Abstract: A device detects leaks in a test object (1), which is contained in a test container (2). The device includes a mass spectrometer (14) detecting a noble gas such as helium, and a pump arrangement containing a primary vacuum pump (13) and a spiromolecular pump (11). The noble gas atoms flow through the latter in opposition to the pump direction towards the mass spectrometer. Between the test container (2) and an outlet port (10) of the spiromolecular pump (11), an accumulation chamber (8) is inserted, whose volume is considerably larger than that of the test container (2). The test container is provided with a source of purge gas (3) and a valve (4) for purging the test container with a purge gas under an adjustable overpressure. Closure valve (7) is disposed between the test container (2) and the accumulation chamber (8) and a closure valve (9) between the accumulation chamber (8) and the outlet port (10) of the spiromolecular pump (11).

Abstract: The invention relates to a method of leak testing a test container. A tracer gas such as helium is sprayed around the test container on its outside, and the inside of the container is evacuated and connected to a tracer gas detector. Prior to the actual leak test, the test container (1) is temporarily connected to a water tank (7) containing water free from dissolved gases.

Abstract: The invention resides in a method for analyzing gases according to the counterflow principle, comprising a mass spectrometer tube (3) located at the suction side of a molecular pump (2). The primary vacuum pressure is adjusted in such a way that basically ambiguous spectrometer indications can only result from a gas with low molecular weight reaching the mass spectrometer in counterflow to the molecular pump and not from a gas with higher molecular weight, which in itself would provoke a similar spectrometer indication.