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Interpretation ID: 23663Tunick_seat_bolster_DENIED_df



    Mr. Lance Tunick
    Vehicle Services Consulting, Inc.
    P.O. Box 23078
    Santa Fe, NM 87502-3078


    Dear Mr. Tunick:

    This responds to your letter asking three questions about the pitch, roll, and yaw requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 225, "Child Restraint Anchorage Systems" (49 CFR 571.225). I apologize for the delay in responding. We have restated your questions below, followed by our answers. As discussed, we do not agree with your suggestion that the seat cushion can be removed to meet the standard's requirements.

    BACKGROUND

    Standard No. 225 requires each vehicle manufactured on or after September 1, 2002, to have a child restraint anchorage system at each of two forward-facing rear designated seating positions (see S4.4(a) and (b)). The anchorage system must meet certain configuration, strength and location requirements. S15.1.2.2 of Standard No. 225 specifies use of a "child restraint fixture (CRF)" to locate the lower bars of an anchorage system. That paragraph specifies that, with the CRF attached to the anchorages and resting on the seat cushion, the bottom surface of the CRF must have attitude angles within certain limits (with angles measured relative to the vehicle horizontal, longitudinal and transverse reference planes). (Pitch must be 15 10, roll 0 5, and yaw 0 10.) Vehicles manufactured before September 1, 2004, are permitted to meet the requirements of S15 of Standard No. 225 instead of the requirements of S9. We stated in a final rule responding to petitions for reconsideration that these pitch, roll and yaw requirements will be incorporated into the requirements of S9. 65 FR 46628.

    S9.3 of Standard No. 225 requires that each vehicle and each child restraint anchorage system in that vehicle shall be designed such that the CRF can be placed inside the vehicle and attached to the lower anchorages of each child restraint anchorage system, with adjustable seats adjusted in a specified manner.

    You state that it is difficult to fit the CRF and/or actual child restraints in the rear seats of some sports cars. You ask about the permissibility of installing a lower anchorage beneath each rear seat cushion. You state:

      The child restraint anchorage system would be used by the vehicle owner by first removing the seat bottom cushion and storing it in the vehicle's luggage compartment. The CRF, during testing, and the child seat, during real-world operation, would then be installed so as to rest stably on the metal tub (floor) of the vehicle. The location of each anchorage would be labeled as required by FMVSS 225 and the method and need of removing the seat bottom would also be labeled (the seat bottom would most probably be attached by Velcro). * * *

    DISCUSSION

      Question 1: Is the Proposed System permissible if removal of the seat bottom cushion is necessary in order for the CRF to fit in the vehicle and/or to meet pitch, roll and yaw criteria?

    We do not interpret Standard No. 225 in a manner that would permit removal of the seat cushion. S15.1.2.2(a) of Standard No. 225 specifies that the bottom surface of the CRF shall have specified attitude angles "[w]ith the CRF attached to the anchorages and resting on the seat cushion." (Emphasis added.) Under this provision, the seat cushion is not removed when measuring attitude angles.

    In addition, S9.3 of Standard No. 225 specifies that each vehicle and each child restraint anchorage system in that vehicle shall be designed such that the CRF can be placed inside the vehicle and attached to the lower anchorages of each child restraint anchorage system, with adjustable seats adjusted as described in S9.3(a) and (b). S9.3(a) and (b) state:

      (a) Place adjustable seat backs in the manufacturer's nominal design riding position in the manner specified by the manufacturer; and

      (b) Place adjustable seats in the full rearward and full downward position.

    Neither of these provisions contemplate removing the seat cushion. Accordingly, we conclude that the seat cushion is not removed when measuring pitch, roll and yaw of the CRF. If your vehicle cannot meet the requirements with the seat cushion in place, the vehicle cannot be certified as meeting Standard No. 225.

      Question 2: Is the Proposed System permissible if the CRF fits in the vehicle and meets the pitch, roll and yaw requirements with the seat bottom in place (i.e., not removed), but--

    • The child seat itself, when installed, is unacceptably unstable (e.g., as regards pitch, roll, and yaw), and

    • The lower anchorages must be located behind the middle of the seat back and thus potentially dangerous?

    Our answer to the first part of your question is that we will evaluate the vehicle's compliance with the pitch, roll and yaw requirements using the CRF with the seat bottom in place. If all child restraints are "unacceptably unstable" despite the CRF fitting the seat, then that would suggest a design problem with the rear seat, and/or a problem with the CRF, since the device is intended to be representative of a child restraint. We would appreciate learning about any situation where the standard might permit vehicle seats and anchorage systems to be designed such that child restraints can be attached in an unacceptably unstable manner. Detailed sketches would be helpful, with vehicle dimensions included.

    Our answer to the second part of this question is that an anchorage system would not be found to non-comply with the standard notwithstanding the location of the lower anchorages relative to an adult passenger's back. It should be noted, however, that you provided little information about any scenario under which the anchorages would be located "behind the middle of the seat back." With regard to passenger discomfort and safety in rear impacts, the vehicle manufacturer might want to consider using foldable or stowable anchorages, which are now permitted under Standard No. 225.

      Question 3a: If the answer to either question 1 or question 2 is "no," could the vehicle manufacturer receive an exemption under S5(e)? If an exemption is available and is obtained, could the vehicle manufacturer still install the Proposed System on a voluntary basis?

    S5(e) excludes certain rear designated seating positions from the requirement to provide a child restraint anchorage system at the position. To qualify for the exclusion, interference with transmission and/or suspension components must prevent the location of the lower bars of a child restraint changes system anywhere within the zone described by the standard such that the attitude angles could be met. Unless the situations described in your letter met those criteria, the exception would not be available. In response to the second part of your question, if the vehicle were excluded from the requirement to provide the lower anchorage bars because of impracticability, then by definition the bars would not be able to be installed, either voluntarily or to meet the provisions of the standard. Moreover, under S4.1 of Standard No. 225, each tether anchorage and child restraint anchorage system installed voluntarily or pursuant to the standard after September 1, 1999, must meet the configuration, location, marking and strength requirements of the standard.

    Before closing, we would like to address a further issue you raised. In your letter and in other correspondence with the agency, you have expressed a belief that S9.3 is invalid because, by requiring the back seat of vehicles to fit the CRF, S9.3 allegedly violates a "no design standard prohibition." Your belief is mistaken. We seek to issue Federal motor vehicle safety standards that are performance-oriented as possible, but if need be they may have the effect of imposing certain design requirements or limitations. The CRF is representative of a child restraint system. Just as we require lap and lap and shoulder seat belt assemblies to be capable of adjustment to fit occupants whose dimensions and weight range from those of a 5th-percentile adult female to those of a 95th-percentile adult male (S4.1(g) of Standard No. 209, 49 CFR 571.209), we require vehicle seats to fit the CRF to ensure better compatibility and fit between vehicle seats and child restraint systems to improve the performance of child restraints in protecting children. Further, S9.3 is performance-oriented, in that manufacturers retain flexibility in designing their vehicle seats as long as they allow placement of the CRF, and the standard does not specify dimensions or other features of the vehicle seat. Accordingly, it does not create a "design standard" that would be prohibited by statute.

    If you have further questions, please contact Deirdre Fujita of my staff at (202) 366-2992.

    Sincerely,

    Jacqueline Glassman
    Chief Counsel

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