Article 4

in respect of a vehicle being used for police, fire brigade or ambulance purposes;

to anything done with the permission or at the direction of a constable in uniform or of a traffic warden;

so as to render it unlawful to cause or permit the whole, or any part of a vehicle to remain stationary within the boxed area while waiting to complete a right turn for so long as the vehicle is prevented from completing that turn by reason either of oncoming vehicles or of the presence of other stationary vehicles waiting in or near that area to complete a right turn; or

so as to render it unlawful to cause or permit the whole or any part of a vehicle to remain stationary in the boxed area if, when the whole or any part of the vehicle entered that area, the person so causing or permitting had reason to believe that he would immediately be able to cause or permit the vehicle to be driven out of that area.