392.50—Ignition of fuel; prevention.
         No driver or any employee of a motor carrier shall:
    
    
        
        (a) 
         Fuel a commercial motor vehicle with the engine running, except when it is necessary to run the engine to fuel the commercial motor vehicle;
    
    
    
        
        (c) 
         Fuel a commercial motor vehicle unless the nozzle of the fuel hose is continuously in contact with the intake pipe of the fuel tank;
    
    
        
        (d) 
         Permit, insofar as practicable, any other person to engage in such activities as would be likely to result in fire or explosion.
    
    [33 FR 19732, Dec. 25, 1968, as amended at 60 FR 38747, July 28, 1995]