Water Distribution Practice Test
Questions with 100% Correct
Answers
What varies depending on the vehicle mass or weight, type of brakes, weather
conditions, road conditions, time of day, road incline, and drivers visual acuity and
reaction time - Answer-actual stopping distance
What record must be kept of TTC activities - Answer-starting and end times, location,
names of personnel, and TTC used
Name 4 typical TTC zones - Answer-advanced warning area, transition area, activity
area, and termination area
Where should SCBA be stored - Answer-relatively close, but not in the chlorine storage
area
What is the primary confined space hazard - Answer-oxygen deficient environment
What is considered an oxygen enriched atmosphere - Answer-oxygen above 21 percent
What toxic gas is sometimes odorless - Answer-carbon monoxide
What percentage of workers who die in confined spaces are would-be rescuers -
Answer-50 percent
Difference between primary and secondary standards - Answer-primary standards pose
a threat to human health; secondary standards do not
Type of motor used when infrequent starting is required and load needs to be brought
up to speed very quickly - Answer-capacitor start
Type of level sensor with air connected to a pressure transducer - Answer-diaphragm
element
First action that should be taken when a large main break occurs - Answer-locate the
valves that isolate the leak
How far in advance of work should a flagman be located - Answer-100 feet
,What should the top line of a portable message board provide - Answer-information on
the problem
Delivered min. working pressure - Answer-35 PSI
RP backflow preventer will stop... - Answer-back pressure and back siphon age
gate valves have less... - Answer-friction loss
cavitation is caused by... - Answer-excess pump speed
hydrant flow - Answer-(2.83)(D^2)(l)/(square root of H)=GPM
min. distribution pressure - Answer-20 PSI
aquifer - Answer-water bearing stratum of rock, sand, or gravel
type of rupture or breakage that may occur when a pipe is unevenly supported along its
length - Answer-beam breakage
AWWA's max distance between residential valves - Answer-800 ft.
min. flushing velocity when unidirectional flushing method - Answer-5 FPS
which type of level sensor requires an air supply - Answer-bubbler tube
MCL for chloride - Answer-250 mg/L
two tier 1 violations - Answer-acute risk to health
purpose for metallic tracer tape - Answer-locating protection of distribution pipe
min. backflow protection against a cross connection containing a contaminant that is
dangerous to health - Answer-double check valve assembly
reverse water flow caused by a vacuum is called... - Answer-back siphon age
min. contact time when disinfecting water mains with the chlorine slug method - Answer-
3 hours
DI pipe primarily used for river crossings and underwater intakes - Answer-ball and
socket
a reduced pressure zone device consists of two spring loaded check valves with a... -
Answer-pressure regulated relief located between them
, a venturi meter has... - Answer-two taps, the downstream tap is the high pressure tap
anodes suspended in a tank are used to prevent... - Answer-corrosion
min height of well vent pipe - Answer-36 inches
test that determines if mains need cleaning or replacement - Answer-fire flow test
water demand in a community is usually estimated on the basis of - Answer-per capita
demand
valves needed at pipe crosses - Answer-three
valves needed at pipe tees - Answer-two
min acceptable CL2 residual when using chloramines for disinfection - Answer-.6 mg/L
CL2 residual needed to disinfect well casings - Answer-50 ml/L
backflows are installed downstream from the what - Answer-meter
double check backflows offer what level of protection - Answer-least
RP backflows offer what level of protection - Answer-medium
RP backflows have what between two check valves - Answer-relief valve
what offers the highest level of backflow protection - Answer-air gap
min and max distance backflows to be off ground - Answer-12 min 30 inches max
what is a more powerful disinfectant than chloramines - Answer-chlorine
what disinfectant is more persistent than chlorine - Answer-chloramines
chloramines are more effective than chlorine against what - Answer-biofilms
main chlorination at 25-50 mg/L is held for how long - Answer-24 hours
min CL2 residual for main after 24 hour hold - Answer-10 mg/L
main slug method at 100 mg/l must be held for min of - Answer-3 hours
calcium hypochlorite can support a fire when stored close to what - Answer-organics
