A hydrostatic test is the most common way in which leaks can be found in pressure vessels such as pipelines and plumbing. Using this test helps maintain safety standards and durability of a vessel over time. Newly manufactured pieces are initially qualified using the hydrostatic test and continually re-qualified at regular intervals using the proof pressure test which is also called the modified hydrostatic test. Hydrostatic testing is also a way in which a gas pressure vessel such as a gas cylinder or a boiler is checked for leaks or flaws. Testing is very important because such containers can explode if they fail when containing compressed gas.