If the maximum system pressure is 180 psi, the hydrostatic test pressure must be at least how many psi?

• A. 200 psi
• B. 230 psi
• C. 180 psi
• D. 250 psi

Answer: (B)

The test pressure is set with a safety margin over the maximum working pressure, so the system is tested well beyond normal operation to catch leaks or weaknesses. In this scenario, the standard used for calculating hydrostatic test pressure is 1.25 times the maximum system pressure.

Compute 1.25 × 180 psi = 225 psi. So the hydrostatic test pressure must be at least 225 psi.

Among the given options, the smallest pressure that meets or exceeds 225 psi is 230 psi, making it the correct minimum hydrostatic test pressure. A value of 200 psi or 180 psi would be too low, and while 250 psi would also be acceptable, it isn’t the minimum that satisfies the requirement.