Regulation 4
1. In these Regulations “unladen vehicle” means, subject to paragraph 3—
(a)a motor vehicle not drawing a trailer or otherwise forming part of a combination of vehicles; or
(b)a combination of vehicles comprising one motor vehicle drawing one or more trailers,
in relation to which the conditions specified in paragraph 2 below are satisfied.
2. The conditions are—
(a)that the motor vehicle is a motor car, a heavy motor car, or a motor tractor;
(b)that no goods or burden are being carried in the motor vehicle or combination of vehicles; and
(c)that not more than 2 persons (excluding the driver) are being carried in the motor vehicle or combination of vehicles.
3. For the purposes of this Schedule, the following are to be deemed not to constitute goods or burden—
(a)in the case of a motor vehicle constructed or adapted for use and used for the conveyance of a machine or device which is built in as part of the vehicle, that machine or device and any articles used in connection with it;
(b)water, fuel or accumulators used for the purpose of the supply of power for the propulsion of a vehicle or, as the case may be, of any vehicle by which a trailer is drawn, and loose tools and loose equipment.