In 1942 a mass spectrometer was used for the first time as leak tester. This was for the Manhatten-Project. Today Helium-Leak-Tester are used for a wide range of leak test applications in production and laboratory.
The detection of Helium coming from a leakage by the mass spectrometer requires high vacuum (p < 10-4mbar). Meanwhile there are Helium sensor which can detect Helium also at atmosphere pressure. However, the highest sensitivity is still reached by the mass spectrometer.
For this reason we distinguish:
HELT-V (Helium-Leak-Tester-Vacuum): Helium leak test methods and machines using a mass spectrometer as detector which requires the high vacuum
HELT-A (Helium-Leak-Tester-Atmosphere): Helium leak test methods and machines using other sensor technology which can be used at atmosphere pressure.
You will find more information under HELT-V und HELT-A.
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