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    Dr. Ing. Pavel Vokl
    Type Approval Tests and Technical Regulations,
    Patents, Licences and Trademarks
    Technical Development
    SKODA AUTO a.s.
    Tr. Vclava Klementa 869
    293 60 Mlad Boleslav
    Czech Republic

    Dear Dr. Ing. Vokl:

    This responds to your request for an interpretation of Federal Motor Vehicle Safety Standard (FMVSS) No. 104, Windshield wiping and washing systems, and of the definition of "seating reference point" in 49 CFR Part 571.3.You have two questions relating to the 2002 version of Society of Automotive Engineers (SAE) Standard J1100 (SAE J1100), which are addressed below.

    In responding to your letter, I note that the National Highway Traffic Safety Administration (NHTSA) does not provide interpretations of SAE standards alone. SAE standards are developed by the SAE, a private organization. NHTSA has authority to issue and enforce the Federal motor vehicle safety standards.If an SAE standard (in whole or in part) is incorporated by reference by an FMVSS, NHTSA will provide an interpretation of the FMVSS, and any applicable SAE standard included in that FMVSS.

    Your first question relates to FMVSS No. 104. You asked whether, within the intention of SAE J1100, the daylight opening is reduced by the area of the projected internal mirror on the windshield.You state your belief that the area of the projected mirror on the windshield may have influence on the mandatory percentage of the area (especially area A according to FMVSS No. 104) to be wiped.

    Our response is that SAE J1100 is not incorporated by FMVSS No. 104.However, FMVSS No. 104 includes a definition of "daylight opening" that is taken from another SAE standard, paragraph 2.3.12 of section E, Ground Vehicle Practice, SAE Aerospace-Automotive Drawing Standards, September 1963.

    Paragraph 2.3.12 of that SAE standard states:

    The term "Daylight Opening" (abbreviated DLO) refers to the maximum unobstructed opening through any glass aperture, including reveal or garnish moldings adjoining the glass, according to a given direction or projection. If not specified the dimension will be the vertical projection.

    The definition does not provide that the area it describes is to be reduced by the area of the projected internal mirror on the windshield.

    Your second question is whether the 2002 version of SAE J1100 has been incorporated by reference into the definition of "seating reference point" (SgRP) at 49 CFR Part 571.3 Definitions in the FMVSSs.The answer is no, the SgRP definition continues to reference the June 1984 version of SAE J1100.NHTSA has not announced rulemaking to include the 2002 version of SAE J1100 into the definition of SgRP.

    I hope this information is helpful.If you have any further questions, please contact Ms. Dorothy Nakama at this address or at (202) 366-2992.


    Stephen P. Wood
    Acting Chief Counsel