(a) The following refueling hardware specifications apply for any nozzle installation used for dispensing gasoline into motor vehicles:
(1) The outside diameter of the terminal end must not be greater than 21.3 mm.
(2) The terminal end must have a straight section of at least 63 mm.
(3) The retaining spring must terminate at least 76 mm from the terminal end.
(b) For nozzles that dispense gasoline into motor vehicles, the dispensing flow rate must not exceed a maximum value of 10 gallons per minute. The flow rate may be controlled through any means in the pump/dispenser system, as long as it does not exceed the specified maximum value. Any dispensing pump dedicated to heavy-duty vehicles or airplanes is exempt from this flow-rate requirement.