USC Tester Training Course
What type of backflow protection, if any, would be needed to protect an irrigation system
feeding uphill with no chemical injection system? - ANS-Reduced pressure principle
assembly (RP)
At sea level, 74.7 psia is the same as 60.0 psig. - ANS-60.0 psig + atmospheric
pressure (14.7) = 74.7 psia
Name 2 means of protecting against a direct cross connection to a pollutant. - ANS-Air
gap. Reduced pressure principle assembly (RP). Double check valve assembly (DC)
What are the installation requirements for a pressure vacuum breaker or a spill resistant
pressure vacuum breaker assembly? - ANS-Installed at least 12" above all downstream
piping and outlets.
Not subject to back pressure.
May be used to protect against a pollutant or contaminant.
What are the installation requirements for an atmospheric vacuum breaker? -
ANS-Installed at least 6" above all downstream piping and outlets.
Not subject to back pressure
Maybe used to protect against a pollutant or contaminant.
No downstream shutoff valves.
Non continuous use (Not more than 12 hours out of a 24 hour period)
Why is a vacuum breaker a common means of internal backflow protection? -
ANS-Used for back siphonage only
Cost
Why would an irrigation system without a chemical injection system be considered a
high hazard? - ANS-Contaminated water pooling around sprinkler heads
What is the difference between internal protection and system protection? -
ANS-Internal protection protects the internal plumbing system at each cross connection
on the premises at the point of water use
System protection protects the water distribution system by placing the backflow
preventer at the service connection
What type of backflow protection, if any, would be needed to protect an irrigation system
feeding uphill with no chemical injection system? - ANS-Reduced pressure principle
assembly (RP)
At sea level, 74.7 psia is the same as 60.0 psig. - ANS-60.0 psig + atmospheric
pressure (14.7) = 74.7 psia
Name 2 means of protecting against a direct cross connection to a pollutant. - ANS-Air
gap. Reduced pressure principle assembly (RP). Double check valve assembly (DC)
What are the installation requirements for a pressure vacuum breaker or a spill resistant
pressure vacuum breaker assembly? - ANS-Installed at least 12" above all downstream
piping and outlets.
Not subject to back pressure.
May be used to protect against a pollutant or contaminant.
What are the installation requirements for an atmospheric vacuum breaker? -
ANS-Installed at least 6" above all downstream piping and outlets.
Not subject to back pressure
Maybe used to protect against a pollutant or contaminant.
No downstream shutoff valves.
Non continuous use (Not more than 12 hours out of a 24 hour period)
Why is a vacuum breaker a common means of internal backflow protection? -
ANS-Used for back siphonage only
Cost
Why would an irrigation system without a chemical injection system be considered a
high hazard? - ANS-Contaminated water pooling around sprinkler heads
What is the difference between internal protection and system protection? -
ANS-Internal protection protects the internal plumbing system at each cross connection
on the premises at the point of water use
System protection protects the water distribution system by placing the backflow
preventer at the service connection
