Interpretation ID: aiam1772
Liaison Engineer
British Leyland Motors Inc.
600 Willow Tree Road
Leonia
NJ 07605;
Dear Ms. Black: This is in response to your letter of December 19, 1974, requestin interpretations of two test conditions contained in Standard No. 301-75, *Fuel System Integrity*.; Your first question relates to the static rollover test condition an asks whether it was the NHTSA's intention that the vehicle be rotated to three positions only for spillage measurement. (Paragraph S7.4 specifically refers only to increments of 90 degrees, 180 degrees, and 270 degrees.) The static rollover test is intended to test the amount of fuel spillage a vehicle experiences at each 90 degree increment in a full 360 degree rotation. The standard presumes that the test begin with the vehicle in an upright position. It is from this upright position that the vehicle begins its movement to the remaining three 90 degree increments.; Your second question asks for an interpretation of the section relatin to the operation of the vehicle's fuel pump during testing. Paragraph S7.1.3 of the standard requires that a electrically driven fuel pump be in operation during the barrier crash tests if it normally operates with the activation of the vehicle's electrical system. If pump operation requires the operation of the vehicle's engine, ten (sic) the pump should not be running during the barrier crash tests. If the fuel pump installed in your barrier is capable of independent operation as described in SF.1.3 it should be operating during the barrier crash tests even if it cuts off fuel at the moment of impact. Under the existing requirements, whether a pump out of fuel at impact would not be relevant to whether it must be operating at impact. Of course, over cutoff feature would be considered as pard of the bump's normal operation.; Yours truly, Richard B. Dyson, Acting Chief Counsel