Mr. Dietmar K. Haenchen
    Safety Affairs and Vehicle Testing
    Mail Code 3C02
    3800 Hamlin Road
    Auburn Hills, MI 48326

    Dear Mr. Haenchen:

    This responds to your letter requesting clarification of Federal Motor Vehicle Safety Standard (FMVSS) No. 206, Door locks and door retention components. Specifically, you have asked whether the back door requirements apply to latch systems on a hinged window that is integrated into the back door. For the system described in your letter, the answer is no. This system is not subject to FMVSS No. 206s back door requirements because the standard is designed to address latch systems on doors rather than windows.

    As you are aware, the National Highway Traffic Safety Administration (NHTSA) administers a statute requiring that motor vehicles manufactured for sale in the United States or imported into the United States be manufactured so as to reduce the likelihood of motor vehicle crashes and of deaths and injuries when crashes do occur. We refer to that statute as the Vehicle Safety Act. It is codified at 49 U.S.C. 30101, et seq.

    One of the agencys functions under the Vehicle Safety Act is to issue and enforce FMVSSs. These standards specify safety performance requirements for motor vehicles and/or items of motor vehicle equipment. Manufacturers of motor vehicles must certify compliance with all applicable safety standards and permanently apply a label to each vehicle stating that the vehicle complies with all applicable FMVSSs.

    FMVSS No. 206 specifies certain performance requirements for door retention components, including those on back doors. The definition of a back door, contained in S3 of the standard, states:

    Back door means a door or door system on the back end of a motor vehicle through which passengers can enter or depart the vehicle, or cargo can be loaded or unloaded; but does not include:

    (a) a trunk lid; or
    (b) a door or window that is composed entirely of glazing material and whose latches and/or hinges are attached directly to the glazing material.

Your question relates specifically to a system consisting of a back door that would fully comply with the requirements of FMVSS No. 206, but which has a window integrated into the door that rotates away from the vehicle when opened. The window would be supported by a thin metal or plastic frame and have hinges or latches that are attached to either the thin frame or directly to the piece of glazing.

You are concerned that because the window would incorporate a latch/hinge design, it would be considered a back door under the standard, and the latch would be regulated by FMVSS No. 206 unless exempt under subpart (b) of the back door definition. As explained more fully below, based on the information you have provided, it appears that the window would not be considered a back door.

In excluding doors and windows "composed entirely of glazing material" NHTSA was referring to large pieces of glazing that act as a back door, not window glazing that is mounted in and framed by a metal door (see letter of interpretation to General Motors Corporation, dated May 6, 1996). NHTSA decided to exempt windows composed entirely of glazing because many back doors incorporate a design whereby the back door system consists of a lower, metal tailgate and an upper piece of glazing that is not surrounded by a metal frame sufficiently strong to retain a door latch or hinge component in a crash. The piece of glazing is joined directly to the vehicle structure via a set of hinges and the latch is married to a striker positioned in the tailgate or the frame of the vehicle. As originally proposed, such a design would have required each piece of attachment hardware to meet the newly proposed back door requirements (59 FR 44691, August 30, 1994). In response to industry comments, NHTSA acknowledged that it was unreasonable to expect retention hardware to meet the requirements of the standard when the glazing surrounding such hardware could not reasonably be expected to restrain an occupant in a crash. Thus, the exemption for doors or windows consisting entirely of glazing was crafted.

As discussed in the May 1996 letter of interpretation to General Motors referenced above, the relevant criterion in determining whether the latches or hinges are directly attached to glazing is if the glazing constitutes the principal structural component of the door or window. Based on the information provided in your letter, we believe the design you have presented is entirely glazing material with a small frame added solely for structural support fro the glazing. Because the thin metal or plastic frame described in your letter would not be the principal structural component of the door or window, the latches and/or hinges would be considered directly attached to the glazing structure. Thus, the latch of this design is not subject to the standard.

Because the window system discussed in your letter would not qualify as a type of glazing considered by NHTSA to constitute a door, there is no need to further evaluate whether the window could be used to load or unload cargo, or whether the attachment hardware is attached directly to the piece of glazing. However, I caution you that the standard does not speak to doors that are typically used to load cargo, as indicated in your letter, but rather to doors through which cargo "can be loaded or unloaded".

Should you require any additional information or assistance, please contact Rebecca MacPherson, of my staff, (202) 366-2992 or at the address given above.


Jacqueline Glassman
Chief Counsel