Tightness tests of objects can be carried out using various techniques. The choice of technique depends on the expected accuracy of the measurement or the magnitude of the leak – the most accurate leak testing technique is the use of a vacuum method with a mass detector. The test is carried out on an object filled with helium, at atmospheric or elevated pressure (up to 250 bar or more), placed in a vacuum chamber connected to a mass detector. The test can detect leaks of the order of 10^-12 mbar*l/s. Using an additional sensor (a sniffer), it is possible to locate points/areas of leakage on the order of 10^-7 mbar*l/s.