POOL OPERATOR PRACTICE EXAMS ANSWERS AND
QUESTIONS SET A+
✔✔dichlor - ✔✔-anhydrous
-dichlor dihydrate
-a salt, very soluble
-used to superchlorinate pool and raise stabilizer level
✔✔anhydrous dichlor - ✔✔-no water is bound to molecule
-class 3 oxidizer
✔✔dichlor dihydrate - ✔✔class 1 oxidizer
✔✔bromine - ✔✔-disinfectant
-oxidizer
-reddish brown liquid
✔✔hypobromous acid (HOBr) - ✔✔-weak acid
-destroyed by sunlight
✔✔bromine tablets (BCDMH) - ✔✔-when dissolved in water, HOBr acid and HOCl acid
are released
✔✔ozone (O3) - ✔✔-supplemental oxidizer and disinfectant
-cannot be transported and must be generated on site
-venturi injection is the most common way to dissolve ozone into water
✔✔ultraviolet light - ✔✔-supplemental oxidizer and disinfectant
-does not create a disinfectant residual in water
-must be used in conjunction with a disinfectant that provides a residual
-kills/inactivates bacteria, viruses and parasites like crypto and giardia
-inactivates pathogens with high energy
, ✔✔the effectiveness of UV as a disinfectant is based on - ✔✔the applied energy within
the given area of the treatment chamber where the UV bulb is located
✔✔chlorine dioxide - ✔✔-selective oxidizing agent and disinfectant
-used to kill bacteria, algae, viruses and microscopic cysts like crypto and giardia
-does not react with ammonia
✔✔PHMB - ✔✔-organic polymeric disinfectant
-used in conjunction with hydrogen peroxide
-not compatible with common products like chlorine-releasing chemicals, copper
algicides and potassium monopersulfate
-kills mildew and slime
✔✔pH stands for - ✔✔potens hydrogen = power of hydrogen
✔✔pH - ✔✔a measurement of the hydrogen ion concentration in water
✔✔the smaller the pH the more ____ the solution - ✔✔acidic
✔✔water that has a pH of 6 is ___ times more acidic than water that has a pH of 7 -
✔✔10
✔✔what is the acceptable pH of pool/spa water that is slightly alkaline? - ✔✔7.2-7.8
✔✔ideal range for pH is - ✔✔7.4-7.6
✔✔to lower the pH add - ✔✔acids or acid salts such as bisulfate
✔✔to increase pH add - ✔✔a basic material
most common, sodium carbonate
other bases: sodium hydroxide, sodium sesquicarbonate
✔✔total alkalinity - ✔✔-a measure of the ability of water to resist changes in pH
-is a buffer
-like an anchor for keeping pH where it should be
✔✔the ideal total alkalinity for high pH disinfectants is - ✔✔80-100 ppm
✔✔the ideal total alkalinity for low pH disinfectants is - ✔✔100-120 ppm
✔✔water will exhibit pH bounce when the total alkalinity is ___ - ✔✔low
✔✔low total alkalinity may result in - ✔✔pH bounce
etching of pool/spa surface
QUESTIONS SET A+
✔✔dichlor - ✔✔-anhydrous
-dichlor dihydrate
-a salt, very soluble
-used to superchlorinate pool and raise stabilizer level
✔✔anhydrous dichlor - ✔✔-no water is bound to molecule
-class 3 oxidizer
✔✔dichlor dihydrate - ✔✔class 1 oxidizer
✔✔bromine - ✔✔-disinfectant
-oxidizer
-reddish brown liquid
✔✔hypobromous acid (HOBr) - ✔✔-weak acid
-destroyed by sunlight
✔✔bromine tablets (BCDMH) - ✔✔-when dissolved in water, HOBr acid and HOCl acid
are released
✔✔ozone (O3) - ✔✔-supplemental oxidizer and disinfectant
-cannot be transported and must be generated on site
-venturi injection is the most common way to dissolve ozone into water
✔✔ultraviolet light - ✔✔-supplemental oxidizer and disinfectant
-does not create a disinfectant residual in water
-must be used in conjunction with a disinfectant that provides a residual
-kills/inactivates bacteria, viruses and parasites like crypto and giardia
-inactivates pathogens with high energy
, ✔✔the effectiveness of UV as a disinfectant is based on - ✔✔the applied energy within
the given area of the treatment chamber where the UV bulb is located
✔✔chlorine dioxide - ✔✔-selective oxidizing agent and disinfectant
-used to kill bacteria, algae, viruses and microscopic cysts like crypto and giardia
-does not react with ammonia
✔✔PHMB - ✔✔-organic polymeric disinfectant
-used in conjunction with hydrogen peroxide
-not compatible with common products like chlorine-releasing chemicals, copper
algicides and potassium monopersulfate
-kills mildew and slime
✔✔pH stands for - ✔✔potens hydrogen = power of hydrogen
✔✔pH - ✔✔a measurement of the hydrogen ion concentration in water
✔✔the smaller the pH the more ____ the solution - ✔✔acidic
✔✔water that has a pH of 6 is ___ times more acidic than water that has a pH of 7 -
✔✔10
✔✔what is the acceptable pH of pool/spa water that is slightly alkaline? - ✔✔7.2-7.8
✔✔ideal range for pH is - ✔✔7.4-7.6
✔✔to lower the pH add - ✔✔acids or acid salts such as bisulfate
✔✔to increase pH add - ✔✔a basic material
most common, sodium carbonate
other bases: sodium hydroxide, sodium sesquicarbonate
✔✔total alkalinity - ✔✔-a measure of the ability of water to resist changes in pH
-is a buffer
-like an anchor for keeping pH where it should be
✔✔the ideal total alkalinity for high pH disinfectants is - ✔✔80-100 ppm
✔✔the ideal total alkalinity for low pH disinfectants is - ✔✔100-120 ppm
✔✔water will exhibit pH bounce when the total alkalinity is ___ - ✔✔low
✔✔low total alkalinity may result in - ✔✔pH bounce
etching of pool/spa surface
