This document specifies:a)field of application;b)requirements for in line anti-vacuum valves;c)dimensional, the physico-chemical properties and the properties of general hydraulic, mechanical and acoustic design of in-line anti-vacuum valves DN 8 to DN 80;d)test method and requirements for verifying these properties;e)marking and presentation;f)acoustics.This document specifies the characteristics of in-line anti-vacuum valves DN 8 to DN 80 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 at 90 °C.