Interpretation ID: nht87-3.23

TYPE: INTERPRETATION-NHTSA

DATE: 11/09/87

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: Karl F. Milde, Jr.

TITLE: FMVSS INTERPRETATION

TEXT:

Karl F. Milde, Jr., P.C. Law Office RFD #8, Box 369 Union Valley Road Mahopac, NY 10541

Dear Mr. Milde:

This is in reply to your letter of October 2 1987 with reference to an electronic circuit that would automatically activate a vehicle's hazard warning system when the vehicle is proceeding slowly, or has stopped in the roadway. You have asked whether suc h a system has been proposed before, or field tested, and whether federal Motor Vehicle Safety Standard No. 108 would permit its installation on motor vehicles.

The traffic hazard that concerns you, especially that presented by a vehicle that has stopped in the roadway without activation of either brakes or hazard warning system, is one that is familiar to many motorists. However, it appears that in actuality mo st motorists confronted with this hazard are able to react in time to avoid a rear end collision. Accident data available to the agency indicate that crashes of this nature are relatively rare. As you know, many States require activation of the hazard wa rning system at speeds less than 40 mph on the Interstate system. NHTSA has not proposed a system of this nature, nor has it field tested one. The agency has participated in research with deceleration warning systems, a similar though not identical conce pt, and concluded that safety benefits were insufficient to propose their adoption.

We see no Federal prohibition against installation of a circuit that would activate the hazard warning system at a predetermined low rate of speed. Equipment that is not prescribed by the lighting standard is permissible as original equipment as long as it does not impair the effectiveness of equipment that Standard No. 108 does require. And modifications of vehicles in use by persons other than the vehicle owner are permissible as long as they do not render inoperative, in whole or in part, vehicle equ ipment necessary for compliance with a Federal motor vehicle safety standard. Not are we aware of any State restrictions on the use of such Q system, though you should consult the American Association of Motor Vehicle Administrators for a definitive answ er. Its address is 1201 Connecticut Avenue, M, Washington, DC 20036.

Sincerely, Erika Z. Jones Chief Counsel

October 2, 1987 CERTIFIED MAIL, RRR

Erica Z. Jones, Esq. Chief Counsel National Highway Traffic Safety Administration Room 5219 400 7th Street, Southwest Washington, D.C. 20590

Re: Automatic Hazard light for motor vehicles Dear Ms. Jones:

Brian O'Neill of the Insurance Institute for Highway Safety suggested that I write to you and request your comments on the memorandum.

In particular, I respectfully request your answers to the following two questions:

(1) Has an automatic hazard light been proposed before? If so, has its effectiveness been field tested?

(2) Does the federal Standard 108, as presently formulated, permit the installation of an automatic hazard light on a motor vehicle?

Your comments on any prior experience with this safety device as well as your "interpretation letter" on its legality would be greatly appreciated.

Very truly yours, Karl F. Milde, Jr. Enclosure cc: Mr. Brian O'Neill

MEMORANDUM

TO: N H T S A FROM: Karl F. Milde, Jr. DATE: October 1, 1987 RE: Automatic Hazard Light

I would like to alert you to a traffic hazard that has plagued me personally, many times, and which can be completely eliminated by a simple electronic circuit on a motor vehicle:

Frequently, the vehicle in which a motorist is driving - call it "vehicle 2" - is proceeding down a highway at a normal highway speed: e.g., 30-55 MPH. The vehicle of another motorist - call it "vehicle 1" - is stopped or is proceeding very slowly on the same highway ahead of vehicle 2. (There may be any number of reasons why the vehicle 1 has stopped or proceed slowly: the operator of vehicle 1 may intend to turn left after oncoming cars have passed; there may be traffic congestion ahead of vehicle 1; or vehicle 1 may be disabled with an overheated engine, flat tire or the like.) Normally, the operator of vehicle 1 will have applied the brakes so that the brake lights of vehicle 1 are illuminated, alerting the operator of vehicle 2. Often, however, th e operator of vehicle 1 does not have a need to apply the brakes because vehicle 1 has either stopped or is proceeding slowly at a steady speed. Alternatively, the operator of vehicle 1 can switch on flashing "hazard" lights, but this requires positive a ction on the operator' s part which is frequently forgotten. In the absence of any warning lights, the operator of vehicle 2 may not notice that vehicle 1 has stopped or is proceeding slowly until it is too late to prevent vehicle 2 from colliding with t he rear of vehicle 1.

There is a simple solution to this all-too-frequent traffic hazard: namely, an electronic circuit which will automatically switch on the hazard lights of a motor vehicle when this vehicle is detained (has stopped or proceeds slowly) on a highway.

With such a circuit the hazard lights will warm the drivers of vehicles approaching from the rear, even though the operator of the motor vehicle has forgotten to manually actuate the hazard light switch.

Such a circuit could not possibly cost more than a couple of dollars and, if every vehicle were so equipped, many accidents (and personal injuries) could be avoided.

As an example, I am attaching a newspaper report of a truck driver who failed to notice that traffic had stopped in front of him on the New Jersey Turnpike. The consequence was fatal. Had the cars ahead of him been flashing hazard lights, the truck drive r would surely have brought his vehicle to a safe stop.