Note that this standard has been updated and you will need to meet the requirements set out in AS 4945-2000 Commercial road vehicles - Interchangeable quick connect/release couplings for use with air-pressure braking systems.
You may be required to comply with this standard if you operate a long distance interstate road transport business and you intend to use a B-double.
If the B-double uses compressed air as the brake operating fluid, its brake system must include protection against loss of supply line air, or control signal air. The coupling for the hoses for the supply and control lines must be polarised according to the requirements set out in this standard.