Stopping of engine when stationary
98.—(1) Save as provided in paragraph (2), the driver of a vehicle shall, when the vehicle is stationary, stop the action of any machinery attached to or forming part of the vehicle so far as may be necessary for the prevention of noise.
(2) The provisions of paragraph (1) do not apply—
(a)when the vehicle is stationary owing to the necessities of traffic;
(b)so as to prevent the examination or working of the machinery where the examination is necessitated by any failure or derangement of the machinery or where the machinery is required to be worked for a purpose other than driving the vehicle; or
(c)in respect of a vehicle propelled by gas produced in plant carried on the vehicle, to such plant.
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Leaving motor vehicles unattended
107.—(1) Save as provided in paragraph (2), no person shall leave, or cause or permit to be left, on a road a motor vehicle which is not attended by a person licensed to drive it unless the engine is stopped and any parking brake with which the vehicle is required to be equipped is effectively set.
(2) The requirement specified in paragraph (1) as to the stopping of the engine shall not apply in respect of a vehicle—
(a)being used for ambulance, fire brigade or police purposes; or
(b)in such a position and condition as not to be likely to endanger any person or property and engaged in an operation which requires its engine to be used to—
(i)drive machinery forming part of, or mounted on, the vehicle and used for purposes other than driving the vehicle; or
(ii)maintain the electrical power of the batteries of the vehicle at a level required for driving that machinery or apparatus.
(3) In this regulation “parking brake” means a brake fitted to a vehicle in accordance with requirement 16 or 18 in Schedule 3.