Type BA – Verifiable backflow preventer with reduced pressure zone

A verifiable mechanical backflow prevention device consisting of an arrangement of water fittings with three pressure zones with differential obturators and that will operate when potential backflow conditions obtain or there is a malfunction of the valve. 

Maximum permissible fluid category against which a Type BA device is accepted as adequate backflow protection:

Backflow by back pressure: fluid category 4

Backflow by back siphonage: fluid category 4

Note: relief ports from Type BA backflow prevention devices shall terminate with an air gap, the dimension of which should satisfy a Type AA air gap. 

Interpretation given in Regulators’ Backflow Specification - backflow prevention arrangements and devices: backflow prevention devices