Western Australian Current Regulations Western Australian Current Regulations (1) The braking system
of a trailer with a GTM of more than 2 t must allow the driver of a motor
vehicle towing the trailer to operate the brakes from a normal driving
position.
(2) However,
subregulation (1) does not apply to an unloaded converter dolly that
weighs less than 3 t if the motor vehicle towing the converter dolly has
a GVM of more than 12 t.
(3) The brakes on a
trailer with a GTM of more than 2 t must —
(a)
operate automatically and quickly if the trailer breaks away from the towing
vehicle; and
(b)
remain in operation for at least 15 minutes after a break‑away; and
(c) be
able to hold the trailer on a 12% gradient while in operation after a
break‑away.