Interpretation ID: 1985-04.35

TYPE: INTERPRETATION-NHTSA

DATE: 11/25/85

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: Mr. John L. O'Connell

TITLE: FMVSS INTERPRETATION

TEXT:

November 25, 1985 Mr. John L. O'Connell Public Transportation Administrator Department of Motor Vehicles State of Connecticut State Street Wethersfield, CT 06109-1896 Dear Mr. O'Connell: This is in reply to your letter of October 8, 1985, to Jeffrey Miller, former Chief Counsel of this agency. You have asked whether a new style school bus warning lamp system developed by the Whelen Engineering Company meets the requirements of Motor Vehicle Safety Standard No. 108 and referenced SAE standards, and whether such a system can be installed and used on school buses in compliance with Federal regulations. Pursuant to paragraph S4.1.4 of Standard No. 108, a school bus must be equipped with a system of red lamps, or red and amber lamps meeting SAE Standard J887 School Bus Red Signal Lamps, July 1964 (copy enclosed). The Whelen system is said to comply with SAE J887 May 1982, with the possible exception of dimensions. The requirements that the Whelen system must meet are those of the 1964 version of J887. Dimensional specifications are not included in the 1964 version, however, the minimum effective projected luminous lens area requirement of 19 square inches must be met. The test report indicates that the Whelen lamp meets the minimum photometrics of both the 1982 and 1964 versions of J887 and its dimensions, 7" x 2.75", indicate that the minimum luminous lens area requirement may also be met. However, the test report indicates that the light flashes at a rate of 55 cycles per minute. The Whelen lamp therefore does not comply with the 1964 requirement that school bus warning lamps flash at a rate of 60-120 cycles per minute (nor the 1982 SAE specifications of 1-2 H which is 60-120 cycles per minute). For this reason, the Whelen system does not meet Federal requirements and cannot be installed on school buses certified as meeting all applicable Federal motor vehicle safety standards. Sincerely, Original Signed By Erika Z. Jones Chief Counsel Enclosure