Gas PipingQuestion 258 of 360
Which test medium is acceptable for pressure-testing gas piping?
a.Air or an inert gas such as nitrogen
b.Pure oxygen
c.The fuel gas itself at full pressure
d.Chlorinated water
Explanation
Gas piping is proof-tested with air or an inert gas such as nitrogen, never with oxygen, which accelerates combustion, and never with the fuel gas itself under test conditions. Water is not used because gas lines must remain dry and clean. Isolate or remove appliances and regulators that could be damaged by the test pressure before charging the system.
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