The device in question is a double check valve backflow prevention assembly (BPA) that is mandated by the Emerald Coast Utilities Authority and costs between $600 and $850 to install, ...

The CAT-3 DM1 Series E and CAT-4 DM2 Series E-pneumatic double valves exhaust downstream air to help meet the stop-time requirements in machine-guarding applications. The DM1 ...