Gas PipingQuestion 230 of 360
For a rough-in pressure test of a new low-pressure gas piping system, which test condition is commonly required by the plumbing code?
a.Air or inert gas at not less than 10 psi held for at least 15 minutes
b.Water at 5 psi for 5 minutes
c.Natural gas at working pressure for 1 hour
d.Oxygen at 50 psi for 10 minutes
Explanation
New gas piping is proof-tested with air or an inert gas, typically at not less than 10 psi held for a minimum of 15 minutes with no drop on the gauge (verify the value required by your local jurisdiction). The medium is never oxygen or fuel gas, and never water, because gas lines must stay dry. A pressure loss during the hold indicates a leak to locate and repair.
Law Reference: California Plumbing Code, Fuel Gas provisionsPractice all 360 questions free — no signup required.
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