Any work performed on a filter, regulator, valve, pressure switch, or flange of the gas train must be followed by a leak test before restarting.
Which points are checked
All loosened connections are checked, as well as adjacent points that may have been stressed during the work.
Gas valves
In addition to external leakage, in certain installations, the internal tightness of the main valves must also be verified via valve proving or a similar procedure.
Regulator
After any intervention on the regulator, both the tightness and the correct outlet pressure must be checked.
Instruments and impulse lines
Small pressure lines and connections for pressure switches or transmitters can also develop leaks.
Restarting
Gas supply is restored only after the test has been successfully completed.
