What is a pressure/vacuum decay test?
Pressure decay testing measures the change in pressure between atmospheric pressure and your pressurized test sample. Unlike some other current methods of leak testing, this test method yields quantitative information, hard data points that can be recorded and upon which decisions can be made. This removes the dependency upon the operator and allows specific accept/reject criteria to be set, and this method is quite simple to use. It is fast; 2-4 second cycles are achievable, keeping in mind that test time is volume dependent. Pressure decay testing is as sensitive as the time available for the test. Pressure decay may include vacuum testing since a “vacuum” is merely a pressure below atmosphere. All references to “pressure decay” hereafter are equally applicable to “vacuum decay” testing. Guiding Equations and Relationships The following fundamental equations are essential to measure leakage and work with pressure decay testing. where V is the volume of the medium exiting or entering
