOFIX is only 0.5 kg (1.1 lb) more than the previous heaviest child restraint system included in Appendix A. This is a very nominal increase (approximately 3 percent) in child restraint mass, and the agency would expect that the margin of safety designed into the occupant detection systems used to control air bag suppression systems is sufficient to address such small changes in child restraint system mass. This is especially important given that the agency has identified a number of child restraints either currently available or available in the recent past that are heavier- and in some cases, significantly heavier-than the Britax Expressway ISOFIX.

While Honda proposed to limit child restraint system design mass to about 8.5 kg (18.7 lb), it did not provide any rationale or supporting data to justify this 8.5 kg limit. This, coupled with the fact that there is no single established weight threshold for all weight-based air bag suppression systems on the market, does not support the adoption of Honda's proposed amendment. The agency does not have a rationale to restrict the mass of child restraint systems to a limit of 8.5 kg at this time.

While NHTSA does not believe that amendments are necessary at this time, the agency shares Honda's concern. As noted earlier, the agency does not weigh child restraints as part of the FMVSS No. 213 compliance test program. However, the agency does now weigh these seats for use in (1) developing future upgrades to Appendix A of FMVSS No. 208 and (2) the agency's Child Restraint Ease of Use Ratings Program. In addition, we will continue to monitor developments on this matter through the Society of Automotive Engineers-Child Restraint Systems Standard Committee, whose members include motor vehicle and motor vehicle equipment manufacturers, and child restraint systems manufacturers. This committee has been and continues to be in dialog on this subject, and we will ensure that the concerns are well communicated.

VI. Conclusion

The agency has clearly noted the composition of Appendix A is intended to represent large portions of the child restraint system market, while including exceptionally large or small restraints. This combination of restraints is needed to assure the robustness of automatic suppression systems under real world conditions. It is also important to note that when Appendix A was amended in November 2003, the Britax Expressway ISOFIX was unique in design, in that it was the only child restraint system available with rigid Lower Anchors and Tethers for Children (LATCH) attachments. While the agency has identified a small percentage of child restraint systems that weigh more than the Britax Expressway ISOFIX, the inclusion of heavier child restraint system designs is not inconsistent with the intent of Appendix A of FMVSS No. 208. Further, while the Britax Expressway ISOFIX is approximately 0.5 kg (1.1 lb) heavier than the heaviest child restraint system that was removed from Appendix A as amended in the November 2003 final rule, the agency does not consider this to be an indication that child restraint system designs are increasing in weight.

As noted earlier, FMVSS No. 213 is a performance standard, and does not specify particular design constraints such as mass and/or dimensions. Honda did not provide any rationale for its proposal to limit child restraint system designs to a maximum of 8.5 kg (18.7 lb). NHTSA has not identified any real-world data to support the need to limit the weight of child restraint systems, and specifically as it relates to the performance of occupant detection systems for automatic air bag suppression. Further, specification of a child restraint system mass limit, when considered in conjunction with the mass of the dummy used in air bag suppression testing, would effectively establish a weight threshold for weight-based air bag suppression systems. It is not the intent of the agency to specify such a threshold. Each vehicle manufacturer is responsible for meeting the requirements of FMVSS No. 208 when using any of the child restraint systems listed in Appendix A.

In consideration of the foregoing, NHTSA is denying Honda's petition for rulemaking to amend FMVSS No. 213 to adopt a design weight limit for child restraint systems used with the 3-year-old dummy. In accordance with 49 CFR Part 552, this completes the agency's review of the petition.

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

Issued on: October 13, 2005.

Stephen R. Kratzke,

Associate Administrator for Rulemaking.

Footnotes

1.  SafetyBeltSafe U.S.A. provided the weights of these varying child restraints to NHTSA. A list of the restrint make/models and weights has been submitted separately to this docket.

2.  Final Economic Assessment, FMVSS No. 213, FMVSS No. 225, Child Restraint Systems, Child Restraint Anchorage Systems. Docket No. NHTSA-1998-3390-27, Page 44, February 1999.