Backflow Flashcards
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Which devices can stop backsiphonage?
PVB, DCA, RP, and AVB
Which devices can stop back pressure?
DCA and RP
Which devices can handle constant pressure?
RP, DCA, and PVB
The approved backflow devices for non-health hazards include:
all devices (AVB,PVB,DCA, and RP)
Which device, or devices, are approved when there is chemical applied by aspiration, injection, or emission?
RP
If there is an on-site sewage facility, which back flow is approved?
RP
If major maintenance has to be performed, which back flow device has to be properly installed prior to the repair work being performed?
An approved backflow device
If including a master valve, where does it have to be installed?
Downstream from the PVB, DCA, or RP
Which devices have to be tested upon installation and annually?
Devices used in applications designated as health hazards
Which backflow devices have to be tested upon installation?
All backflow devices
If a DCA is installed below ground, what device is required?
A Y-strainer installed on inlet side of the DCA
If there is an additional water source supplying water to a system being supplied by a potable water supply, what device has to be used on with the potable water supply?
RP
What device cannot be used when there is a health hazard?
DCA
An AVB and PVB can be used in health hazard situations, if the following conditions are not present:
a) Backpressure
b) There is a pump downstream
c) Chemicals added
d) A pressure Regulator
e) A, B and C
e) A, B and C
An Atmospheric Vacuum Breaker:
a) Will stop backpressure
b) Has to be installed 6” higher than the highest head or outlet in the retracted position, will not handle constant pressure, and will stop backsiphonage
c) Has to be installed 12” higher than the highest head or outlet in the retracted position, will handle constant pressure, and will stop back siphonage
d) Has to be installed 6” higher than the highest head or outlet in the retracted position, will not handle constant pressure, and will not stop backpressure
e) A and B
E
What is the unwanted reversal of water flow in an irrigation system?
a) Backpressure
b) Contamination
c) Pollution
d) Backflow
d
A cross connection is any actual or potential connection between a potable water supply and:
a) A well
b) Any source that has the possibility to introduce polluted or contaminated water back into the potable water that is supplying it.
c) A drinking fountain
d) A pump station
b) Any source that has the possibility to introduce polluted or contaminated water back into the potable water that is supplying it.
Backsiphonage is caused by:
a) Negative or sub-atomospheric pressure
b) Greater pressure in the downstream side than the supply side
c) A pressure regulator
d) A pump downstream
a) negative or sub-atmospheric pressure
Backsiphonage can be caused by:
a) a break in the city main
b) A malfunctioning pressure regulator
c) The fire department using water from the city fire hydrant to put out fire
d) A & C
d) A & C
If the pressure in the sprinkler system (or downstream side) exceeds the pressure in the supply side, what phenomenon can occur?
a) Backpressure
b) Misting heads
c) Increased performance at the sprinkler heads
d) Backsiphonage
a) Backpressure
What can cause backpressure?
a) Gravity or a pump
b) Sub atmospheric pressure
c) A break in the city main
d) All of the above
a) Gravity or pump
How many total ways are there to protect against backpressure and/or backsiphonage?
a) 3
b) 6
c) 2
d) 5
d) 5
What is the unobstructed vertical distance through free atmosphere between the lowest point of a water supply outlet and the flood level rim of the fixture or assembly into which the outlet discharges?
a) Atmospheric vacuum breaker
b) Pressure vacuum breaker
c) A water gap
d) Reduced pressure principle device
e) An air gap
e) An air gap
The vertical, physical separations, of an air gap, must be:
a) at least twice the diameter of the water supply outlet, but never less than 3 inch.
b) at least three times the diameter of the water supply outlet, but never less than 1 inch.
c) at least twice the diameter of the water supply outlet, but never less than ½”
d) at least twice the diameter of the water supply outlet, but never less than 1 inch.
d) at least twice the diameter of the water supply outlet, but never less than 1 inch
What is a typical example of an air gap?
a) Pressure regulator
b) DCA
c) Kitchen sink
d) None of the above
c) Kitchen sink
What is the maximum number of hours an AVB can have constant pressure?
a) 2
b) 6
c) 12
d) 8
c) 12
How high does a pressure vacuum breaker have to be installed?
a) 6” above the highest head or outlet
b) 12” above the highest head or outlet
c) 12” above the grade
d) 12” above the highest head or outlet in the retracted position
d) 12” above the highest head or outlet in the retracted position
How many test cocks does a PVB, DCA, and RP have, respectively?
a) 4, 4 and 2
b) 1, 2 and 4
c) 2, 4 and 4
d) 4, 4 and 4
c) 2,4,4
If the highest head at the site is a shrub spray on a 12” riser, how high would a PVB have to be installed if right next to the head?
a) 6”
b) 18”
c) 12”
d) 24”
d) 24”
Which back flow devices incorporate two check valves?
a) DCA
b) RP
c) AVB
d) PVB
e) A and B
e) A and B
Which back flow device can be installed below grade (local regulation permitting)?
a) PVB
b) RP
c) AVB
d) DC
d) DC
How many test cocks are there on a DCA, RP, PVB and AVB respectively?
a) 4,4,2,0
b) 0,2,4,4
c) 4,4,4,4
d) 2,2,4,2
a) 4,4,2,0
Which back flow device uses a pressure differential relief valve and has to be installed 12” abover grade?
a) RP
b) DC
c) AVB
d) A and C
a) RP
There are two ball valves on which of the following?
a) DC
b) PVB
c) RP
d) A and C
d) A and C
The phenomenon that causes water to back flow due to elevation or a pump is called:
a) Backsiphonage
b) Backflow
c) Backpressure
d) Backflow device
c) Backpressure
