DISTRIBUTION PRACTICE EXAM GRADE 1 & 2
CERTIFICATION ARIZONA
1. What event does a continuous positive pressure in a distribution system
prevent?
Answer a backflow condition
2. Define the term "Backsiphonage"?
Answer a form of backflow due to a reduction in system pressure which causes a subsatmospheric pressure to exist at
the site in the water system
3. Reverse water flow in a distribution system caused by a vacuum in a water supply
main is called
Answer backsiphonage
4. Why must the relief port of a reduced pressure principle backflow prevention device
never be plugged or extended?
Answer so the device will function as designed
5. In instances where non-potable water or toxic wastes are connected directly with
,potable water systems, the preferred method of correction for such a cross connection is
byAnswer installing a physical separation (air gap) between the two systems
6. A connection between a safe and an unsafe water supply is called a
Answer cross connection
7. Why is it important to thoroughly flush out a newly installed backflow-preven- tion
device before testing?
Answer to rid the unit of foreign objects and particles
8. How must a pressure vacuum breaker backflow device be installed?
Answer it must be at least 12 inches above the highest downstream outlet
9. Name the condition in which the pressure in a distribution system is less than the
atmospheric pressure
Answer backsiphonage
10. What does a backsiphonage condition usually cause?
Answer reduced pressure or negative pressure on the service or supply side
11. On what item might you find a vacuum breaker?
Answer an irrigation system
,12. What does a double check valve backflow assembly provide effective protec- tion
from?
Answer both backpressure and backsiphonage of pollution
13. What is the maximum time period between having a backflow device tested by a
certified tester?
Answer 1 year
14. Which of the following has the greatest potential to cause contamination if a
cross connection occurs?
Answer a pesticide mixing tank
15. Which statement best describes the operation of a reduced pressure princi- pal
backflow assembly?
Answer the relief valve pressure principal backflow assembly
16. Which statement is true about a double check valve backflow assembly?
Answer a double check valve is not designed to stop backsiphonage of a health hazard
, 17. Who is responsible for insuring that water contamination due to a cross
connection does not occur?
Answer the public water system that is attected by cross connection
18. In general, which of the following groups of materials could best be de- scribed
as 'organic compounds'?
Answer TCE, PCE, and TCA
19. The hydrolysis of chlorine results in the formation of which two main chem- ical
species?
Answer hypochlorus acid and hydrochloric acid
20. What are the two main chemical species formed by chlorine in water and what
name are they known for collectively?
Answer HOCl and OCl-; free available chlorine
21. What is an aqueous solution of hydrogen chloride called?
Answer hydrochloric acid
22. When chlorine comes in contact with an organic material what carcinogenic
CERTIFICATION ARIZONA
1. What event does a continuous positive pressure in a distribution system
prevent?
Answer a backflow condition
2. Define the term "Backsiphonage"?
Answer a form of backflow due to a reduction in system pressure which causes a subsatmospheric pressure to exist at
the site in the water system
3. Reverse water flow in a distribution system caused by a vacuum in a water supply
main is called
Answer backsiphonage
4. Why must the relief port of a reduced pressure principle backflow prevention device
never be plugged or extended?
Answer so the device will function as designed
5. In instances where non-potable water or toxic wastes are connected directly with
,potable water systems, the preferred method of correction for such a cross connection is
byAnswer installing a physical separation (air gap) between the two systems
6. A connection between a safe and an unsafe water supply is called a
Answer cross connection
7. Why is it important to thoroughly flush out a newly installed backflow-preven- tion
device before testing?
Answer to rid the unit of foreign objects and particles
8. How must a pressure vacuum breaker backflow device be installed?
Answer it must be at least 12 inches above the highest downstream outlet
9. Name the condition in which the pressure in a distribution system is less than the
atmospheric pressure
Answer backsiphonage
10. What does a backsiphonage condition usually cause?
Answer reduced pressure or negative pressure on the service or supply side
11. On what item might you find a vacuum breaker?
Answer an irrigation system
,12. What does a double check valve backflow assembly provide effective protec- tion
from?
Answer both backpressure and backsiphonage of pollution
13. What is the maximum time period between having a backflow device tested by a
certified tester?
Answer 1 year
14. Which of the following has the greatest potential to cause contamination if a
cross connection occurs?
Answer a pesticide mixing tank
15. Which statement best describes the operation of a reduced pressure princi- pal
backflow assembly?
Answer the relief valve pressure principal backflow assembly
16. Which statement is true about a double check valve backflow assembly?
Answer a double check valve is not designed to stop backsiphonage of a health hazard
, 17. Who is responsible for insuring that water contamination due to a cross
connection does not occur?
Answer the public water system that is attected by cross connection
18. In general, which of the following groups of materials could best be de- scribed
as 'organic compounds'?
Answer TCE, PCE, and TCA
19. The hydrolysis of chlorine results in the formation of which two main chem- ical
species?
Answer hypochlorus acid and hydrochloric acid
20. What are the two main chemical species formed by chlorine in water and what
name are they known for collectively?
Answer HOCl and OCl-; free available chlorine
21. What is an aqueous solution of hydrogen chloride called?
Answer hydrochloric acid
22. When chlorine comes in contact with an organic material what carcinogenic
