Taken from the road traffic lighting regulations
Exemptions—General
4.—(1) Where a provision is applied by these Regulations to a motor vehicle first used on or after a specified date it does not apply to any vehicle manufactured at least six months before that date.
(2) Where an exemption from, or a relaxation of, a provision is applied by these Regulations to a motor vehicle first used before a specified date it shall also apply to a motor vehicle first used on or after that date if it was manufactured at least six months before that date.
(3) Nothing in these Regulations shall require any lamp or reflector to be fitted between sunrise and sunset to-
(a) a vehicle not fitted with any front or rear position lamp,
(b) an incomplete vehicle proceeding to a works for completion,
(c) a pedal cycle,
(d) a pedestrian-controlled vehicle,
(e) a horse-drawn vehicle,
(f) a vehicle drawn or propelled by hand, or
(g) a combat vehicle.
(4) Without prejudice to regulation 16, for the purposes of these Regulations a lamp shall not be treated as being a lamp if it is-
(a) so painted over or masked that it is not capable of being immediately used or readily put to use; or
(b) an electric lamp which is not provided with any system of wiring by means of which that lamp is, or can readily be, connected with a source of electricity.
