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CERTIFIED POOL OPERATOR HANDBOOK
PRACTICE TEST 2025 QUESTIONS AND
ANSWERS.
1. You operate a 120,000-gallon pool, and upon performing your hourly chemical
tests you observe the following readings: Total Available Chlorine reading is 1.6
free available chlorine reading is 1.5 pH is 7.4 Your supervising lifeguard has just
informed you that you have had a fecal incident occur; a solid stool has been
discharged into the pool. According to the Centers for Disease Control, as the
CPO, you should do the following: -correct answer-clear the pool and raise the free
chlorine to 2 ppm
2. Assuming that your local health department requires you to raise the free
chlorine to 5 ppm, how much sodium hypochlorite would be needed to raise the
free chlorine in the pool in question #1 to that level? -correct answer-3.5 gallons
3. You are the CPO for an indoor health club pool. The facility manager informs
you that he is receiving complaints about a strong chlorine odor in the pool area,
and several members have complained of eye irritation. The most likely cause of
these complaints is: -correct answer-high levels of chloramines in the pool
4. To determine the level of chloramines in the water, you should do which of the
following? -correct answer-test for total chlorine and free chlorine, then subtract
the free chlorine number from the total chlorine
5. You operate a 45,000 gallon indoor pool, and upon doing your hourly chemical
tests you observe the following readings:Total available chlorine is 2.2 Free
available chlorine is 1.4 and pH is 7.6 What is the level of chloramines in this
pool? -correct answer-0.8
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
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ppm Using these readings, what is the Saturation Index for this pool? -correct
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? -correct 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? -correct answer-Sodium Carbonate
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?" -
correct 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? -correct 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? -correct 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?" -correct answer-When the influent and effluent
gauges are 10 to 20 psi apart
14. In testing for Chlorine/Bromine in a commercial pool, DPD is preferred over
OTO because: -correct answer-OTO only tests for Total Chlorine
15. Safety and rescue equipment should always be: -correct answer-Kept easily
accessible around the pool
CERTIFIED POOL OPERATOR HANDBOOK
PRACTICE TEST 2025 QUESTIONS AND
ANSWERS.
1. You operate a 120,000-gallon pool, and upon performing your hourly chemical
tests you observe the following readings: Total Available Chlorine reading is 1.6
free available chlorine reading is 1.5 pH is 7.4 Your supervising lifeguard has just
informed you that you have had a fecal incident occur; a solid stool has been
discharged into the pool. According to the Centers for Disease Control, as the
CPO, you should do the following: -correct answer-clear the pool and raise the free
chlorine to 2 ppm
2. Assuming that your local health department requires you to raise the free
chlorine to 5 ppm, how much sodium hypochlorite would be needed to raise the
free chlorine in the pool in question #1 to that level? -correct answer-3.5 gallons
3. You are the CPO for an indoor health club pool. The facility manager informs
you that he is receiving complaints about a strong chlorine odor in the pool area,
and several members have complained of eye irritation. The most likely cause of
these complaints is: -correct answer-high levels of chloramines in the pool
4. To determine the level of chloramines in the water, you should do which of the
following? -correct answer-test for total chlorine and free chlorine, then subtract
the free chlorine number from the total chlorine
5. You operate a 45,000 gallon indoor pool, and upon doing your hourly chemical
tests you observe the following readings:Total available chlorine is 2.2 Free
available chlorine is 1.4 and pH is 7.6 What is the level of chloramines in this
pool? -correct answer-0.8
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
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ppm Using these readings, what is the Saturation Index for this pool? -correct
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? -correct 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? -correct answer-Sodium Carbonate
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?" -
correct 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? -correct 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? -correct 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?" -correct answer-When the influent and effluent
gauges are 10 to 20 psi apart
14. In testing for Chlorine/Bromine in a commercial pool, DPD is preferred over
OTO because: -correct answer-OTO only tests for Total Chlorine
15. Safety and rescue equipment should always be: -correct answer-Kept easily
accessible around the pool
