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Interpretation ID: ToyotaLSA_cmcv2

    Chris Tinto, Director, Technical & Regulatory Affairs
    Toyota Motor North America, Inc.
    1850 M Street, NW Suite 600
    Washington, DC 20036


    Dear Mr. Tinto:

    This responds to your request for an interpretation regarding the proper positioning of a leg support system during a crash test specified in Federal Motor Vehicle Safety Standard (FMVSS) No. 208, Occupant crash protection. As explained below, Toyota is correct in its understanding that the leg support system described in your letter is to be adjusted as an "other seat adjustment" under FMVSS No. 208.

    On May 12, 2000, the National Highway Traffic Safety Administration (NHTSA) published a final rule in the Federal Register requiring advanced air bags in all passenger cars, multi-purpose vehicles, light trucks and buses with a gross vehicle weight rating (GVWR) of 8,500 lb or less (65 FR 30680; Advanced air bag rule). That final rule established new, advanced air bag performance requirements to minimize the risk of injury to children, as well as new requirements to enhance the protection of small and mid-size adults. The advanced air bag rule established a rigid barrier dynamic crash test using a 5th percentile adult female test dummy. Since the advanced air bag rule was established, the agency has amended FMVSS No. 208 on several occasions, in part to provide clearer and more objective test procedures for use of the 5th percentile adult female in testing.

    In your letter, you explained that the Toyota Motor Corporation (Toyota) has developed a "leg support adjustment system (LSA)," which extends the forward edge of a seat cushion to provide additional support to the thighs of taller occupants. As further described in a conversation between Mr. Chris Calamita of my staff and Ms. Christina Mullen of Toyota, the system extends the front trim of the seat by mechanical means. As additionally explained in your letter, the LSA is engaged by an occupant through an adjustment switch on the side of a seat. Your letter then asked if the LSA would be adjusted according to S16.2.10.2, Other seat adjustments, under the FMVSS No. 208 test procedure for the rigid barrier 5th percentile female crash test.

    S16.2.10 of FMVSS No. 208 provides the specifications for the driver and passenger seat set-up conditions for the rigid barrier 5th percentile female crash test. S16.2.10.1, Lumbar support adjustment, specifies the proper position for lumbar support adjustments. S16.2.10.2 specifies the proper positioning of seat adjustments that provide additional support, other than a lumbar support adjustment. As originally adopted in the advanced air bag rule, this provision specifically referred to seat cushion and seat back side bolster adjustments.

    In response to the advanced air bag rule, a manufacturer asked what would be required for vehicles with seat cushions that could be lengthened or shortened. In response, the agency amended the seat positioning procedure to specify the position for adjustable seat parts that provide the occupant additional support (66 FR 65376; December 18, 2001). The December 2001 final rule amended S16.2.10.2 to read:

    Other seat adjustments. Position any adjustable parts of the seat that provide additional support so that they are in the lowest or most open adjustment position.

    The LSA, as described in your letter, performs the same type of function as the seat cushion which gave rise to the amended S16.2.10.2. Therefore, that section specifies the position of the LSA.

    Based on the diagrams you provided, it appears that the forwardmost edge of the seat cushion is higher in relation to the floor pan when the LSA is extended as opposed to when the LSA is fully retracted. S16.2.10.2 specifies that a vehicle equipped with an LSA would be tested with the LSA in the lowest position. Therefore, if we were to test a vehicle equipped with a LSA, we would place the LSA in its shortest and lowest position.

    I hope you find this helpful. If you have any additional questions please contact Mr. Calamita at (202) 366-2992.

    Sincerely,

    Jacqueline Glassman
    Chief Counsel

    ref:208
    d.8/27/04