This Standard specifies general requirements for the design, construction, testing, maintenance and inspection of road tank vehicles, irrespective of the cargo, that are intended for the road transport of dangerous goods. The Standard deals with vehicles that are designed and constructed specifically as road tank vehicles. It is applicable also to conventional vehicles that are to carry portable or demountable tanks or tank containers which are filled or emptied whilst on the vehicle and as a consequence are deemed to be a road tank vehicle.