What is the minimum test pressure of a 0.5 psi gas system?

• A. 2 psi
• B. 3 psi
• C. 4 psi
• D. 5 psi

Answer: (B)

For gas piping, the test pressure must be at least 1.5 times the maximum operating pressure, but not less than 3 psi. Here, the system’s maximum operating pressure is 0.5 psi, so 1.5 times that is 0.75 psi, which is below the required minimum. Therefore, the minimum allowable test pressure is 3 psi. Testing at 2 psi would be below the mandated minimum, while 4 or 5 psi would be higher than the minimum and not needed unless specifically required by the code or design.