For use below ground level with SBS and leak gas test device. Enables automatic leak gas testing of the entire system before each commissioning. See "Safety rules for piping work". Section 5.5.3 Order no. ZH 1/559 from the German Federation of Institutions for Statutory Accident Insurance and Prevention and VBG 43 § 39 - Para. 4 Implementation instructions for UW heating, scarfing and melting equipment for construction and assembly work.