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Interpretation ID: nht75-2.48

DATE: 07/17/75

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA Z. VINSON FOR RICHARD B. DYSON -- NHTSA

TO: D. R. Bernard, Esq.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of May 28, 1975, providing further information for our determination whether certain "safety lights" would violate the National Traffic and Motor Vehicle Safety Act of 1966.

There is no Federal prohibition against sale of this accessory in the aftermarket. It would, however, be subject to regulation by the states. For the following reasons, it could not be used as original equipment. Standard No. 108 requires a minimum spacing of 4 inches (edge to edge) between the stop lamps and the rear turn signal lamps and a minimum spacing of 9 inches (centerline to centerline) between the turn signals. The purpose of this spacing is to provide a distinctive indication of the turning direction. A flashing stop lamp located in close proximity to the steady-burning stop lamp required by Standard No. 108 would, in our opinion, impair the effectiveness of the rear turn signal within the meaning of S4.1.3, during a combined braking and turning operation. Such a lamp would also be prohibited by S4.6(b) which, in effect, requires all original equipment stop lamps to be steady burning.

Yours truly,

ATTACH.

BERNARD & BERNARD -- ATTORNEYS AT LAW

May 28, 1975

Richard B. Dyson -- Assistant Chief Counsel, U.S. Department of Transportation, National Highway Traffic Safety Administration

Re: N40-30 (ZTV)

Dear Mr. Dyson:

Pursuant to your letter, we are providing the following supplemental information in order for you to reach a decision in regard to the proposed safety lights.

1. The flashing lights will be no brighter than the standard brake light, but will be mounted in close proximity to the said brake lights.

2. The flashing lights will be a different color from the turn signals and will not interfere with the operation nor be confused with the turn signals.

3. The flashing lights will be the same color normally as the brake lights and will have a frequency of flashes approximately twice the speed of the signal light for turns.

It is hoped that this information will be satisfactory to you, and your conclusion as soon as possible would be appreciated.

Yours truly,

D. R. Bernard