Pool Operator Final Exam 2025

Whole range chlorine in a pool: ____ to _____ - Correct Ans-1, 5 Ideal range chlorine in a pool: ____ to _____ - Correct Ans-2, 4 Whole range chlorine in a spa: ____ to _____ - Correct Ans-2, 10 Ideal range chlorine in a spa: ____ to _____ - Correct Ans-3, 5 4 types of solid chlorine - Correct Ans-calcium hypochlorite, lithium hypochlorite, trichlor, dichlor Liquid chlorine - Correct Ans-sodium hypochlorite (naocl) How active is gas chlorine - Correct Ans-100% The active killing form of chlorine in water - Correct Ans-hypochlorous acid (hocl) Hocl = ______ - Correct Ans-H+ (hydrogen ion) + ocl- (hypochlorite ion) Most common granular chlorine (ph range) - Correct Ans-calcium hypochlorite (8.5 - 11, used to super chlorinate water) Not common form of chlorine due to low active strength (ph) - Correct Ans-lithium hypochlorite (10.8) Tablet/stick chlorine usually used in erosion feeder (ph - what will it do?) - Correct Ans trichlor (2.8 - 3.5, lower alkalinity and ph over time) Salt used as a disinfectant (ph) - Correct Ans-dichlor (6.7 - common in vinyl lined pools) Most common type of chlorine used (ph) - Correct Ans-sodium hypochlorite (naocl - 13) ______ needs special training to use and has a ph of ____ and will _____ when added to water - Correct Ans-gas chlorine, 0, lower ph Chlorine is most effective as a ph of _____ - Correct Ans-7.5 Active disinfectant in the water - Correct Ans-free chlorine (FC) FC is determined by the ______ test and is maintained between ____ and ____ ppm - Correct Ans-DPD, 2, 4 Pool Pool Equal to the amount of hypochlorous acid (hocl) and the amt of hypochlorite ions (ocl-) - Correct Ans-free chlorine (fc) The result of free chlorine reacting with organic compounds - Correct Ans-combine chlorine (CC) Common name and max for pools and spas for combine chlorine - Correct Ans chloramines, 0.2, 0.5 CC = - Correct Ans-TC - FC What will a DPD measure - Correct Ans-TC, FC How much CC should a pool have ideally - Correct Ans-zero Shocking the pool is also called - Correct Ans-breakpoint chlorination Breakpoint chlorination is the conversion of ________ into ______ - Correct Ans combine chlorine, nitrogen gas Breakpoint chlorination equation - Correct Ans-BPC = 10 x CC [BPC = 10 x (TC - FC)] Whole cyanuric acid range: _____ to ______ppm - Correct Ans-0, 100 Ideal cyanuric acid range: _____ to ______ ppm - Correct Ans-30, 50 Acts as a protection for chlorine compounds from UV light - Correct Ans-cyanuric acid Cya will act as a stabilizer for _______ but does not Stabilize ________ - Correct Ans-free chlorine, bromine The only way to reduce cya concentration is to _______ - Correct Ans-dilute the water and replace it Whole range of bromine: ____ to _____ - Correct Ans-2, 10 Ideal range of bromine: _____ to ______ - Correct Ans-4, 6 Second most common disinfectant in the pool - Correct Ans-bromine Two types of bromine used - Correct Ans-sodium bromide, solid bromide Bromine in natural form is a ______ but is in _____ form when Added to pools - Correct Ans-reddish brown liquid, solid __________ is similar to hypochlorous acid - Correct Ans-hypobromous acid Pool Pool Bromine releases _____ and _____ when added to water - Correct Ans-hypobromite ion, hydrogen ion Bromine will ______ ph when added to water - Correct Ans-lower Whole range of ph: ____to_____ - Correct Ans-7.2, 7.8 Ideal range of ph: ____ to ____ - Correct Ans-7.4, 7.6 Things that influence ph (6) - Correct Ans-swimmer waste, disinfectants, water source, air borne debris, chemical balance, evaporation Low ph leads to (3) - Correct Ans-corrosive water, surface staining, surface etching If you have low ph, you must add - Correct Ans-soda ash (caustic soda - sodium carbonate) High ph leads to (5) - Correct Ans-scaling water, cloudy water, clogged filters, reduced circulation, eye/skin irritation If you have high ph, you must add ____ or _____ - Correct Ans-muriatic acid, sodium bisulfate Whole range of total alkalinity: ____ to _____ - Correct Ans-60, 180 Ideal range(s) of total alkalinity: ____ to _____ - Correct Ans-80, 120 The measure of the ability of the water to resist change in ph - Correct Ans-total alkalinity Acts as a ph buffer - Correct Ans-total alkalinity _____ will affect total alkalinity - Correct Ans-cyanuric acid If your ph is high, you will require a ______ total alkalinity - Correct Ans-lower If your ph is low, it is acceptable to have a ______ total alkalinity - Correct Ans-higher Low total alkalinity leads to (4) - Correct Ans-ph bounce, heater failure, surface etching, green water If you have low total alkalinity, add ______ - Correct Ans-sodium bicarbonate How much sodium bicarbonate should be added to increase total alkalinity? - Correct Ans-1.4 pounds per 10000 gal of water Pool Pool High total alkalinity leads to (4) - Correct Ans-ph lock, cloudy waters, clogged filters, reduced circulation If you have high total alkalinity, add _____ or ______ - Correct Ans-muriatic acid, sodium bisulfate Whole range for calcium hardness in a pool: ____ to ____ - Correct Ans-150, 1000 Ideal range of calcium hardness in a pool: ____ to ____ - Correct Ans-200, 400 Whole range of calcium hardness in a spa: ____ to ____ - Correct Ans-100, 800 Ideal range of calcium hardness in a spa: ____ to ____ - Correct Ans-150, 250 Amount of calcium content in the water - Correct Ans-calcium hardness Calcium hardness is measured as ______ - Correct Ans-calcium carbonate (caco3) Calcium not in solution (as a solid) is called _____ - Correct Ans-scale Calcium hardness is affected by _______ - Correct Ans-temperature When temp rises, calcium hardness becomes ______ - Correct Ans-less soluble Low calcium hardness leads to (3) - Correct Ans-corrosive water, wall stains, heater failure If you have low calcium hardness, add - Correct Ans-calcium chloride High calcium hardness leads to (3) - Correct Ans-scale, cloudy water, clogged filters The only way to lower calcium hardness is to _____ - Correct Ans-partially drain the water and replace it Max temperature of a pool or spa - Correct Ans-104 degrees At higher temps, there is an increased tendency for _____ - Correct Ans-scaling At lower temperatures, there is an increased tendency for ______ - Correct Ans corrosion Maximum total disolved solids - Correct Ans-1500 Saturation index equation: SI= - Correct Ans-ph + TF + CF + AF + TDSF Pool Green water - Correct Ans-presence of copper Red-brown water - Correct Ans-presence of iron Number one reason for cloudy water - Correct Ans-improper filtration Too much calcium in the water leads to - Correct Ans-scale Cause of foaming - Correct Ans-organic waste Three types of algae - Correct Ans-green, black, yellow Most common and most easily controlled algae - Correct Ans-green Algae resulting from poor pool circulation - Correct Ans-black Algae that is difficult to control and often requires_____ - Correct Ans-yellow, algaecide Pool capacity (in gallons) is equal to the pool _______ times _______ - Correct Ans volume, 7.5 gallons Minerals that cause stains (3) - Correct Ans-iron, copper, manganese Chemicals used to neutralize chlorine (2) - Correct A