Interpretation ID: nht95-1.97

TYPE: INTERPRETATION-NHTSA

DATE: March 10, 1995

FROM: Jeffrey Echt -- President, Saline Electronics, Inc.

TO: Chief Counsel, NHTSA

TITLE: NONE

ATTACHMT: ATTACHED TO 4/24/95 LETTER FROM PHILIP RECHT TO JEFFREY ECHT (STD. 108)

TEXT: Dear Chief Counsel,

Thank you for your March 2, 1995 interpretation clarifying the position of the National Highway Traffic Safety Administration with regard to deceleration warning systems. In the interpretation, you cited paragraph S5.5.10(d) of FMVSS No. 108 as the basi s for prohibiting the flashing of a vehicle's stop lamps. Paragraph S5.5.10(a) of FMVSS No. 108, however, states:

Turn signal lamps, hazard warning signal lamps, and school bus warning lamps shall be wired to flash.

Based on paragraph S5.5.10(a) of FMVSS No. 108 and the fact that hazard warning indicators are commonly used to warn high-speed trailing traffic that a leading vehicle or leading vehicles are moving slowly or stopped, we seek your opinion on the followin g questions:

1. Would a device which automatically activated a vehicle's hazard warning system at the onset of high, braking-induced deceleration and deactivated the hazard warning system upon release of the brake pedal (following automatic activation) be permissibl e under FMVSS 108? This assumes that the device will not prevent activation or cause deactivation of the hazard warning system if the mandatory vehicular hazard warning signal operating unit has been activated by the driver.

2. If such a device is permissible in principle, would the rear lighting configuration of the vehicle on which it was installed affect its permissibility? Specifically, on which of the following vehicles would installation of the device be permissible?

a) a vehicle with red, combined stop/turn signal lamps

b) a vehicle with red stop lamps and separate, red turn signal lamps

c) a vehicle with red stop lamps and separate, amber turn signal lamps

Once again, we appreciate your consideration of our request and thank you for your prompt action. As before, Saline Electronics, Inc. has no objection to this letter and your response to it becoming a part of the public record.

Sincerely,