scope:

This standard contains information on the testing and purging of industrial and commercial gas installations.

These procedures cover strength and tightness testing, and direct purging, of pipework not exceeding MOP of 16 bar and apply to any section of pipework including any appliance/plant pipework:

• For NG, from the outlet of the ECV (fitted on the end of the gas service that is owned by the GT).
• For LPG, from the outlet of the bulk storage vessel or cylinder valve.
• For other gases on customers' premises, from the outlet of the isolation point from a distribution point.

They apply to strength and tightness testing in the following circumstances:

• New pipework
• Alteration to, replacement of, re-use of, or uprating existing pipework
• New extensions to existing pipework
• Prior to any work on existing pipework
• Where there is a known or suspected gas leak in pipework
• Where there has been a complete loss of pressure for any reason
• Routine testing of existing pipework
• Immediately before purging pipework (except when taking pipework permanently out of service)

And to direct purging in the following circumstances:

• New pipework
• Alteration to, replacement of or re-use of, existing pipework
• New extensions to existing pipework
• Where there has been a complete loss of pressure for any reason
• Where there is the possibility of air being present in pipework
• Where pipework is to be taken out of service temporarily or permanently