Part 8Braking systems

Part 8—Braking systems This Part sets out the braking system requirements for vehicles to ensure that they can be reliably slowed or stopped even if a part of a braking system fails, and to ensure that a vehicle can be prevented from rolling away when parked. Division 1—Brake requirements for all vehicles 119 Parts of a braking system A brake tube or hose fitted to a vehicle must— (a) be manufactured from a material appropriate to its intended use in the vehicle; and (b) be long enough to allow for the full range of steering and suspension movements of the vehicle; and (c) be fitted to prevent it being damaged during the operation of the vehicle by— (i) a source of heat; or (ii) any movement of the parts to which it is attached or near. 120 Provision for wear The braking system of a vehicle must allow for adjustment to take account of normal wear. 121 Supply of air or vacuum to brakes ***air brake compressor****,* of a vehicle, means a compressor for supplying air to the vehicle's air brakes; ***compressed air reserve***, for a vehicle, means compressed air stored on the vehicle for supplying the vehicle's braking system; ***condensate drain valve*** means a device used to remove water from the compressed air reserve for a vehicle fitted with air brakes; ***governor cut-out pressure****,* of a vehicle, means the air pressure at which the vehicle's air brake compressor stops supplying air to the vehicle's air brake reservoir; ***spring brake*** means a brake using one or more springs to store the energy needed to operate the brake; ***vacuum reserve****,* in relation to a vehicle, means air at a low pressure stored on the vehicle for supplying the vehicle's braking system. (2) If air brakes are fitted to a vehicle— (a) the compressor supplying air to the brakes must be able to build up air pressure to at least 80% of the governor cut‑out pressure in not over 5 minutes after the compressed air reserve is fully used up; and (b) there must be an automatic or manual condensate drain valve at the lowest point of each air brake reservoir in the system; and (c) any spring brake fitted to the vehicle must not operate before the warning mentioned in clause 128(3)(a) of this Schedule has been given. (3) If vacuum brakes are fitted to a vehicle, the vacuum supply must be able to build up vacuum— (a) to the level when the warning signal mentioned in clause 128(3)(a) of this Schedule no longer operates within 30 seconds after the vacuum reserve is fully used up; and (b) to the normal working level within 60 seconds after the vacuum reserve is fully used up. 122 Performance of braking systems (1) One sustained application of the brake of a motor vehicle built after 1930, or a combination that includes a motor vehicle built after 1930, must be able to produce the performance referred to in subclauses (2) to (7)— (a) when the vehicle or combination is on a dry, smooth, level road surface, free from loose material; and (b) whether or not the vehicle or combination is loaded; and (c) without part of the vehicle or combination moving outside a straight path— (i) centred on the longitudinal axis of the vehicle or combination before the brake was applied; and (ii) 3·7 metres wide. (2) The braking system of a motor vehicle or combination with a gross mass under 2·5 tonnes must bring the vehicle or combination from a speed of 35 kilometres per hour to a stop within— (a) 12·5 metres when the service brake is applied; and (b) 30 metres when the emergency brake is applied. (3) The braking system of a motor vehicle or combination with a gross mass of at least 2·5 tonnes must bring the vehicle or combination from a speed of 35 kilometres per hour to a stop within— (a) 16·5 metres when the service brake is applied; and (b) 40·5 metres when the emergency brake is applied. (4) The braking system of a motor vehicle or combination with a gross mass under 2·5 tonnes must decelerate the vehicle or combination, from any speed at which the vehicle or combination can travel, by an average of at least— (a) 3·8 metres a second a second when the service brake is applied; and (b) 1·6 metres a second a second when the emergency brake is applied. (5) The braking system of a motor vehicle or combination with a gross mass of at least 2·5 tonnes must decelerate the vehicle or combination, from any speed at which the vehicle or combination can travel, by an average of at least— (a) 2·8 metres a second a second when the service brake is applied; and (b) 1·1 metres a second a second when the emergency brake is applied. (6) The braking system of a motor vehicle or combination