97. No motor vehicle shall be used on a road in such manner as to cause any excessive noise which could have been avoided by the exercise of reasonable care on the part of the driver.
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.
99.—(1) Subject to the following paragraphs, no person shall sound, or cause or permit to be sounded, any horn, gong, bell or siren fitted to or carried on a vehicle which is—
(a)stationary on a road, at any time, other than at times of danger due to another moving vehicle on or near the road; or
(b)in motion on a restricted road, between 23.30 hours and 07.00 hours in the following morning.
(2) The provisions of paragraph (1)(a) do not apply in respect of the sounding of a reversing alarm when the vehicle to which it is fitted is about to move backwards and its engine is running.
(3) No person shall sound, or cause or permit to be sounded, on a road any reversing alarm fitted to a vehicle—
(a)unless the vehicle is a goods vehicle which has a maximum gross weight not less than 2000 kg, a bus, engineering plant, or a works truck; or
(b)if the sound of the alarm is likely to be confused with a sound emitted in the operation of a pedestrian crossing established, or having effect as if established, under Part III of the 1984 Act.
(4) Subject to the provisions of the following paragraphs, no person shall sound, or cause or permit to be sounded a gong, bell, siren or two-tone horn, fitted to or otherwise carried on a vehicle (whether it is stationary or not).
(5) Nothing in paragraph (1) or (4) shall prevent the sounding of—
(a)an instrument or apparatus fitted to, or otherwise carried on, a vehicle at a time when the vehicle is being used for one of the purposes specified in regulation 37(5) and it is necessary or desirable to do so either to indicate to other road users the urgency of the purposes for which the vehicle is being used, or to warn other road users of the presence of the vehicle on the road; or
(b)a horn (not being a two-tone horn), bell, gong or siren—
(i) to raise alarm as to the theft or attempted theft of the vehicle or its contents; or
(ii) in the case of a bus, to summon help for the driver, the conductor or an inspector.
(6) Subject to the provisions of section 62 of the Control of Pollution Act 1974 and notwithstanding the provisions of paragraphs (1) and (4) above, a person may, between 12.00 hours and 19.00 hours, sound or cause or permit to be sounded an instrument or apparatus, other than a two-tone horn, fitted to or otherwise carried on a vehicle, being an instrument or apparatus designed to emit a sound for the purpose of informing members of the public that the vehicle is conveying goods for sale, if, when the apparatus or instrument is sounded, it is sounded only for that purpose.
(7) For the purposes of this regulation the expressions which are referred to in regulation 37(10) have the meanings there given to them and the expression “restricted road” in paragraph (1) means