Interpretation ID: nht89-2.43

TYPE: INTERPRETATION-NHTSA

DATE: 07/24/89

FROM: STEPHEN P. WOOD -- NHTSA ACTING CHIEF COUNSEL

TO: WAYNE KRAUSE -- ENGINEERING SUPERVISOR WALTCO TRUCK EQUIPMENT COMPANY

TITLE: NONE

ATTACHMT: LETTER DATED 06/21/89 FROM WAYNE KRAUSE -- WALTCO TO STEVEN P. WOOD -- NHTSA; OCC 3668

TEXT: Dear Mr. Krause:

This is in reply to your letter of June 21, 1989, asking for an interpretation of Federal Motor Vehicle Safety Standard No. 108.

You have enclosed drawings of a rear lighting configuration (tail, stop, and turn signal lamps) intended for installation of your "RGL-Series tail gate lift with the platform stored below floor level of a truck or trailer for transit". You state that the platform in this position would block from view any normal taillamp arrangement, and that in order to comply with the 45 degree visibility requirement of Standard No. 108, you propose to use two sets of lamps. "Light Set 1 is installed above floor leve l (not to exceed 72" for ground) and inside of tail gate rails." The other, "Light Set 2 will be installed under the vehicle body. . . ." Light Set 1 would be visible "from the rear of the vehicle and would act as the primary tail lights." The other arra ngement, Light Set 2, "would act as auxiliary tail lights that would be visible from the side of the vehicle. . . ." You believe that such a configuration is acceptable under paragraph S4.3.1.1.1 (now S5.3.1.1.1) of Standard No. 108, and ask for our comm ents.

Paragraph S5.3.1.1.1 states in pertinent part:

[E]ach lamp shall . . . shall be located so that it meets the visibility requirements specified in any applicable SAE Standard or Recommended Practice. . . . . However, if motor vehicle equipment . . . prevents compliance with this paragraph by any r equired lamp . . . an auxiliary lamp . . . meeting the requirements of this paragraph shall be provided.

While you have developed a novel concept to address the lighting problem posed by the RGL Series, it is not one that is permitted by paragraph S5.3.1.1.1, or by the SAE Standards incorporated by reference in Standard No. 108. The paragraph clearly st ates that "each" lamp shall meet the visibility requirements, and if the vehicle configuration prohibits that, then an auxiliary lamp "meeting the requirements of this paragraph" shall be provided. The basic SAE visibility requirement applicable to lamp s in the array is that they be visible through a horizontal angle from 45 degrees to the left to 45 degrees to the right. This means that if the primary lamp does not meet the visibility requirements, the auxiliary lamp must, and the requirements cannot be met through partial compliance of each lamp. Neither appears to meet the total visibility requirements of Standard No. 108 applicable to each lamp, and thus such a configuration would not meet Federal lighting requirements.

Sincerely,