This document specifies: a) field of application; b) requirements for pipe interrupters with permanent atmospheric vent; c) dimensional, the physico-chemical properties and the properties of general hydraulic, mechanical and acoustic design of pipe interrupters with permanent atmospheric vent, DN 10 to DN 20; d) test method and requirements for verifying these properties; e) marking and presentation; f) acoustics. This document specifies the characteristics of pipe interrupters with permanent atmospheric vent, DN 10 to DN 20 that are suitable for use in drinking water systems at pressures up to 1 MPa (10 bar) and temperatures up to 65 °C and for 1 h 90 °C. Backflow protection devices integrated in flushing valves are similar to DC and are not covered under this document. The requirements are stated in EN 12541.