The gas test pressure to be used shall not be less than ______ times the proposed maximum working pressure.

• A. Two times
• B. One time
• C. One and one-half times
• D. Three times

Answer: (C)

During a gas piping test, you want to prove the system can handle more than it will see in normal operation. The proposed maximum working pressure is the highest pressure the piping is designed to carry in service. Setting the test pressure to 1.5 times that value provides a safe margin: it’s high enough to reveal leaks and weak joints that might not show up at normal pressure, but not so high that it risks damaging components. Testing at only the operating pressure could miss latent defects, while a much higher pressure could unnecessarily stress or injure the piping. So the gas test pressure should be at least 1.5 times the proposed maximum working pressure.