Interpretation ID: aiam2164
President
The Leithiser Company
145 North Hartley Street
York
Pennsylvania 17404;
Dear Mr. Leithiser: This responds to your November 14, 1975, question whether an air-brake trailer that carries three spools of electric poser line and is designed to pay out and tension the three lines over towers would be required to comply with standard No. 121, *Air Brake Systems*.; Section S3. (*Application*) states in part that '... the standard doe not apply to any trailer whose unloaded vehicle weight is not less than 95 percent of GVWR [gross vehicle weight rating]...' It appears from your description that the trailer in question does not have either a passenger-carrying capacity of a rated cargo load. The unloaded vehicle weight would be equal to the GVWR and the trailer would be excluded from the requirements of the air brake standard.; Yours truly, Richard B. Dyson, Assistant Chief Counsel