This Standard specifies requirements for metallic and plastics bodied PN 10 and PN 16 air valves for sewerage. This Standard is applicable to valve sizes DN 50 to DN 200 suitable for wastewater, with a maximum operating temperature of 60°C (see Note 2).This Standard covers the following types of valves:(a) Large-orifice air valves.(b) Small-orifice air valves.(c) Double-orifice air valves.(d) Anti-slam air valves.NOTES: 1 Purchasing guidelines are given in Appendix B.2 Based upon a maximum sewage temperature of 40°C within the main and the air valve being located above ground exposed to sunlight.3 Alternative pressure classes are available and may be specified.