Tank vehicles, tank containers, portable tanks, special vehicles or containers or vehicles or containers specially prepared, for which a mark is required for elevated temperature substances under special provision 580 as is indicated in column (6) table A of Chapter 3.2 shall, on each side and the rear vehicle in the case, and on all four sides in the case of containers, tank containers or portable tanks, a triangular shaped mark with sides of at least 250 mm, to be shown in red.