Interpretation ID: aiam4745
Inc. 1203 Woodridge Ave. Ann Arbor
MI 48105;
Dear Mr. Oseki: This is in reply to your letter of April 10, l990, wit respect to the use of the hazard warning system concurrently with the stop lamps to provide additional warning to vehicles to the rear. You enclosed two interpretations of the agency which appear to be conflicting, and you have asked for a clarification. In our letter of June 16, l983, we informed Safety Alert Company that its flashing deceleration warning system could operate through any rear lighting system that Standard No. 108 allows to be used for signalling purposes, such as the turn signal or hazard warning system, provided that the color of light or photometrics required by the standard was not changed. However, in our letter of December 8, 1986, we informed Flxible Corporation that their flashing deceleration warning system was unacceptable under Standard No. 108 because 'simultaneous use of flashing (amber) and steady-burning lamps have the potential for creating confusion in vehicles to the rear of the bus, and impairing the effectiveness of the required stop lamps within the meaning of S4.1.3.' We do not believe that there is a conflict. The system described in the Safety Alert letter would utilize a vehicle's original lighting equipment that is intended to flash, and that the motoring public is accustomed to seeing flash. The system described in the Flxible letter, on the other hand, would employ a series of new lamps, not required by the standard but supplemental to the required lighting equipment, and whose presence and function would be unfamiliar to motorists following. Thus, that unfamiliar system, if flashing, could have a confusing effect, as we stated in our l986 letter. I hope that this clarifies the matter for you. Sincerely, Stephen P. Wood Acting Chief Counsel;