with a gross mass under 2·5 tonnes must achieve a peak deceleration of the vehicle or combination, from any speed at which the vehicle or combination can travel, of at least— (a) 5·8 metres a second a second when the service brake is applied; and (b) 1·9 metres a second a second when the emergency brake is applied. (7) The braking system of a motor vehicle or combination with a gross mass of at least 2·5 tonnes must achieve a peak deceleration of the vehicle or combination, from any speed at which the vehicle or combination can travel, of at least— (a) 4·4 metres a second a second when the service brake is applied; and (b) 1·5 metres a second a second when the emergency brake is applied. (8) The parking brake of a vehicle or combination must be able to hold the vehicle or combination stationary on a 12% gradient— (a) when the vehicle or combination is on a dry, smooth road surface, free from loose material; and (b) whether or not the vehicle or combination is loaded. Division 2—Motor vehicle braking systems 123 What braking system a motor vehicle must have ***independent brake***, for a vehicle, means a brake that is operated entirely separately from any other brake on the vehicle, except for any drum, disc or part, on which a shoe, band or friction pad makes contact, that is common to 2 or more brakes. (2) A motor vehicle with 4 or more wheels built, or used, mainly for transporting goods or people by road must be fitted with— (a) a braking system that— (i) consists of brakes fitted to all wheels of the vehicle; and (ii) has at least 2 separate methods of activation, arranged so effective braking remains on at least 2 wheels if a method fails; or (b) 2 independent brakes, each of which, when in operation, acts directly on at least half the number of wheels of the vehicle. (3) The braking system of a motor vehicle referred to in subclause (2) that was built after 1945 must have a service brake operating on all wheels that, when applied— (a) acts directly on the wheels and not through the vehicle's transmission; or (b) acts on a shaft between a differential of the vehicle and a wheel. (4) The braking system of a motor vehicle with 4 or more wheels must have a parking brake that— (a) is held in the applied position by direct mechanical action without the intervention of an electrical, hydraulic or pneumatic device; and (b) is fitted with a locking device that can hold the brake in the applied position; and (c) has its own separate control. (5) The parking brake may also be the emergency brake. (6) If 2 or more independent brakes are fitted to a motor vehicle with 4 or more wheels, the brakes must be arranged so brakes are applied to all the wheels on at least one axle of the vehicle when any brake is operated. (7) A motor cycle or motor trike must be fitted with— (a) 2 independent brakes; or (b) a single brake that acts directly on all wheels of the vehicle and is arranged so effective braking remains on at least one wheel if a part of the system fails. (8) Subclause (7) applies to a motor cycle with a sidecar attached as if the sidecar were not attached. (9) A motor trike must have a parking brake that is held in the applied position by mechanical means. 124 Operation of brakes on motor vehicles The braking system on a motor vehicle must be arranged to allow the driver of the motor vehicle to apply the brakes from a normal driving position. 125 Air or vacuum brakes on motor vehicles (1) If a motor vehicle has air brakes, the braking system of the vehicle must include at least one air storage tank. (2) If a motor vehicle has vacuum brakes, the braking system of the vehicle must include at least one vacuum storage tank. (3) An air or vacuum storage tank must be built so the service brake can be applied to meet the performance standards of clause 122 of this Schedule at least twice if the engine of the vehicle stops or the source of air or vacuum fails. (4) An air or vacuum storage system must— (a) be built to give a visible or audible warning to the driver, while in a normal driving position, of a lack of air or vacuum that would prevent the service brake from being applied to meet the performance standards of clause 122 of this Schedule at least twice; and (b) be safeguarded by a check valve or other device against loss of air or vacuum if the supply fails or leaks. (5) If air or vacuum brakes are fitted to a motor vehicle equipped to tow a trailer, the brakes of the vehicle must be able to stop the vehicle, to meet the performance standards for emergency brakes under clause 122 if the trailer breaks away. Division 3—Trailer braking systems