On oil tankers, required to be fitted with inert gas systems, suitable connections for the supply of inert gas shall be provided on double hull spaces.
Where necessary, fixed purge pipes arranged such to take into account the configuration of these spaces shall be fitted.
Where such spaces are connected to a permanently fitted inert gas distribution system, suitable means (e.g. a second water seal and check valve) shall be provided to prevent cargo vapours entering the double hull space.
Where no permanent distribution system is installed, a sufficient number of means for connecting to these spaces shall be provided on the inert gas main.