TEXAS IRRIGATOR LICENSE EXAM
2020: BACKFLOW QUESTIONS WITH
COMPLETE ANSWERS
Air Gap ✅✅correct answ-Gap through air between lowest point of water supply & flood level rim.
i.e. Sink water level & faucet
Anti-Siphon Device ✅✅correct answ-Any device that introduces air into the system to prevent
back siphonage.
AVB (Atmospheric Vacuum Breaker) or PVB (Pressure-type Vacuum Breaker)
Atmospheric Vacuum Breaker (AVB) ✅✅correct answ-Blackflow device that allows air with use of
a float.
Shape: Like an L
Back Pressure: No
Constant Pressure: No more than 12 hrs in 24-hr period.
Install Height: Vertically with min of 6" higher than all downstream piping and highest downstream
head.
Install: No shut-off valves downstream. Must be on discharge side of each control valve.
Backflow ✅✅correct answ-Unwanted reversal of water flow
2020: BACKFLOW QUESTIONS WITH
COMPLETE ANSWERS
Air Gap ✅✅correct answ-Gap through air between lowest point of water supply & flood level rim.
i.e. Sink water level & faucet
Anti-Siphon Device ✅✅correct answ-Any device that introduces air into the system to prevent
back siphonage.
AVB (Atmospheric Vacuum Breaker) or PVB (Pressure-type Vacuum Breaker)
Atmospheric Vacuum Breaker (AVB) ✅✅correct answ-Blackflow device that allows air with use of
a float.
Shape: Like an L
Back Pressure: No
Constant Pressure: No more than 12 hrs in 24-hr period.
Install Height: Vertically with min of 6" higher than all downstream piping and highest downstream
head.
Install: No shut-off valves downstream. Must be on discharge side of each control valve.
Backflow ✅✅correct answ-Unwanted reversal of water flow
