Mr. Junichi Yoshimoto
Deputy General Manager
Technical Administration Dept.
Koito Mfg. Co., Ltd.
Shizuoka Works
500, Kitawaki
Shimuzu-Shi, Shizuoka-Ken

Dear Mr. Yoshimoto:

This replies to your letter of July 7, 1997, asking for an interpretation of the headlighting requirements of Federal Motor Vehicle Safety Standard No. 108.

Your letter contains a drawing of a headlamp with two light sources, two separate lens and separate aimable reflectors and one housing. You have asked whether a pair of these units would be regarded as a two-lamp or a four-lamp headlighting system for purpose of compliance with the photometric requirements of Figure 15 (four lamps) or Figure 17 (two lamps).

Because the two light sources are in a single housing, we regard your drawing as showing a single headlamp. Therefore, a system consisting of two of these lamps would be a two-lamp system, required to comply with the photometric requirements of Figure 17.

John Womack
Acting Chief Counsel