Interpretation ID: aiam1780
Truck Body & Equipment Assoc.
5530 Wisconsin
(sic) Ave.
Suite 1220
Washington
DC 20015;
Dear Mr. Crampton: This responds to your January 3, 1975, question whether a firefightin vehicle which articulates and has a configuration similar to that a conventional truck-trailer combinations qualifies as a 'truck' for test purposes under Standard No. 121, *Air brake systems*. You describe the vehicle as a tractor trailer aerial ladder with articulating portions that cannot be uncoupled, and with permanently-connected air brake lines and hydraulic pressure lines between the articulating sections.; The vehicle you describe is a 'truck' as that term is defined in 49 CF S 571.3, *Definitions*. The rear articulated portion does not qualifiy (sic) as a 'trailer' as defined in S571.3, because the permanent connection to the truck tractor prevents it from standing alone as a 'vehicle'. Therefore, the tractor trailer aerial ladder would be tested as a truck under Standard No. 121. It is noteworthy that the lighting requirements which apply to the rear portion of this vehicle are those for trucks under Standard No. 108, *Lamps reflective devices, and associated equipment*.; Yours truly, Richard B. Dyson, Assistant Chief Counsel