What is the term for the testing of plumbing systems under pressure?

The correct term for testing plumbing systems under pressure is the hydrostatic test. This type of testing involves filling the plumbing system with water and pressurizing it to a specified level. The primary purpose of a hydrostatic test is to identify leaks and ensure that the system can withstand the pressures it will encounter in service.

During the hydrostatic test, the water in the system acts as a medium to detect any leaks. If a leak is present, it will manifest as a drop in pressure, which can be monitored during the test. This method is commonly used for new piping systems and is considered a reliable means of verifying the integrity of the system before it is put into operation.

While pneumatic tests, leak tests, and pressure tests all involve assessing a plumbing system for integrity and the presence of leaks, the hydrostatic test specifically refers to the method of using water as the testing medium, differentiating it from tests that might use air or other gases.