This document specifies:
a) field of application;
b) requirements for hose union backflow preventer;
c) dimensional and the physico-chemical properties and the properties of general hydraulic, mechanical and acoustic design of hose union backflow preventers DN 15 to DN 32;
d) test method and requirements for verifying these properties;
e) marking and presentation;
f) acoustics.
This document specifies the characteristics of hose union backflow preventers DN 15 to DN 32 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.