Atmospheric Vacuum Breaker (AVB)
- An AVB must be installed on each irrigation zone. Control valves (on/off valves) are not allowed downstream of (after) an AVB.
- Each AVB must be installed a minimum of 6" above the highest point of water in the zone it serves.
- No chemical or fertilizer may be introduced into a sprinkler system equipped with AVBs.
- No pumps or back pressure sources are permitted on downstream side of (after) an AVB.
Pressure Vacuum Breaker Assembly (PVB)*
- Only one PVB is required to serve the whole system. Control valves may be located downstream of (after) the PVB.
- PVBs must be installed a minimum of 12" above the highest point of water they serve.
- No chemical or fertilizer may be introduced into an irrigation system equipped with PVBs.
- No pumps or back pressure sources are permitted on downstream side of (after) a PVB.
*Must test every three years or after installation, repair or replacement.
Reduced Pressure Backflow Assembly (RPBA)*
- Only one RPBA is required to serve the whole system; control valves can be located downstream of (after) the RPBA.
- RPBAs must be installed a minimum of 12" above ground level.
- In a RPBA-equipped system, fertilizer and other agricultural chemicals may be introduced downstream of (after) the RPBA.
- List of certified testers.
*Must test every three years or after installation, repair or replacement.