Vacuum Leak Test works in the opposite way of the pressure decay test. This method involves evacuating the part to suitably low pressures and after stabilizing the pressure, measuring the increase in pressure caused by test media entering the part. Only parts that are able to withstand external pressure can be tested in this way (e.g. thin-walled plastic parts cannot be tested due to the danger of collapsing). The vacuum decay method can be realized in a fully automatic procedure and, in this way, it is independent of the operator. This technique is a “go no-go” test. It detects the total system leak and more than one leak can exist; leak location can’t be detected. In a vacuum decay test, the unit to be tested is evacuated and its internal pressure is lower than atmospheric pressure.

Vacuum Leak Test works in the opposite way of the pressure decay test. This method involves evacuating the part to suitably low pressures and after stabilizing the pressure, measuring the increase in pressure caused by test media entering the part. Only parts that are able to withstand external pressure can be tested in this way (e.g. thin-walled plastic parts cannot be tested due to the danger of collapsing). The vacuum decay method can be realized in a fully automatic procedure and, in this way, it is independent of the operator. This technique is a “go no-go” test. It detects the total system leak and more than one leak can exist; leak location can’t be detected. In a vacuum decay test, the unit to be tested is evacuated and its internal pressure is lower than atmospheric pressure.