What pressure is recommended for testing a hydrant?

• A. 150 psi
• B. 100 psi
• C. 125 psi
• D. 200 psi

Answer: (A)

Testing hydrants relies on applying hydrostatic pressure to verify the hydrant and its connections will hold up under use. The pressure chosen for this test needs to be high enough to reveal leaks or weaknesses, but within what the hydrant and the distribution system are designed to withstand. Using 150 psi provides a safe, standard stress that goes above normal operating pressures while remaining within typical manufacturer and system ratings. It helps ensure components like gaskets, joints, and the valve assembly can handle real-world conditions. A lower pressure, such as 100 psi, wouldn’t reliably expose defects; 125 psi is below the common testing standard; and 200 psi could exceed design limits and risk damage.