Gas & FuelQuestion 65 of 110
A newly installed natural-gas piping system is pressure tested before being placed in service. A common test is 3 psi (or 1.5 times working pressure, whichever is greater) held for a set duration. For low-pressure residential piping, what is a typical minimum test pressure and duration?
a.3 psi for at least 10 minutes with no pressure drop
b.1 psi for 5 minutes
c.2 psi for 8 minutes
d.10 psi for 30 seconds
Explanation
A common acceptance test for residential gas piping is 3 psi held for at least 10 minutes (some jurisdictions require longer) with no observable pressure drop on the gauge. The test isolates appliances and uses air or inert gas, never the fuel gas itself. Any drop indicates a leak that must be found and repaired before gas is introduced.
Law Reference: IFGC §406.4Practice all 110 questions free — no signup required.
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