Cross-connection control

Question 1

any connection between a potable water system and another fluid system through which contamination could enter the potable water system

Answer 1

cross-connection

Question 2

the flow of any substance back into a potable water system

Answer 2

backflow

Question 3

a condition in which a system that is cross-connected to a potable water system is at a higher pressure than the water system

Answer 3

backpressure

Question 4

the condition under which foreign material is drawn into the water system because the system pressure is less than atmospheric pressure

Answer 4

backsiphonage

Question 5

provides the highest level of protection against backflow

• must be 2 times the inside diameter of the inlet pipe
• minimum gap is 1 in above overflow level

Answer 5

air gap

Question 6

has two spring loaded check valves

• pressure regulated relief valve between check valves
• can be used on all cross-connections-including high hazard

Answer 6

reduced pressure zone backflow preventer (RPZ)

Question 7

designed without the relief valve and no external indication of valve failure
-not recommended where failure may result in health hazard

Answer 7

double check valve assemblies

Question 8

not designed to protect against backpressure

• only used where there is no possibility of backpressure
• installed 6 in above highest point of downstream outlet

Answer 8

atmospheric vacuum breaker (AVB)

Question 9

not designed to protect against backpressure

• two valve assembly
• installed 12 in above highest point of downstream outlet

Answer 9

pressure vacuum breaker (PVB)

Question 10

What are the 4 back flow control devices?

Answer 10

1) Air gap
2) Reduced pressure zone back flow preventer (RPZ)
3) Double check Valve
4) Vacuum breakers ( AVB-atmospheric vacuum breaker, (PVB-Pressure vacuum breaker)