BACK FLOW TEST PRACTICE TEST
QUESTIONS AND ANSWERS
what is the difference between check valve 1 and check valve 2 on a double check
valve assembly - Correct Answers -the two check valves operate the same
in a perfect vacuum, water can be drawn up in a column _______ feet - Correct
Answers -33.9
which of the following is considered to be a chemical contaminant? - Correct Answers -
arsenic
which of the following is considered to be a biological health hazard - Correct Answers -
giardia
what type of assembly has two internally spring loaded check, two shut-off valves, and
four test cocks? - Correct Answers -double check valve
air gap is the_________ when directly connecting potable water supply lines to
sewerage systems or to radioactive sources? - Correct Answers -most suitable
protection
a bypass of a backflow prevention assemble may be permitted only if the assembly in
the bypass: - Correct Answers -is the same type
what federal law made water purveyors responsible for water quality all the way into
consumers' homes or businesses? - Correct Answers -safe drinking water act
amendment of 1986
if a column of water is exerting a pressure of 50 psi, how high must the water be inside
the column? - Correct Answers -115.5
as the velocity of water increases, pressure: - Correct Answers -decreases
atmospheric pressure at sea level is _______ psi - Correct Answers -14.7
, a water supply other than the water purveyor's approved supply, that is on or available
to the premises is called a - Correct Answers -auxiliary water supply
how can a backsiphonage action be broken - Correct Answers -air gap
what single difficult to regulate item is most commonly associated with cross
connections, specifically through backsiphonage? - Correct Answers -garden house
the appropriate height fo an air gap is - Correct Answers -twice the diameter of the pipe
above the flood rim of vessel, minimum of 1 inch
while testing check balbe #1 on a DC, water recedes from the tuve attached to test cock
#3. The gauge should be moved to the centerline of the assembly and the static
pressure drop across the no. 1 check should be recorded. What other information
should be recorded. - Correct Answers -check valve #2 is leaking and shutoff valve #2
is leaking
at what point is the relief valve in an RP required to open - Correct Answers -2.0 psid
what is the minimum spring tension recommended on the #1 check valve in an RPZ -
Correct Answers -3 psi greater than the tension on the relief valve.
according to the USC, what is the correct height for installing an RPZ - Correct Answers
-12 inches above grade, but no more than 36 inches
what is the correct height to install a PVB - Correct Answers -12 inches above the
highest downstream point.
what company or agency is responsible for testing and approving all backflow
prevention assemblies in the united states? - Correct Answers -foundation of cross-
connection control & hydraulic research
backflow prevention assemblies are often installed in parallel in order to: - Correct
Answers -maintain service during testing and repairs
which of the following is not a criterion for an approved assembly? - Correct Answers -
shipped by manufacturer in separate parts for inspection
what is the minimum pressure drop across a spring-loaded, soft-seated check valve? -
Correct Answers -1.0 psid
according to usc, what is the correct height to install an atmospheric vacuum breaker? -
Correct Answers -6 inches above the highest downstream point
test kits should be verified for accuracy and, if needed, calibrated how often? - Correct
Answers -at least once a year
QUESTIONS AND ANSWERS
what is the difference between check valve 1 and check valve 2 on a double check
valve assembly - Correct Answers -the two check valves operate the same
in a perfect vacuum, water can be drawn up in a column _______ feet - Correct
Answers -33.9
which of the following is considered to be a chemical contaminant? - Correct Answers -
arsenic
which of the following is considered to be a biological health hazard - Correct Answers -
giardia
what type of assembly has two internally spring loaded check, two shut-off valves, and
four test cocks? - Correct Answers -double check valve
air gap is the_________ when directly connecting potable water supply lines to
sewerage systems or to radioactive sources? - Correct Answers -most suitable
protection
a bypass of a backflow prevention assemble may be permitted only if the assembly in
the bypass: - Correct Answers -is the same type
what federal law made water purveyors responsible for water quality all the way into
consumers' homes or businesses? - Correct Answers -safe drinking water act
amendment of 1986
if a column of water is exerting a pressure of 50 psi, how high must the water be inside
the column? - Correct Answers -115.5
as the velocity of water increases, pressure: - Correct Answers -decreases
atmospheric pressure at sea level is _______ psi - Correct Answers -14.7
, a water supply other than the water purveyor's approved supply, that is on or available
to the premises is called a - Correct Answers -auxiliary water supply
how can a backsiphonage action be broken - Correct Answers -air gap
what single difficult to regulate item is most commonly associated with cross
connections, specifically through backsiphonage? - Correct Answers -garden house
the appropriate height fo an air gap is - Correct Answers -twice the diameter of the pipe
above the flood rim of vessel, minimum of 1 inch
while testing check balbe #1 on a DC, water recedes from the tuve attached to test cock
#3. The gauge should be moved to the centerline of the assembly and the static
pressure drop across the no. 1 check should be recorded. What other information
should be recorded. - Correct Answers -check valve #2 is leaking and shutoff valve #2
is leaking
at what point is the relief valve in an RP required to open - Correct Answers -2.0 psid
what is the minimum spring tension recommended on the #1 check valve in an RPZ -
Correct Answers -3 psi greater than the tension on the relief valve.
according to the USC, what is the correct height for installing an RPZ - Correct Answers
-12 inches above grade, but no more than 36 inches
what is the correct height to install a PVB - Correct Answers -12 inches above the
highest downstream point.
what company or agency is responsible for testing and approving all backflow
prevention assemblies in the united states? - Correct Answers -foundation of cross-
connection control & hydraulic research
backflow prevention assemblies are often installed in parallel in order to: - Correct
Answers -maintain service during testing and repairs
which of the following is not a criterion for an approved assembly? - Correct Answers -
shipped by manufacturer in separate parts for inspection
what is the minimum pressure drop across a spring-loaded, soft-seated check valve? -
Correct Answers -1.0 psid
according to usc, what is the correct height to install an atmospheric vacuum breaker? -
Correct Answers -6 inches above the highest downstream point
test kits should be verified for accuracy and, if needed, calibrated how often? - Correct
Answers -at least once a year
