Pool Operator Exam Question &
Answers ( Latest 2025 )
whole range chlorine in a pool: ____ to _____ - CORRECT
ANSWERS ✔✔1, 5
ideal range chlorine in a pool: ____ to _____ - CORRECT
ANSWERS ✔✔2, 4
whole range chlorine in a spa: ____ to _____ - CORRECT
ANSWERS ✔✔2, 10
ideal range chlorine in a spa: ____ to _____ - CORRECT
ANSWERS ✔✔3, 5
4 types of solid chlorine - CORRECT ANSWERS
✔✔calcium hypochlorite, lithium hypochlorite, trichlor,
dichlor
liquid chlorine - CORRECT ANSWERS ✔✔sodium
hypochlorite (NaOCl)
how active is gas chlorine - CORRECT ANSWERS
✔✔100%
,Pool Operator Exam Question &
Answers ( Latest 2025 )
the active killing form of chlorine in water - CORRECT
ANSWERS ✔✔hypochlorous acid (HOCl)
HOCl = ______ - CORRECT ANSWERS ✔✔H+
(hydrogen ion) + OCl- (hypochlorite ion)
most common granular chlorine (pH range) - CORRECT
ANSWERS ✔✔calcium hypochlorite (8.5 - 11, used to
super chlorinate water)
not common form of chlorine due to low active strength
(pH) - CORRECT ANSWERS ✔✔lithium hypochlorite
(10.8)
tablet/stick chlorine usually used in erosion feeder (pH -
what will it do?) - CORRECT ANSWERS ✔✔trichlor (2.8
- 3.5, lower alkalinity and pH over time)
salt used as a disinfectant (pH) - CORRECT ANSWERS
✔✔dichlor (6.7 - common in vinyl lined pools)
most common type of chlorine used (pH) - CORRECT
ANSWERS ✔✔sodium hypochlorite (NaOCl - 13)
, Pool Operator Exam Question &
Answers ( Latest 2025 )
______ needs special training to use and has a pH of ____
and will _____ when added to water - CORRECT
ANSWERS ✔✔gas chlorine, 0, lower pH
chlorine is most effective as a pH of _____ - CORRECT
ANSWERS ✔✔7.5
active disinfectant in the water - CORRECT ANSWERS
✔✔free chlorine (FC)
FC is determined by the ______ test and is maintained
between ____ and ____ ppm - CORRECT ANSWERS
✔✔DPD, 2, 4
equal to the amount of hypochlorous acid (HOCl) and the
amt of hypochlorite ions (OCl-) - CORRECT ANSWERS
✔✔free chlorine (fc)
the result of free chlorine reacting with organic
compounds - CORRECT ANSWERS ✔✔combine
chlorine (CC)
Answers ( Latest 2025 )
whole range chlorine in a pool: ____ to _____ - CORRECT
ANSWERS ✔✔1, 5
ideal range chlorine in a pool: ____ to _____ - CORRECT
ANSWERS ✔✔2, 4
whole range chlorine in a spa: ____ to _____ - CORRECT
ANSWERS ✔✔2, 10
ideal range chlorine in a spa: ____ to _____ - CORRECT
ANSWERS ✔✔3, 5
4 types of solid chlorine - CORRECT ANSWERS
✔✔calcium hypochlorite, lithium hypochlorite, trichlor,
dichlor
liquid chlorine - CORRECT ANSWERS ✔✔sodium
hypochlorite (NaOCl)
how active is gas chlorine - CORRECT ANSWERS
✔✔100%
,Pool Operator Exam Question &
Answers ( Latest 2025 )
the active killing form of chlorine in water - CORRECT
ANSWERS ✔✔hypochlorous acid (HOCl)
HOCl = ______ - CORRECT ANSWERS ✔✔H+
(hydrogen ion) + OCl- (hypochlorite ion)
most common granular chlorine (pH range) - CORRECT
ANSWERS ✔✔calcium hypochlorite (8.5 - 11, used to
super chlorinate water)
not common form of chlorine due to low active strength
(pH) - CORRECT ANSWERS ✔✔lithium hypochlorite
(10.8)
tablet/stick chlorine usually used in erosion feeder (pH -
what will it do?) - CORRECT ANSWERS ✔✔trichlor (2.8
- 3.5, lower alkalinity and pH over time)
salt used as a disinfectant (pH) - CORRECT ANSWERS
✔✔dichlor (6.7 - common in vinyl lined pools)
most common type of chlorine used (pH) - CORRECT
ANSWERS ✔✔sodium hypochlorite (NaOCl - 13)
, Pool Operator Exam Question &
Answers ( Latest 2025 )
______ needs special training to use and has a pH of ____
and will _____ when added to water - CORRECT
ANSWERS ✔✔gas chlorine, 0, lower pH
chlorine is most effective as a pH of _____ - CORRECT
ANSWERS ✔✔7.5
active disinfectant in the water - CORRECT ANSWERS
✔✔free chlorine (FC)
FC is determined by the ______ test and is maintained
between ____ and ____ ppm - CORRECT ANSWERS
✔✔DPD, 2, 4
equal to the amount of hypochlorous acid (HOCl) and the
amt of hypochlorite ions (OCl-) - CORRECT ANSWERS
✔✔free chlorine (fc)
the result of free chlorine reacting with organic
compounds - CORRECT ANSWERS ✔✔combine
chlorine (CC)
