45. Every vessel containing residual hazardous materials shall be closed, shall be impermeable where used outdoors, and shall be sturdy, in good condition and designed to retain its contents; it shall be made of material that cannot be altered by the material stored therein.
Notwithstanding the foregoing, in order to prevent any accident risk, receptacles may be equipped with a safety valve and cargo containers, tanks and cargo tanks may be equipped with vents.