AWWA C512:2007
AWWA C512:2007 Air Release, Air/vacuum, And Combination Air Valves For Waterworks Service Specifies 1/2-in. (13-mm) through 6-in. (150-mm) air-release valves and 1/2-in. (13-mm) through 20-in. (500-mm) air/vacuum and combination air valves having gray cast-iron or ductile-iron bodies and c