Test Flashcards
Your water supplier may interrupt water service to a customer when
Provisions in the cross connection, control, ordinance, or regulations are not met
Backflow in a public water supply can be caused by
back pressure or backsiphonage
An atmospheric vacuum breaker may have a downstream shut off valve
Under no circumstances
The 1996 Federal safe drinking water act places, a primary responsibility for the quality of the public water supply on which of the following
Water purveyor
An airgap must have
Two times the pipe diameter with the minimum of 1 inch separation
An unprotected bypass around a reduced pressure principle backflow prevention assembly is
Not permissible
The major concern of the water purveyor where an auxiliary water supply is utilized or maintained is to ensure that
Backflow protection is provided at the water service connection
A pressure vacuum breaker may be installed with a
Shut off valve downstream
Two types of cross connections are
Direct and indirect
When nontoxic antifreeze chemicals are added to a fire suppression system, which of the following is required to protect the potable water supply
Reduced pressure principle backflow prevention assembly
Internal protection refers to
Backflow protection at each point of use
Lye is back siphoned from an open vat, without a cover over the top by a direct cross connection this constitutes a
Health hazard
In responding to a suspected backflow incident, the water purveyor should
Implement emergency response plan
The loading of the first and second check valves and reduced pressure principle backflow prevention assemblies are always
Different
Undersized water, service, and distribution piping carrying water at high velocity
May cause back siphonage due to aspirator effect
A perfect vacuum at sea level will raise water in a pipe a maximum of
33.9 feet
The water supplier may require more frequent field testing of backflow prevention assemblies due to
High incident of field test failures of the assembly
A differential pressure gauge is used to field test
Reduced pressure principle backflow assemblies
The relief valve opening point of a reduced pressure principle backflow prevention assembly must open at or above
2.0 PSID
When field testing a reduced pressure principle backflow prevention assembly, the number two testcock should be flushed
With caution to prevent premature opening of relief valve
During a field test, the air inlet valve on a pressure vacuum breaker must open at or
Above 1.0 PSID
Hose bib vacuum breakers should be located
On hose bibs as required by code
The probable cause of an intermittent discharge of the relief valve on a reduced pressure principle backflow prevention assembly is
Fluctuations and supply line pressure
When entering a vault containing a backflow prevention assembly does tester should
Check quality of the atmosphere prior to entry
A service or containment protection, backflow prevention assembly is meant to protect
Public water supply system
A vacuum breaker is used to protect against
Back siphonage
A tester required to report backflow prevention field test information to the
Administrative authority
Backflow prevention assembly shall be field tested
When required by local administrative authority
Backflow prevention assemblies should be repaired
When field test results indicate failure
Check valves of double check valve backflow prevention assemblies must be
Internally loaded
A vacuum relief valve should be installed
Never as a backflow prevention assembly
When repairing double check valve assemblies the tester should not
Modify internal components
A backflow prevention assembly should make an abnormal humming noise during operation under which of the following conditions
Never
The accuracy of fuel test gauges should be checked
At least annually
The air gap drain funnel for the relief valve of a reduced pressure principle backflow prevention assembly
May not be sufficient to handle the full relief valve discharge
How many tests are there on a pressure vacuum breaker
Two
An atmospheric vacuum breaker must be installed
6 inches above highest outlet and all downstream piping
A double check valve assembly is field tested with a
Differential gauge
The type of backflows are
Back pressure and back siphonage conditions
A Watermain break will most likely cause what condition
Back siphonage
A reduced pressure principle backflow prevention assembly shall be installed
Readily accessible above grade
Which component of a pressure vacuum breaker must be field tested first
Air inlet valve
Each of the check valves in a double check valve assembly is designed to hold in the direction of flow a minimum static pressure of
1.0 psi
An absolute pressure of 25 PSIA at sea level is equal to approximately what value engage pressure PSIG
10 PSIG
Results of a field test on a backflow prevention assembly should not include, which of the following information on the report form
Date of manufacture
To properly field test, a reduced pressure principle backflow prevention assembly
The inlet shut off valve must be open
A pressure vacuum breaker may be used for backflow protection for which of the following conditions
Back siphonage health hazards
The relief valve of reduced pressure principle backflow prevention assembly discharges in a static, no flow condition and stops discharging during the flow condition. The most likely cause is.
