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Interpretation ID: 20570revised



    Mr. Thomas D. Turner
    Manager, Engineering Services
    Blue Bird Body Company
    P.O. Box 937
    Fort Valley, GA 31030


    Dear Mr. Turner:


    This responds to your request for an interpretation of Standard No. 221, School Bus Body Joint Strength. I apologize for the delay in responding. You ask whether the plastic wire trim parts that Blue Bird is considering using in school buses are parts of body panel joints which must meet the fastener spacing and joint strength requirements of the standard.

    Manufacturers are permitted two alternatives in meeting Standard No. 221. Until May 5, 2001, they may certify school buses manufactured on or after November 5, 1998 as meeting either: (a) requirements that have been in effect prior to a November 5, 1998 final rule (63 FR 59732); or (b) requirements adopted by the November 5, 1998 final rule (see also 65 FR 11751, delaying the mandatory compliance date of the final rule until May 5, 2001).

    Alternative No. 1
    Under the requirements of Standard No. 221 that have been in effect prior to the November 1998 final rule, plastic wire trim parts are not expressly excluded from the standard's joint strength requirements. However, maintenance access panels are excluded from the definition of a "body panel joint," and until May 5, 2001, do not have to meet the standard's joint strength requirements. You state that the plastic wire trim has qualified for the maintenance access panel exclusion and thus has not been subject to the requirements. Assuming your assessment is correct, the parts are excluded as maintenance access panels until May 5, 2001, for buses certified to this alternative.

    Alternative No. 2
    Under the November 5, 1998 final rule, (1) the maintenance access panel exclusion will be narrowed (2) for school buses manufactured on or after May 5, 2001. Nonetheless, the final rule excludes certain school bus body panels and parts from the joint strength requirements of S5.1.1 and S5.1.2 of the standard. The excluded parts include:

    Trim and decorative parts which do not contribute to the strength of the joint, support members such as rub rails which are entirely outside of body panels, doors and windows, ventilation panels, and engine access covers. (S5.2.1(b))

    In the November 5, 1998 final rule, the agency explained why trim parts were excluded:

    Small and complex joints, as well as trim, decorative parts, floor coverings, and molding strips will not be tested. The agency has no data indicating that any injuries have been caused by failure of these small and complex joints or components, and the National Highway Traffic Safety Administration believes that the potential cost of trying to test them would far outweigh any potential safety benefits.

    Blue Bird believes that the plastic wire trim parts in question are "trim and decorative parts which do not contribute to the strength of the joint" and therefore are excluded from the fastener spacing and joint strength requirements of S5.1.1 and S5.1.2. In support of your position, you provided Figure Two, illustrating how you will redesign the area above the passenger side window to meet the new requirements. You also provided the following description of the wire trim parts:

    The headlining panels are being lengthened and flanges are being added to the side window headers to create overlapping longitudinal joints between these components. These joints will be designed and manufactured to comply with the fastener spacing and joint strength requirements of S5.1.1 and S5.1.2. The wire molding panels are being eliminated and replaced with smaller, non-metallic, non-hostile, plastic wire trim. This wire trim will be in short sections and will cover the wiring harnesses behind them as well as the Federal motor vehicle safety standard 221 complying joints between the headlining panels and the side window headers.

    We have reviewed Blue Bird's description of the plastic wire trim parts and the figures provided with the letter. We agree that the plastic wire trim parts at issue do not contribute to the structural integrity or the joint strength of the bus. As such, they would be excluded from the requirements of S5.1.1 and S5.1.2. This exclusion only applies to school buses that are manufactured on or after November 5, 1998, and certified as meeting this compliance alternative, i.e., the requirements set forth in the November 5, 1998, final rule.

    I hope this information is helpful. If you have any further questions, please feel free to contact Dorothy Nakama of my staff at this address or at (202) 366-2992.


    Sincerely,


    Frank Seales, Jr.
    Chief Counsel

    ref:221
    d.8/31/00

    1. In brief, Standard No. 221 requires: (a) body panels attached to each other to have no unattached segment at the joint longer than 203 mm (S5.1.1); and (b) each body panel joint to hold each body panel to the component to which it is joined when subjected to a force that equates to 60 percent of the tensile strength of the weakest joined body panel (S5.1.2).

    2. The requirements of S5.1.1 and S5.1.2 do not apply to any interior maintenance access panel which lies forward of the passenger compartment, or which is less than 305 mm when measured across any two points diametrically on opposite sides of the opening (S5.2.1(a)).