Backflow from Class questions with accurate answers.

Backflow from Class questions with accurate answers
27.75" of water will produce 2psi Ans✓✓✓ False


A double check valve assembly is required at the service if the residence
has an approved well supply on the property. The well water supply in
this case is in no way interconnected with the
community water system. Ans✓✓✓ True


A perfect vacuum at sea level will raise water in a pipe about:


A: 28'
B: 34'
C: 36'
D: 38' Ans✓✓✓ B: 34'


A pressure vacuum breaker backflow preventer is designed to protect the
water supply from pollution under which condition?


A: Backpressure
B: Backsiphonage
C: Water hammer
D: A and B Ans✓✓✓ B: Backsiphonage

,A proper air-gap requires a minimum height of ____ above the flood
rim.
A: 2"
B: 6"
C: 1"
D: 1' Ans✓✓✓ C: 1"


A proper air-gap requires that the minimum height of a water supply line
to be above the overflow rim of a receptacle or basin be ___"


A: 1
B: 6
C: 12
D: 14.7 Ans✓✓✓ A: 1


A PVB must be installed ___.


A: 12" above the highest outlet
B: horizontally
C: 6" above the highest outlet
D: 18" above the highest outlet Ans✓✓✓ A: 12" above the highest
outlet

, A PVB must be installed a minimum height of 20" above the highest
point of industrial water usage. Ans✓✓✓ False


An AVB must be installed ___.


A: 6" above the highest outlet
B: 12" above grade
C: horizontally
D: 12" above the highest outlet Ans✓✓✓ A: 6" above the highest outlet


An AVB must be installed ___.


A: in a pit
B: on the discharge side of a shut-off valve
C: 6" above grade
D: 12" above the highest outlet Ans✓✓✓ B: On the discharge side of a
shut-off valve


An SVB is approved for use in which situations?


A: contaminants with backpressure or backshiphonage
B: contaminants and pollutants with backpressure only
C: contaminants and pollutants with backsiphonage only