Ms. Alison Vredenburgh
Vice President
Research and Development
Error Analysis, Inc.
Suite 205
5811 Amaya Drive
La Mesa, CA 91942-4156

Dear Ms. Vredenburgh:

This is in reply to your letter of September 18, 1995, to Kenneth Hardie of this agency, with respect to the Motorcycle Conspicuity Enhancement System (the "System") described in your letter. You understand "that this system may only be used during daylight hours and may not affect the headlight", and you ask if there are any other regulations of which you should be aware.

We understand that the System is still under development, and that the intent is to offer it both as original and aftermarket equipment. Two Systems will be tested, at a flash rate of 60 to 80 per minute, one at an intensity of 35,000 candlepower, and the other at 50,000 candlepower. One System will have three bulbs, and another, four. Each System will be activated when the headlamp is on. We note that motorcycle headlamps are wired to be activated when the ignition is on because many States require that headlamps be operating at all times.

As you know, each motorcycle must be manufactured and certified to conform to all applicable Federal motor vehicle safety standards, including Standard No. 108 Lamps, Reflective Devices, and Associated Equipment. Standard No. 108 prescribes no requirements for supplemental equipment such as the System. However, additional lighting equipment may not be installed by the manufacturer or dealer before sale if the supplemental equipment impairs the effectiveness of lighting equipment required by Standard No. 108 (paragraph S5.1.3).

You are therefore correct when you say that the System "may not affect the headlamp." One way in which the System could impair the effectiveness of the headlamp is if it continued to operate at a time when the headlamp is required to provide sufficient illumination of the roadway (as you recognize in your comment that "the system may only be used during daylight hours"). You have not described the method by which the

System will be deactivated. We believe that this should not be a manual operation, left to the discretion of the motorcycle operator. In establishing the specifications that allow optional installation of modulating headlamp systems for improving the conspicuity of motorcycles, this agency requires that they be equipped with a sensor that will deactivate the modulation when a certain low ambient light level is reached. Also, the modulation rate is regulated to prevent seizures in susceptible individuals. I enclose a copy of paragraph S5.6 of Standard No. 108 which discusses these light levels.

The System must also not impair the effectiveness of the motorcycle's front turn signals. That is to say, it must not mask the signal or detract from its detectability by oncoming drivers. Whether this might occur will depend upon the color and brightness of the System and its proximity to the turn signal lamp.

If a motorcycle manufacturer is satisfied that the installation of the System on its product would be permissible under S5.1.3, then it may certify that the motorcycle conforms to all applicable Federal motor vehicle safety standards. NHTSA will not question a determination of non-impairment unless it appears to be clearly erroneous.

Satisfaction of Federal new vehicle requirements means that the System is acceptable for sale in the aftermarket under Federal regulations. However, supplementary lighting equipment, whether original or aftermarket, that is not specifically covered by Standard No. 108 remains subject to regulation by the States. We note that many States have vehicle equipment and use regulations regarding auxiliary amber flashing lamps, Many States also prohibit blue as a color for lamps, reserving it for police, fire, and emergency vehicles. We are unable to advise you on the specifics of State laws, and urge you to consult the American Association of Motor Vehicle Administrators, 4600 Wilson Boulevard, Arlington, Va. 22203.

If you have any further questions, you may refer them to Taylor Vinson of this Office (202-366-5263).


Samuel J. Dubbin Chief Counsel

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