In „normal“ operation the usability test is done with the purpose of tracking down possible leakages. The gas loss in a pipe can be determined in litre per hour by the instrumentation. Besides -of course- absolute tightness conditions, a loss of less than one litre per hour is still within tolerance and the new installation will be certified an unrestricted usability qualification. Between one and five litres loss means a reduced usability capacity. Further operation is then allowed over a repair time limited to four weeks. Subsequently the full tightness must be verified applying the tightness check. At a loss of five litres or more, the gas pipe will be locked as unsuitable for usability.

For all tests in connection with the TRGI directives, the ecom pressure check kit (DPK) offers the suitable instrumentation including the necessary accessories.