scope:

Description

The purpose of these Assemblies is to allow the release & admission of high volumes of air through air valves & vents in water distribution systems, but prevent the entry of contaminated water when the air valve outlet becomes submerged from flooding or is maliciously tampered. This assembly shall consist of a primary and a secondary chamber that each contain an independent float-operated closure member. The primary chamber is the lower chamber. The secondary or upper chamber is redundant and will close in the event the primary chamber fails to close.