1|Page
CPO Certified Pool Operator Practice Examination,
Pool & Hot Tub Alliance (PHTA) ||Verified Exam!!||
National Swimming Pool Foundation (NSPF),
2026/2027 –Questions with Complete Q&A and Verified
Answers||Newest Exam!!!
7. You are the operator of a 330,000 gallon outdoor pool.
Your local health department requires you to perform a
water balance calculation once monthly. Upon performing
the water tests necessary to perform this calculation, you
observe the following readings in your pool: Total alkalinity
is 50 ppm pH is 7.2 Calcium Hardness is 150 ppm
Temperature is 76 degrees F Total Dissolved Solids is 500
ppm Using these readings, what is the Saturation Index for
this pool? - Answer--0.8
8. To adjust the tested Total Alkalinity in the pool in
question #7 to an acceptable level, which chemical would
be most appropriate? - Answer-Sodium Bicarbonate
9. To adjust the tested pH in the pool in question #7 to an
acceptable level, which chemical would be most
appropriate? - Answer-Sodium Carbonate
,2|Page
10. You are the CPO for a 28,000 gallon hotel pool. You
perform a water balance chemical test, and to your
surprise, the Calcium Hardness is only 100 ppm. How
much calcium chloride (77%) would be required to
increase this to 400 ppm?" - Answer-100.8 lbs.
11. You are the CPO for a 100 foot long, 50 foot wide
country club pool. The average depth of this pool is 7 feet.
You return to the pool on Monday morning, after a rare
weekend off, and find that the auto-fill feature has failed to
work, and the pool water level is four inches too low. How
many gallons of water must be added to return the water
to the proper level? - Answer-12,495 gallons
12. You are the operator of a 3,000 gallon health club spa,
which has an average of 100 users per day. According to
the CPO Handbook, how often should the water in this spa
be changed? - Answer-10 days
"13. You are the CPO for a large municipal swimming pool.
This pool has a volume of 560,000 gallons of water,and
has an average daily bather load of 1300 people. The pool
is operated using high rate pressure sand filters. How
often should you backwash the filters?" - Answer-When
the influent and effluent gauges are 10 to 20 psi apart
, 3|Page
14. In testing for Chlorine/Bromine in a commercial pool,
DPD is preferred over OTO because: - Answer-OTO only
tests for Total Chlorine
15. Safety and rescue equipment should always be: -
Answer-Kept easily accessible around the pool
16. Which type of filter system will remove the smallest
micron particles? - Answer-diatomaceous earth
17. If the pump fails to prime, which of the following does
not have to be checked? - Answer-filter system pressure is
too high
18. Oxidation Reduction Potential testing (ORP) is
measured in? - Answer-mV
19. High calcium hardness can result in what condition? -
Answer-cloudy water
CPO Certified Pool Operator Practice Examination,
Pool & Hot Tub Alliance (PHTA) ||Verified Exam!!||
National Swimming Pool Foundation (NSPF),
2026/2027 –Questions with Complete Q&A and Verified
Answers||Newest Exam!!!
7. You are the operator of a 330,000 gallon outdoor pool.
Your local health department requires you to perform a
water balance calculation once monthly. Upon performing
the water tests necessary to perform this calculation, you
observe the following readings in your pool: Total alkalinity
is 50 ppm pH is 7.2 Calcium Hardness is 150 ppm
Temperature is 76 degrees F Total Dissolved Solids is 500
ppm Using these readings, what is the Saturation Index for
this pool? - Answer--0.8
8. To adjust the tested Total Alkalinity in the pool in
question #7 to an acceptable level, which chemical would
be most appropriate? - Answer-Sodium Bicarbonate
9. To adjust the tested pH in the pool in question #7 to an
acceptable level, which chemical would be most
appropriate? - Answer-Sodium Carbonate
,2|Page
10. You are the CPO for a 28,000 gallon hotel pool. You
perform a water balance chemical test, and to your
surprise, the Calcium Hardness is only 100 ppm. How
much calcium chloride (77%) would be required to
increase this to 400 ppm?" - Answer-100.8 lbs.
11. You are the CPO for a 100 foot long, 50 foot wide
country club pool. The average depth of this pool is 7 feet.
You return to the pool on Monday morning, after a rare
weekend off, and find that the auto-fill feature has failed to
work, and the pool water level is four inches too low. How
many gallons of water must be added to return the water
to the proper level? - Answer-12,495 gallons
12. You are the operator of a 3,000 gallon health club spa,
which has an average of 100 users per day. According to
the CPO Handbook, how often should the water in this spa
be changed? - Answer-10 days
"13. You are the CPO for a large municipal swimming pool.
This pool has a volume of 560,000 gallons of water,and
has an average daily bather load of 1300 people. The pool
is operated using high rate pressure sand filters. How
often should you backwash the filters?" - Answer-When
the influent and effluent gauges are 10 to 20 psi apart
, 3|Page
14. In testing for Chlorine/Bromine in a commercial pool,
DPD is preferred over OTO because: - Answer-OTO only
tests for Total Chlorine
15. Safety and rescue equipment should always be: -
Answer-Kept easily accessible around the pool
16. Which type of filter system will remove the smallest
micron particles? - Answer-diatomaceous earth
17. If the pump fails to prime, which of the following does
not have to be checked? - Answer-filter system pressure is
too high
18. Oxidation Reduction Potential testing (ORP) is
measured in? - Answer-mV
19. High calcium hardness can result in what condition? -
Answer-cloudy water
