138Braking system design for trailers in B-doubles or road trains

138 Braking system design for trailers in B-doubles or road trains (1) The performance of the service, secondary and parking brake systems of a trailer used in a B-double or road train must comply with second edition ADR 38 or third edition ADR 38 if the trailer would not otherwise be required to comply with an ADR about braking. (2) A road train trailer to which subrule (1) applies need not be fitted with a mechanical parking brake if it carries wheel chocks that provide a performance equal to the performance standard required for a parking brake system. (3) A semi-trailer, regardless of when it was built, must have an anti- lock braking system that complies with third edition ADR 38/01, if: (a) it is being used in a B-double that includes a road tank vehicle, whether or not the semi-trailer is itself a road tank vehicle; and (b) the road tank vehicle is carrying dangerous goods.