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Chapter 19: Backflow Prevention and Cross-
Connection Control Questions and Answers with
100% Complete Solutions UPDATED!!!
Backflow - ANSWER Flow of water, foreign liquids, gases into a
potable water system.
Conditions that cause backflow - ANSWER backpressure and
backsiphonage
Backpressure - ANSWER condition in which a substance is
forced into a water system due to higher pressure than system
pressure
backsiphonage - ANSWER condition in which pressure in the
distribution is less than atmospheric pressure (main is under
vacuum)
cross-connection - ANSWER any connection or structural
arrangement between a potable water system and any other
source in which backflow may occur.
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cross-connection sources - ANSWER exists if a connection leads
from a potable line to anything other than a potable service
CC category - ANSWER actual or potential
actual cc - ANSWER connection exists at all times
potential cc - ANSWER something must be done to complete
the connection
back-flow due to back-pressure - ANSWER re-circulation of
potable or non-potable water for the purposes of fire demand
or processing requirements
backflow due to backsiphonage - ANSWER caused by
atmospheric pressure, maximum height water can be siphoned
is 10.3 m or 33.9 feet sea level.
common backsiphonage cause - ANSWER overpumping by a fire
or booster pump or undersized distribution piping (creates high
velocity of water, which causes severe pressure drops)
Chapter 19: Backflow Prevention and Cross-
Connection Control Questions and Answers with
100% Complete Solutions UPDATED!!!
Backflow - ANSWER Flow of water, foreign liquids, gases into a
potable water system.
Conditions that cause backflow - ANSWER backpressure and
backsiphonage
Backpressure - ANSWER condition in which a substance is
forced into a water system due to higher pressure than system
pressure
backsiphonage - ANSWER condition in which pressure in the
distribution is less than atmospheric pressure (main is under
vacuum)
cross-connection - ANSWER any connection or structural
arrangement between a potable water system and any other
source in which backflow may occur.
, 2|Page
cross-connection sources - ANSWER exists if a connection leads
from a potable line to anything other than a potable service
CC category - ANSWER actual or potential
actual cc - ANSWER connection exists at all times
potential cc - ANSWER something must be done to complete
the connection
back-flow due to back-pressure - ANSWER re-circulation of
potable or non-potable water for the purposes of fire demand
or processing requirements
backflow due to backsiphonage - ANSWER caused by
atmospheric pressure, maximum height water can be siphoned
is 10.3 m or 33.9 feet sea level.
common backsiphonage cause - ANSWER overpumping by a fire
or booster pump or undersized distribution piping (creates high
velocity of water, which causes severe pressure drops)
