Northern Territory Consolidated Regulations Northern Territory Consolidated Regulations(1) Brake line couplings on the same part of a vehicle in a B-double or road train must not be interchangeable.
(2) The couplings must be polarised in accordance with Australian Standard AS D8-1971 Hose Couplings for Use with Vacuum and Air-Pressure Braking Systems on Prime Movers, Trailers and Semi-trailers if the hoses used with the brake couplings are used for the same purpose as the hoses mentioned in the standard.