.-(1) Every vehicle which is engaged in the transport of petroleum by road shall be constantly attended to by at least one person who shall be familiar with the rules in this Part:Provided that such a vehicle, if its tanks for compartments are empty, but not free from petroleum vapour, may be left unattended in places previously approved for the purpose in writing by the Chief Controller.(2)Every vehicle in which more than 5 kilolitres of petroleum, other than petroleum Class C, is being transported by road, or which, while transporting petroleum, other than petroleum Class C by road, is being trailed by another vehicle, shall, so long as it is in motion, be attended to, by the driver and at least one more person both of whom shall be familiar with the rules in this Part.
