When performing a hydrostatic test on a boiler, what must be done regarding safety valves?

During a hydrostatic test on a boiler, the standard practice is to remove or gag all safety valves. This is essential because the purpose of the hydrostatic test is to assess the integrity of the boiler under pressure, which is typically higher than the operating pressure. If safety valves were left in place, they could potentially open during the test due to the increased pressure, leading to inaccurate test results and possible injury or equipment damage.

Removing or gagging the safety valves ensures that they do not interfere with the test, allowing the operator to safely evaluate the boiler's ability to withstand the hydrostatic pressures without the risk of premature valve operation. This measure is crucial to avoid misinterpretation of the boiler’s condition and to ensure compliance with safety regulations during the testing procedure.