Questions with 100% Correct
Answers
What varies depending on the vehicle mass or weight, type of brakes, weather
conditions, road conditions, time of day, road incline, and drivers visual acuity and
reaction time - Answer-actual stopping distance
What record must be kept of TTC activities - Answer-starting and end times, location,
names of personnel, and TTC used
Name 4 typical TTC zones - Answer-advanced warning area, transition area, activity
area, and termination area
Where should SCBA be stored - Answer-relatively close, but not in the chlorine storage
area
What is the primary confined space hazard - Answer-oxygen deficient environment
What is considered an oxygen enriched atmosphere - Answer-oxygen above 21 percent
What toxic gas is sometimes odorless - Answer-carbon monoxide
What percentage of workers who die in confined spaces are would-be rescuers -
Answer-50 percent
Difference between primary and secondary standards - Answer-primary standards pose
a threat to human health; secondary standards do not
Type of motor used when infrequent starting is required and load needs to be brought
up to speed very quickly - Answer-capacitor start
Type of level sensor with air connected to a pressure transducer - Answer-diaphragm
element
First action that should be taken when a large main break occurs - Answer-locate the
valves that isolate the leak
How far in advance of work should a flagman be located - Answer-100 feet
,What should the top line of a portable message board provide - Answer-information on
the problem
Delivered min. working pressure - Answer-35 PSI
RP backflow preventer will stop... - Answer-back pressure and back siphon age
gate valves have less... - Answer-friction loss
cavitation is caused by... - Answer-excess pump speed
hydrant flow - Answer-(2.83)(D^2)(l)/(square root of H)=GPM
min. distribution pressure - Answer-20 PSI
aquifer - Answer-water bearing stratum of rock, sand, or gravel
type of rupture or breakage that may occur when a pipe is unevenly supported along its
length - Answer-beam breakage
AWWA's max distance between residential valves - Answer-800 ft.
min. flushing velocity when unidirectional flushing method - Answer-5 FPS
which type of level sensor requires an air supply - Answer-bubbler tube
MCL for chloride - Answer-250 mg/L
two tier 1 violations - Answer-acute risk to health
purpose for metallic tracer tape - Answer-locating protection of distribution pipe
min. backflow protection against a cross connection containing a contaminant that is
dangerous to health - Answer-double check valve assembly
reverse water flow caused by a vacuum is called... - Answer-back siphon age
min. contact time when disinfecting water mains with the chlorine slug method - Answer-
3 hours
DI pipe primarily used for river crossings and underwater intakes - Answer-ball and
socket
a reduced pressure zone device consists of two spring loaded check valves with a... -
Answer-pressure regulated relief located between them
, a venturi meter has... - Answer-two taps, the downstream tap is the high pressure tap
anodes suspended in a tank are used to prevent... - Answer-corrosion
min height of well vent pipe - Answer-36 inches
test that determines if mains need cleaning or replacement - Answer-fire flow test
water demand in a community is usually estimated on the basis of - Answer-per capita
demand
valves needed at pipe crosses - Answer-three
valves needed at pipe tees - Answer-two
min acceptable CL2 residual when using chloramines for disinfection - Answer-.6 mg/L
CL2 residual needed to disinfect well casings - Answer-50 ml/L
backflows are installed downstream from the what - Answer-meter
double check backflows offer what level of protection - Answer-least
RP backflows offer what level of protection - Answer-medium
RP backflows have what between two check valves - Answer-relief valve
what offers the highest level of backflow protection - Answer-air gap
min and max distance backflows to be off ground - Answer-12 min 30 inches max
what is a more powerful disinfectant than chloramines - Answer-chlorine
what disinfectant is more persistent than chlorine - Answer-chloramines
chloramines are more effective than chlorine against what - Answer-biofilms
main chlorination at 25-50 mg/L is held for how long - Answer-24 hours
min CL2 residual for main after 24 hour hold - Answer-10 mg/L
main slug method at 100 mg/l must be held for min of - Answer-3 hours
calcium hypochlorite can support a fire when stored close to what - Answer-organics
