31.5. A liquefied petroleum gas cylinder installed on the outside of a vehicle must be protected if installed at the rear of the vehicle by extending the bumper beyond the cylinder using materials having a resistance at least equal to that of the bumper.
A liquefied petroleum gas cylinder may not be installed on the roof of a vehicle, in front of the front axle of a motor vehicle or on a door of the vehicle and may not extend beyond the sides of the vehicle.