South Australian Consolidated Regulations South Australian Consolidated Regulations139—Air brakes of motor vehicles in B-doubles or road trains
(1) If a B-double or
road train is fitted with brakes that operate using compressed air, the
braking system of the motor vehicle must comply with subrules (2) and (3)
when:
(a) the
pressure is measured in an 800 millilitre vessel connected by a 2 metre pipe
with a bore of approximately 13 millimetres to the coupling head of the
braking system; and
(b) the
air pressure before the brakes are applied is not under:
(i)
the average of the maximum and minimum pressures in the
operating pressure range specified by the vehicle's manufacturer; or
(ii)
if there is no manufacturer's specification—650
kilopascals.
(2) The pressure must
reach at least 420 kilopascals within 400 milliseconds after the rapid and
complete application of the foot-operated brake control.
(3) After the brakes
have been fully applied, the pressure must fall, within half a second after
the release of the foot-operated brake control, to 35 kilopascals.