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Pool Operator Exam With Correct Detailed
Answers 2025/2026 latest Update.
whole range chlorine in a pool: ____ to _____ - ANSWER- 1, 5 ideal range chlorine in a pool: ____ to _____ - ANSWER- 2, 4 whole range chlorine in a spa: ____ to _____ - ANSWER- 2, 10 ideal range chlorine in a spa: ____ to _____ - ANSWER- 3, 5 4 types of solid chlorine - ANSWER- calcium hypochlorite, lithium hypochlorite, trichlor, dichlor liquid chlorine - ANSWER- sodium hypochlorite (NaOCl) how active is gas chlorine - ANSWER- 100% the active killing form of chlorine in water - ANSWER- hypochlorous acid (HOCl) HOCl = ______ - ANSWER- H+ (hydrogen ion) + OCl- (hypochlorite ion) most common granular chlorine (pH range) - ANSWER- calcium hypochlorite (8.5 - 11, used to super chlorinate water) not common form of chlorine due to low active strength (pH) - ANSWER- lithium hypochlorite (10.8) tablet/stick chlorine usually used in erosion feeder (pH - what will it do?) - ANSWER- trichlor (2.8 - 3.5, lower alkalinity and pH over time) salt used as a disinfectant (pH) - ANSWER- dichlor (6.7 - common in vinyl lined pools) most common type of chlorine used (pH) - ANSWER- sodium hypochlorite (NaOCl - 13) ______ needs special training to use and has a pH of ____ and will _____ when added to water - ANSWER- gas chlorine, 0, lower pH chlorine is most effective as a pH of _____ - ANSWER- 7. active disinfectant in the water - ANSWER- free chlorine (FC)
FC is determined by the ______ test and is maintained between ____ and ____ ppm - ANSWER- DPD, 2, 4 equal to the amount of hypochlorous acid (HOCl) and the amt of hypochlorite ions (OCl- ) - ANSWER- free chlorine (fc) the result of free chlorine reacting with organic compounds - ANSWER- combine chlorine (CC) common name and max for pools and spas for combine chlorine - ANSWER- chloramines, 0.2, 0. CC = - ANSWER- TC - FC what will a DPD measure - ANSWER- TC, FC how much CC should a pool have ideally - ANSWER- zero shocking the pool is also called - ANSWER- breakpoint chlorination breakpoint chlorination is the conversion of ________ into ______ - ANSWER- combine chlorine, nitrogen gas breakpoint chlorination equation - ANSWER- BPC = 10 x CC [BPC = 10 x (TC - FC)] whole cyanuric acid range: _____ to ______ppm - ANSWER- 0, 100 ideal cyanuric acid range: _____ to ______ ppm - ANSWER- 30, 50 acts as a protection for chlorine compounds from UV light - ANSWER- cyanuric acid CyA will act as a stabilizer for _______ but does not stabilize ________ - ANSWER- free chlorine, bromine The only way to reduce CyA concentration is to _______ - ANSWER- dilute the water and replace it whole range of bromine: ____ to _____ - ANSWER- 2, 10 ideal range of bromine: _____ to ______ - ANSWER- 4, 6 second most common disinfectant in the pool - ANSWER- bromine two types of bromine used - ANSWER- sodium bromide, solid bromide Bromine in natural form is a ______ but is in _____ form when
how much sodium bicarbonate should be added to increase total alkalinity? - ANSWER- 1.4 pounds per 10000 gal of water high total alkalinity leads to (4) - ANSWER- pH lock, cloudy waters, clogged filters, reduced circulation if you have high total alkalinity, add _____ or ______ - ANSWER- muriatic acid, sodium bisulfate whole range for calcium hardness in a pool: ____ to ____ - ANSWER- 150, 1000 ideal range of calcium hardness in a pool: ____ to ____ - ANSWER- 200, 400 whole range of calcium hardness in a spa: ____ to ____ - ANSWER- 100, 800 ideal range of calcium hardness in a spa: ____ to ____ - ANSWER- 150, 250 amount of calcium content in the water - ANSWER- calcium hardness calcium hardness is measured as ______ - ANSWER- calcium carbonate (CaCO3) calcium not in solution (as a solid) is called _____ - ANSWER- scale calcium hardness is affected by _______ - ANSWER- temperature when temp rises, calcium hardness becomes ______ - ANSWER- less soluble low calcium hardness leads to (3) - ANSWER- corrosive water, wall stains, heater failure if you have low calcium hardness, add - ANSWER- calcium chloride high calcium hardness leads to (3) - ANSWER- scale, cloudy water, clogged filters the only way to lower calcium hardness is to _____ - ANSWER- partially drain the water and replace it max temperature of a pool or spa - ANSWER- 104 degrees at higher temps, there is an increased tendency for _____ - ANSWER- scaling at lower temperatures, there is an increased tendency for ______ - ANSWER- corrosion maximum total disolved solids - ANSWER- 1500 saturation index equation: SI= - ANSWER- pH + TF + CF + AF + TDSF
green water - ANSWER- presence of copper red-brown water - ANSWER- presence of iron number one reason for cloudy water - ANSWER- improper filtration too much calcium in the water leads to - ANSWER- scale cause of foaming - ANSWER- organic waste three types of algae - ANSWER- green, black, yellow most common and most easily controlled algae - ANSWER- green algae resulting from poor pool circulation - ANSWER- black algae that is difficult to control and often requires_____ - ANSWER- yellow, algaecide pool capacity (in gallons) is equal to the pool _______ times _______ - ANSWER- volume, 7.5 gallons minerals that cause stains (3) - ANSWER- iron, copper, manganese chemicals used to neutralize chlorine (2) - ANSWER- sodium thiosulfate, sodium sulfite acceptable range of free chlorine in a pool: ____ to ____ppm - ANSWER- 1, 3 ideal chlorine in a spa - ANSWER- 4 what causes the chlorine smell in an indoor pool - ANSWER- chloramines evaporating what are caused by chlorine combining itself to organic maters (like ammonia)? - ANSWER- chloramines which chlorine has a pH of nine and raises the pH of water? - ANSWER- liquid chlorine _____ deteriorates quickly into exposed air - ANSWER- sodium hypochlorite When using CA to stabilize a pool the chlorine level must stay above _____ ppm - ANSWER- 2 how is bromine different from chlorine? - ANSWER- combine bromine can be used as an effective sanitizer
the more particles and dirt that a filter removes, the slower the _____ - ANSWER- flow rate removes the smallest particle size of any pool spa filtration device - ANSWER- diatomaceous Earth filter (DE) what occurs over time in a sand filter - ANSWER- channeling channeling in a filter causes - ANSWER- a bypass in the filtration process, causing unfiltered water back into the pool when the water in the pipe is ______ then backwash is complete - ANSWER- clear As dirt and debris collect in a sand filter the ______ pressure increases and the _______ pressure decreases - ANSWER- influent, effluent are cartridge filters backwashed? - ANSWER- no (removed and hosed off) are sand filters backwashed? - ANSWER- yes depth markers should be at - ANSWER- horisontal surfaces, vertical surfaces, and twenty feet apart each electrical system must have ________ - ANSWER- ground fault circuit interrupters (GFIs) who is responsible for taking daily logs? - ANSWER- pool operator
