CPO PRACTICE EXAM 50 QUESTIONS & CORRECT
ANSWERS LATEST 2025
Which type of filter requires the least amount of water to clean?
(A) Diatomaceous
(B) Rapid rate sand
(C) High rate sand
(D) Cartridge - ANSWER-(D) Cartridge
Cyanuric acid (stabilizer) protects free chlorine (FC) against the effects of:
(A) Pathogens like Crypto, Giardia, and Shigella
(B) High Total dissolved solids
(C) Ultraviolet rays from the sun
(D) High PH - ANSWER-(C) Ultraviolet rays from the sun
An erosion chemical feeder is what type of feeder?
(A) Peristaltic pump
(B) Piston pump
(C) Dry chemical feeder
(D) Gas system - ANSWER-(C) Dry chemical feeder
OSHA requires aquatic facilities to maintain:
(A) Safety Data Sheets only for sanitizing chemicals
,(B) Lifeguard certifications
(C) Air temperature recordings
(D) SDS's for all chemicals used at the facility - ANSWER-(D) SDS's for all chemicals
used at the facility
When mechanical cooling is used on an indoor therapeutic pool facility, the
recommended ASHRAE fresh air exchange rate should be:
(A) 2 to 4 exchanges per hour
(B) 4 to 6 exchanges per hour
(C) 6 to 8 exchanges per hour
(D) As many as possible - ANSWER-(B) 4 to 6 exchanges per hour
What condition mandates an immediate closure of your swimming pool?
(A) Locker room is not clean
(B) Main drain not visible from the deck
(C) No automatic feeders installed
(D) No underwater lights installed - ANSWER-(B) Main drain not visible from the
deck
The reagent commonly used to test PH is:
(A) DPD
(B) Sodium Thiosulfate
(C) Coolomatic
(D) Phenol red - ANSWER-(D) Phenol red
, When should you backwash high rate sand filters that have a single pressure
gauge?
(A) After an 8 to 10 psi increase above starting pressure
(B) Every 2 days
(C) Once per week
(D) When the influent and effluent gauges are 10 to 20 psi apart - ANSWER-(A)
After an 8 to 10 psi increase above starting pressure
Oxidation Reduction Potential testing (ORP) is measured in:
(A) Parts per million (ppm)
(B) Millivolts (mV)
(C) Gallons per minute (gpm)
(D) Free available chlorine (FAC) - ANSWER-(B) Millivolts (mV)
How much sodium thiosulfate would you need to lower the free chlorine from 18
ppm to 2.0 ppm in a 150,000 gallon pool?
(A) 35 lbs.
(B) 30 lbs.
(C) 25 lbs.
(D) 39 lbs. - ANSWER-(D) 39 lbs.
Evaporation heat losses from a pool are highest under which environmental
condition?
(A) High relative humidity
(B) Low relative humidity
(C) Clear sky
ANSWERS LATEST 2025
Which type of filter requires the least amount of water to clean?
(A) Diatomaceous
(B) Rapid rate sand
(C) High rate sand
(D) Cartridge - ANSWER-(D) Cartridge
Cyanuric acid (stabilizer) protects free chlorine (FC) against the effects of:
(A) Pathogens like Crypto, Giardia, and Shigella
(B) High Total dissolved solids
(C) Ultraviolet rays from the sun
(D) High PH - ANSWER-(C) Ultraviolet rays from the sun
An erosion chemical feeder is what type of feeder?
(A) Peristaltic pump
(B) Piston pump
(C) Dry chemical feeder
(D) Gas system - ANSWER-(C) Dry chemical feeder
OSHA requires aquatic facilities to maintain:
(A) Safety Data Sheets only for sanitizing chemicals
,(B) Lifeguard certifications
(C) Air temperature recordings
(D) SDS's for all chemicals used at the facility - ANSWER-(D) SDS's for all chemicals
used at the facility
When mechanical cooling is used on an indoor therapeutic pool facility, the
recommended ASHRAE fresh air exchange rate should be:
(A) 2 to 4 exchanges per hour
(B) 4 to 6 exchanges per hour
(C) 6 to 8 exchanges per hour
(D) As many as possible - ANSWER-(B) 4 to 6 exchanges per hour
What condition mandates an immediate closure of your swimming pool?
(A) Locker room is not clean
(B) Main drain not visible from the deck
(C) No automatic feeders installed
(D) No underwater lights installed - ANSWER-(B) Main drain not visible from the
deck
The reagent commonly used to test PH is:
(A) DPD
(B) Sodium Thiosulfate
(C) Coolomatic
(D) Phenol red - ANSWER-(D) Phenol red
, When should you backwash high rate sand filters that have a single pressure
gauge?
(A) After an 8 to 10 psi increase above starting pressure
(B) Every 2 days
(C) Once per week
(D) When the influent and effluent gauges are 10 to 20 psi apart - ANSWER-(A)
After an 8 to 10 psi increase above starting pressure
Oxidation Reduction Potential testing (ORP) is measured in:
(A) Parts per million (ppm)
(B) Millivolts (mV)
(C) Gallons per minute (gpm)
(D) Free available chlorine (FAC) - ANSWER-(B) Millivolts (mV)
How much sodium thiosulfate would you need to lower the free chlorine from 18
ppm to 2.0 ppm in a 150,000 gallon pool?
(A) 35 lbs.
(B) 30 lbs.
(C) 25 lbs.
(D) 39 lbs. - ANSWER-(D) 39 lbs.
Evaporation heat losses from a pool are highest under which environmental
condition?
(A) High relative humidity
(B) Low relative humidity
(C) Clear sky
