51. No person may hang on to or be pulled or pushed by a moving vehicle, or ride in or on any part of the vehicle that is not a place designed for a passenger.
It is prohibited for a passenger to stand in or on a sleigh or trailer towed by a moving off-highway vehicle.
It is prohibited for an operator to tolerate the performance of the actions mentioned in the first and second paragraphs when operating the vehicle.
No person may be carried in a sleigh or trailer towed by an off-highway vehicle unless the sleigh or trailer complies with the standards regulating their manufacturing and securing, as the case may be.
The Government may prescribe, by regulation, any other conditions and restrictions applicable to passenger transportation. The regulation may, in particular, provide for restrictions concerning modifications to a vehicle to allow for more passengers.