86Supply of air or vacuum to brakes

86 Supply of air or vacuum to brakes

86 Supply of air or vacuum to brakes

(1) If air brakes are fitted to a heavy vehicle—

(a) the vehicle’s air brake compressor must be able to build up air pressure to at least 80% of the vehicle’s governor cut-out pressure in not more than 5 minutes after the compressed air reserve is fully used up; and

(b) the air storage tanks in the vehicle’s braking system must have sufficient capacity to allow 5 applications of the service brakes before the air pressure drops below half the vehicle’s governor cut-out pressure; and

(c) there must be, at the lowest point of each air brake reservoir in the vehicle’s braking system—

(i) a manual condensate drain valve; or

(ii) an automatic condensate drain valve that also allows water to be removed from the compressed air reserve manually; and

(d) any spring brake fitted to the vehicle must not operate before the warning mentioned in section 90(4)(a) or 93(3)(a) has been given.

(2) If vacuum brakes are fitted to a heavy vehicle, the vacuum supply must be able to build up vacuum—

(a) to the level when the warning signal mentioned in section 90(4)(a) or 93(3)(a) 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.

(3) In this section—

compressed air reserve, in relation to a vehicle, means compressed air stored on the vehicle for the purpose of supply to 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, in relation to 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 1 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 the purpose of supply to the vehicle’s braking system.