§ 397.15 Fueling.
When a motor vehicle which contains hazardous materials is being fueled—
(a) Its engine must not be operating; and
(b) A person must be in control of the fueling process at the point where the fuel tank is filled.
49 CFR 397.15
When a motor vehicle which contains hazardous materials is being fueled—
(a) Its engine must not be operating; and
(b) A person must be in control of the fueling process at the point where the fuel tank is filled.