Fouled check valve number one
A 2 inch atmospheric vacuum breaker when used on irrigation systems shall be installed at least _______ inches above the downstream piping outlets
Six
When field testing a double check valve assembly and check valve number one leaks the tester
May test check valve number two before repairing check valve number one
A backflow prevention assembly consisting of two independently operating internally loaded check valves located between two tightly closed shut off valves with four approximately located test cocks is a
Double check valve assembly
A reduced pressure principle backflow prevention assembly must be installed at least
12 inches above grade
Edible syrup in a cannery was forced into a drinking water line through a direct cross connection. This could’ve been prevented by the installation of a.
Double check valve assembly
To properly solve a cross connection, contamination incident a qualified person should
Identify an isolate, the source of contamination, the affected area, and notify customers and the health department and take water samples
To convert feet of head to pounds per square inch multiply by
0.4333
The physical operation of a hose bib vacuum breaker is classified as a type of
Atmospheric vacuum breaker
A contaminated auxiliary water supply is utilized to maintain high pressure of a fire sprinkler system to protect the potable water supply. What protection should be installed at the service connection.
Reduced pressure principle backflow prevention assembly
When restoring service to the customer after testing a double check valve assembly the shut off valves are opened
Slowly number one shut off valve first
It is possible to compensate for a leaking number to shut off valve during the field test of a reduced pressure principle backflow prevention assembly by attaching a temporary bypass hose from
Number one test cock, to number four test cock
When field testing a pressure vacuum breaker near a ceiling, the gauge should
Be placed at the same elevation as the assembly
Which of the following could create a closed water system if installed in the service supply line
Backflow prevention assembly
A total cross connection control program should be coordinated with
Plumbing inspector, local health department, water purveyor
The temperature increases in a closed plumbing system. This is an example of.
Thermal expansion
The maximum head loss across a double check valve from zero to rated flow is
10.0 psi
Which of the following conditions would not be a hazard to a public water supply?
A reduced pressure principle backflow prevention assembly installed on a cooling tower feed line that is tested twice a year
During the held test of a leaking check valve number two on a reduced pressure principle backflow prevention assembly pressure is bypassed through the gauge from test cock number two to test cock number four this procedure will
Cause the differential pressure reading to drop and cause the relief valve to open
During the field test of a check valve in a pressure vacuum breaker, the high bleed needle valve is left open this procedure will
Reduce the pressure between the check valve and the number one shut off valve
When field testing a double check valve assembly check valve number one is found to be leaking. The next step is to.
Test check valve number two
The differential pressure gauges used for field testing backflow prevention assemblies read in minimum increments of
.1 PSID
After the installation of a reduced pressure principle backflow prevention assembly, the number one shut off valve is turned on to establish water pressure within the assembly. Upon opening the number one shut off valve. The relief valve discharge is continuously this discharge may be an indication of.
A foul check valve number one
The spring and the relief valve of a reduced pressure principle backflow prevention assembly is designed to
Open the relief valve
During the test of a check valve on a pressure vacuum breaker water continues to flow from the test cock number two. This is an indication of.
Leaky number one shut off valve
Any pressure less than that exerted by the atmosphere is defined as a
Vacuum
Performance design specifications of reduced principle backflow prevention assemblies, require that the differential pressure check valve number 1 be ______ PSID greater than the opening point of the relief valve
3.0
How many tests are required on a reduced pressure principle backflow prevention assembly
Four
The relief valve of a reduced pressure, principle backflow prevention assembly discharges, continuously during both flow and no flow conditions. The most probable cause is.
Foul relief valve
To exert a pressure of one PSI at the base of a column of water, the column would have to be
27.75 inches high
