Pressure vessels are a piece of equipment which stores pressurized fluid to meet the different needs in the industry of continuous process, as in the chemical, petrochemical, petrol or the nuclear, food, electricity generation industries and others.

There are several types of pressure vessel applications, which have different shapes and sizes due to the essential function which is pressurized fluid containment, without leakage. Hydrostatic Tests or Pressure Tests are applied in pressure vessels and other pressurized industrial equipment as tanks or pipelines, in order to check the possibility of leakage or rupture.

They are done with out of service equipment, with water pressurization (Hydrostatic Test), compressed air (Pneumatic Test) or some other available fluid, under higher pressure when compared to the operating one or in the project, usually at 1.5 more than MAWP.

A stricter operating situation is simulated, which aims no failure or leakage will happen at normal service (at lower pressure). Water is usually used as fluid in the Pressure Test (TH Hydrostatic Test) due to availability in process industries.