Helium leak test systems are used for test tasks where evidence of very low leak rates with high accuracy and reproducibility is required. The test method already works at very low test pressure and is suitable for clean and dry test items, which should have no large leaks. The helium leak test is one of the most sensitive test methods, used in integral leak testing and leak detection, whereby usually a test for large leaks has to be carried out beforehand. In the integral leak test, test items are fed semi-automatically or fully automatically to the test chamber, adapted and then enclosed in the test chamber to be evacuated. Helium escaping through leaks in the applied test items is sucked in by a high vacuum pump and detected. The test gas helium is a safe inert gas that can be recovered and reused. Helium air mixtures of any concentration can be used to detect larger leak rates, thereby reducing test gas costs. For integral testing, the workpiece is charged with helium in a vacuum chamber. Helium escaping through leaks is sucked in by a high vacuum pump. At the outlet of the vacuum pump, a helium mass spectrometer detects even the smallest amounts of test gas. Conversely, the chamber can also be flooded with helium and the test object evacuated. For leak detection, the test item is traversed with a helium sniffer probe. Test systems always include a test gas supply with or without recovery, product-specific adaptations, a helium mass spectrometer in conjunction with a high-vacuum pump and a control and evaluation unit. A test chamber, a sniffer probe as well as feeding and handling systems can be added according to the task to be carried out. Semi-automatic or fully automatic test benches and test systems for integral leak testing or leak detection can be realized. Typical test items are heat exchangers, light-alloy wheels, air conditioning and fuel lines, air conditioner generators, brake and fuel system components, fuel tanks, injectors, airbag inflators, sensors, electronics components and assemblies, medical devices, packaging, etc. User branches include the automotive and automotive supply industry and air conditioning.