Paragraph 5 I1

Any gas container must be capable of being isolated from its supply pipework by means of an isolation valve connected directly to each gas container but not between the gas container and its pressure relief device.

Any isolation valve must be capable of shutting off all the gas flow from the gas container, except through the pressure relief device.

Any isolation valve must be marked clearly and permanently with the direction of operation.

Any isolation valve must be so protected as to ensure that its operation is unaffected by the collection of moisture and other foreign matter.

Any gas container valve assembly must be so placed as, so far as is practicable, to be protected from damage.

In this paragraph “isolation valve” means a manually operable isolation valve.