Distribution Operator Certification Exams Study Guide
Study online at https://quizlet.com/_fcelwq
1. The size of water mains, pumping stations, and stor- fire protection require-
age tanks is primarily determined by: ments
2. Which of the following is a measure of the smoothness c value
of a pipe?
3. Why is excessive water pressure to residential homes decreases the life of wa-
objectionable? ter heaters and other wa-
ter-using appliances
4. What is the best time to perform a flushing program late at night to lessen traf-
on the mains? fic disruption and mini-
mize customer complaints
5. What type of ductile-iron pipe joint is used primarily ball-and-socket
for river crossings and underwater intakes, and occa-
sionally in rough terrain?
6. In general, a trench should be no more than how 1 to 2 ft
many feet wider than the diameter of the pipe?
7. Which of the following is a distribution layout pattern? grid
8. The utility's annual average day demand is deter- total water use for a year
mined by dividing the: by 365 days
9. Complaints of poor water quality will most likely occur tree
in which type of water main layout?
10. A main break may cause loss of pressure in the distri- contamination of the sys-
bution system, which in turn may result in: tem by backsiphonage
11. Vacuum breakers are designed to be used on piping backpressure will not exist
connections where:
, Distribution Operator Certification Exams Study Guide
Study online at https://quizlet.com/_fcelwq
12. What is the recommended minimum water pressure 20 psi
in a distribution system at any time, including fire flow
conditions?
13. Which of the following will least likely increase soil low soil moisture content
corrosiveness?
14. Push joints should not be used if the following condi- the pipe must be pushed
tion exists: on at an angle
15. An arterial-loop distribution system has flow from 4
how many directions?
16. As the temperature of the water increases, the disin- more effective
fecting action of chlorine is:
17. Large full storage tanks are typically disinfected with 10 mg/L
a chlorine residual of:
18. Why is a well acidified? increase the well's pro-
ductivity
19. What is the primary source of coliforms in a water fecal material from
supply? warm-blooded animals
20. pH is a measure of: hydrogen ions
21. What is the recommended contact time when disin- 3 hours
fecting water mains with the chlorine slug method?
22. Which of the following best defines the term static water level in a well when
water level? the well is not in operation
23.
, Distribution Operator Certification Exams Study Guide
Study online at https://quizlet.com/_fcelwq
Where are the chlorine samples typically collected at points representative of
from in the distribution system? conditions within the sys-
tem
24. Which of the following best defines the cone of de- depression around the
pression? well of the water sur-
face caused by pumping
waster from the well
25. Turbidity is caused by: suspended particles
26. What is the term for water samples collected at regu- time composite samples
lar intervals and combined in equal volume with each
other?
27. What chemical is present in a bacteria sample bottle sodium thiosulfate
for the purpose of neutralizing chlorine?
28. Chlorine neutralization is necessary when a treated bacteria
water sample is to be analyzed for:
29. The residual drawdown of a well is defined as: water level below the nor-
mal level that persists after
a well pump has been off
for a period of time
30. What is the basis for the number of samples that must population
be collected for utilities monitoring for lead and cop-
per that are in compliance or have installed corrosion
control?
31. Where should bacteriological samples be collected in at locations that are rep-
the distribution system? resentative of conditions
within the system
Study online at https://quizlet.com/_fcelwq
1. The size of water mains, pumping stations, and stor- fire protection require-
age tanks is primarily determined by: ments
2. Which of the following is a measure of the smoothness c value
of a pipe?
3. Why is excessive water pressure to residential homes decreases the life of wa-
objectionable? ter heaters and other wa-
ter-using appliances
4. What is the best time to perform a flushing program late at night to lessen traf-
on the mains? fic disruption and mini-
mize customer complaints
5. What type of ductile-iron pipe joint is used primarily ball-and-socket
for river crossings and underwater intakes, and occa-
sionally in rough terrain?
6. In general, a trench should be no more than how 1 to 2 ft
many feet wider than the diameter of the pipe?
7. Which of the following is a distribution layout pattern? grid
8. The utility's annual average day demand is deter- total water use for a year
mined by dividing the: by 365 days
9. Complaints of poor water quality will most likely occur tree
in which type of water main layout?
10. A main break may cause loss of pressure in the distri- contamination of the sys-
bution system, which in turn may result in: tem by backsiphonage
11. Vacuum breakers are designed to be used on piping backpressure will not exist
connections where:
, Distribution Operator Certification Exams Study Guide
Study online at https://quizlet.com/_fcelwq
12. What is the recommended minimum water pressure 20 psi
in a distribution system at any time, including fire flow
conditions?
13. Which of the following will least likely increase soil low soil moisture content
corrosiveness?
14. Push joints should not be used if the following condi- the pipe must be pushed
tion exists: on at an angle
15. An arterial-loop distribution system has flow from 4
how many directions?
16. As the temperature of the water increases, the disin- more effective
fecting action of chlorine is:
17. Large full storage tanks are typically disinfected with 10 mg/L
a chlorine residual of:
18. Why is a well acidified? increase the well's pro-
ductivity
19. What is the primary source of coliforms in a water fecal material from
supply? warm-blooded animals
20. pH is a measure of: hydrogen ions
21. What is the recommended contact time when disin- 3 hours
fecting water mains with the chlorine slug method?
22. Which of the following best defines the term static water level in a well when
water level? the well is not in operation
23.
, Distribution Operator Certification Exams Study Guide
Study online at https://quizlet.com/_fcelwq
Where are the chlorine samples typically collected at points representative of
from in the distribution system? conditions within the sys-
tem
24. Which of the following best defines the cone of de- depression around the
pression? well of the water sur-
face caused by pumping
waster from the well
25. Turbidity is caused by: suspended particles
26. What is the term for water samples collected at regu- time composite samples
lar intervals and combined in equal volume with each
other?
27. What chemical is present in a bacteria sample bottle sodium thiosulfate
for the purpose of neutralizing chlorine?
28. Chlorine neutralization is necessary when a treated bacteria
water sample is to be analyzed for:
29. The residual drawdown of a well is defined as: water level below the nor-
mal level that persists after
a well pump has been off
for a period of time
30. What is the basis for the number of samples that must population
be collected for utilities monitoring for lead and cop-
per that are in compliance or have installed corrosion
control?
31. Where should bacteriological samples be collected in at locations that are rep-
the distribution system? resentative of conditions
within the system
