Interpretation ID: nht92-3.30

DATE: October 2, 1992

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Dan Trexler -- Thomas Built Buses

TITLE: None

ATTACHMT: Attached to letter dated 9/14/92 from Paul Jackson Rice to Lyle Walheim (Std. 131) and letter dated 8/10/92 from Dan Trexler to Paul Jackson Rice (OCC-7641)

TEXT:

This responds to your letter requesting an interpretation of the requirements set forth in Federal Motor Vehicle Safety Standard No. 131, School Bus Pedestrian Safety Devices. I am pleased to have this opportunity to respond to your questions about requirements addressing the activation of a stop signal arm and the permissibility of a manual override device. In addition, I am enclosing a September 14, 1992 interpretation letter from this agency to the Wisconsin Department of Transportation, which explains these requirements.

As your letter indicates, there are two different types of lamp systems on school buses: a four lamp system with four red lamps and an eight lamp system with four amber and four red lamps. You asked several questions about the stop arm's activation and the manual override device.

You first ask whether the stop arm is required to extend every time the signal lamps in a four lamp system are activated. (emphasis in original). As a general rule, S5.5 of Standard No. 131 requires that the stop arm be automatically extended at a minimum whenever the red signal lamps are activated. Nevertheless, Standard No. 131 includes an exception to this general rule which permits the installation of an override device. If the override device were activated, then the stop arm would not extend.

Your second question addresses the operation of the stop arm on buses with an eight lamp system. Specifically, you ask whether the stop arm is required to extend only after the red signal lamps have been activated by opening of the bus entrance door or is the stop arm required to extend at any time the red signal lamps are activated. (emphasis in original).

As stated above, Standard No. 131 includes provisions addressing the activation of the stop signal arm. Standard No. 131 requires the stop arm to be automatically extended whenever the red signal lamps are activated, whether those lamps are activated by opening the bus door or for some other reason. Of course, the stop arm may be extended for a longer period of time than when the red signal lamps are activated, given that Standard No. 131 includes the phrase "at a minimum" in explaining when the stop arm must be extended. In the final rule establishing Standard No. 131, the agency addressed methods of stop arm activation used by Washington State, Illinois, and Florida in which the stop arm was activated to control traffic before the door was opened. (56 FR 20363, 20368, May 3, 1991).

Your third question asked whether a device may be used that is capable of remaining in the "override" position with only a one time activation by the driver. The override would have an audible signal that would automatically

sound for at least 60 seconds and would automatically recycle each time the service door was opened, with the engine running. As mentioned above, Standard No. 131 permits a device that prevents the automatic extension of the stop signal arm. In our September 14, 1992 letter to Mr. Lyle Walheim from the State of Wisconsin, we explain a situation in which an override would be permissible. Based on S5.5 of Standard No. 131 and the September 14, 1992 interpretation to Mr. Walheim, it would appear that the override device you describe also would be permissible.

I hope this information is helpful. If you have any further questions about NHTSA's safety standards, please feel free to contact Marvin Shaw of my staff at this address or by telephone at (202) 366-2992.