Interpretation ID: nht71-5.16

DATE: 12/08/71

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Holophane Company, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of October 27, 1971, to David H. Soule of the National Highway Traffic Safety Administration concerning the requirements of Motor Vehicle Safety Standard No. 108 for school bus lighting.

You are concerned with paragraph S4.3.4(b)(ii) which roads:

"The system shall be wired so that the amber signal lamps are activated only by manual or foot operation, and if activated, are automatically deactivated and the red signal lamps automatically activated when the bus entrance door is opened."

You have commented that "the use of the automatic system would make it mandatory that the red lights go on when the door is open and stop traffic where unnecessary -- such as railroad crossings." That is not correct. You will see from S4.1.4(b)(ii) that the red lamps are not automatically activated when the bus entrance door opens unless there has been prior manual or foot activation of the amber signal lamps.

You are also concerned with the fact "that this automatic system is patented and only one manufacturer has the right to make it." Since you have not enclosed the copy of the patent enclosed in attorney Smith's letter to you dated June 4, 1970, I am unable to comment on your statement. I would like to point out that Standard No. 108 does

not mandate the use of an amber-red lamp system; a system of red lamps only is also permissible. If the amber-red lamp system is used, paragraph S4.1.4(b)(ii) does not specify system design but only that the system be wired so that the driver can activate the amber lamp system at his option, and if he does activate it, that it automatically be deactivated and the red system automatically activated when the bus entrance door is opened.