1919 Mt. Zion Drive
Golden, CO 80401
Dear Mr. Tunick:
This responds to your letter of July 18, 1994, to Taylor Vinson of this Office, with respect to whether the headlamp system you describe complies with Federal Motor Vehicle Safety Standard No. 108.
The system is comprised of two headlamps. In each lamp, the lower beam will be provided by a gas discharge unit and the upper beam by either one European H-1 unit, or by the H-1 together with the gas discharge unit (or, alternatively, by two gas discharge units). Both lamp units would be sealed in a "box" so that they could not be replaced by the vehicle owner. The "box" would also contain a third light source, mounted outboard of the lower beam gas discharge unit, to be used for purposes other than headlighting.
As you note, this assemblage is an "integral beam headlamp" as defined by S4 of Standard No. 108 because it contains light sources that are neither sealed beam nor replaceable. Thus, it must conform with the requirements of S7.4 Integral Beam Headlighting System. You have noted that the lamp, in fact, will "comply with S7.4(a)(2) and the photometric requirements of either (a)(2)(i) or (a)(2)(ii)", which apply to two- lamp integral beam headlighting systems.
In your view, the lamp meets the requirement of Table IV that the lower beams be mounted "as far apart as practicable" because the configuration of the car body does not permit mounting the gas discharge unit any farther outboard. Further, the lamp "would be in conformity with S7.4(b) as the lamp would have 2 light sources and the lower beam would be provided by the most outboard light source [of those regulated
by Standard No. 108] . . . and the upper beam would be provided by either the most inboard light source or both the gas discharge" and H-1 light sources.
We concur in your conclusion that this system is permissible under Standard No. 108.
John Womack Acting Chief Counsel ref:108 d:7/28/94