Pool Ops Test with Verified Answers
Balanced water - Answer-- water that has all the correct levels of pH, Alkalinity, and
Calcium Hardness.
- These levels are important because it keeps the pool a safer and cleaner environment
for patrons to use
/.pH - Answer-The measure of how acidic or basic a substance is
/.Acceptable pH range - Answer-7.2-7.8.
/.Ideal pH range - Answer-- 7.4-7.6 because it results in the least irritation of the human
skin and eye.
- pH of the human eye is 7.5.
/.Effects of Low pH - Answer-Dissolves metals, stain surfaces, and can irritates human
eyes & skin.
/.Effects of High pH - Answer-Makes free chlorine levels less effective (Chlorine is
ineffective over a pH of 8.0), it irritates human eyes & skin, reduces circulation, clouds
water, and creates white film/crusty deposits.
/.Chemical to reduce pH - Answer-i. Muriatic Acid (HCl) and Sodium Bisulfate ("Dry
Acid") (NaHSO4).
/.Chemical to increase pH - Answer-Soda Ash (Na2CO3)
/.Total Alkalinity - Answer-- sum of alkaline substances in pool water
- buffer or a chemical system that resists change when an acid or base is added (like
muriatic acid)
- Water has no buffering ability on its own and without a buffer the pH can wander wildly
(pH Bounce), a good total alkalinity level will result in a stabilized pH.
/.Acceptable Total Alkalinity level - Answer-80 ppm-120 ppm
/.Effects of Low Alkalinity - Answer-Dissolves metals, stains surfaces, pH bounce
/.Effects of High Alkalinity - Answer-pH drifts upwards, clouds water, reduces circulation,
and creates crusty/filmy deposits
/.Chemical to increase alkalinity - Answer-Sodium Bicarbonate
/.Chemical to decrease alkalinity - Answer-Muriatic Acid (HCl)
, /.Calcium Hardness - Answer-Water without the correct level of calcium or magnesium
in it is soft, it allows soap suds to form easily at the waters surface. Calcium or
Magnesium is added to make pool water harder or to prevent that
- average of regular water is 80 ppm
- If pool water does not contain the correct concentration of calcium or magnesium, the
water will leach minerals from the whitecoat causing it to become weak and crack.
/.Acceptable Calcium Hardness levels - Answer-200 ppm-400 ppm
/.Effects of Low Calcium Hardness - Answer-Etches plaster, dissolves grout, and pits
pool decks
/.High Calcium Hardness - Answer-Causes heaters to work ineffectively, clouds water,
reduces circulation, forms white filmy, and crusty deposits
/.Chemical to increase Calcium Hardness - Answer-Calcium Chloride (CaCl2)
/.How to decrease calcium hardness - Answer-There is no chemical to decrease
calcium hardness levels, in order to decrease calcium hardness levels one must drain a
large volume of pool water out and add fresh water (Dilution).
/.Sanitation - Answer-the reduction of the level of micro-organisms by significant
numbers (usually 99.9% or more) to levels established by federal and state authorities.
/.Sanitizer - Answer-- A chemical or device that kills or inactivates the micro-organisms
present in a pool or spa
- Water without a sanitizer present can harbor algae, viruses, bacteria, fungi, and
protozoa
- Chlorine sanitizers and Bromine sanitizers oxidize or burn up organic containments
(Body oils, Hair gels, Sweat, Suntan lotion, and deodorant). As well as, pollen and dirt
/.Types of Sanitizers - Answer-Sodium Hypochlorite (NaClO) ("Chlorine"), Calcium
Hypochlorite (HTH, CaClO2), Chlorine gas (Dangerous, should not be used), Bromine,
Tri-chlor, and Di-chlor
/.The most commonly used sanitizer - Answer-- Sodium Hypochlorite breaks down
when it is added to water through a hypo-chlorinator
- breaks down when exposed to air, high temperatures, and direct sunlight
/.What happens when it is added to water - Answer-- water a reaction occurs that
results in hypochlorous acid, which is what disinfects the pool water
- The level of hypochlorous acid in the water is referred to as Free Chlorine (FC).
- After killing micro-organisms Hypochlorous acid breaks down into hydrogen ions (H2)
and Chlorite ions (OCl) and is no longer considered "Free Chlorine". This break down
can cause the pH to rise
Balanced water - Answer-- water that has all the correct levels of pH, Alkalinity, and
Calcium Hardness.
- These levels are important because it keeps the pool a safer and cleaner environment
for patrons to use
/.pH - Answer-The measure of how acidic or basic a substance is
/.Acceptable pH range - Answer-7.2-7.8.
/.Ideal pH range - Answer-- 7.4-7.6 because it results in the least irritation of the human
skin and eye.
- pH of the human eye is 7.5.
/.Effects of Low pH - Answer-Dissolves metals, stain surfaces, and can irritates human
eyes & skin.
/.Effects of High pH - Answer-Makes free chlorine levels less effective (Chlorine is
ineffective over a pH of 8.0), it irritates human eyes & skin, reduces circulation, clouds
water, and creates white film/crusty deposits.
/.Chemical to reduce pH - Answer-i. Muriatic Acid (HCl) and Sodium Bisulfate ("Dry
Acid") (NaHSO4).
/.Chemical to increase pH - Answer-Soda Ash (Na2CO3)
/.Total Alkalinity - Answer-- sum of alkaline substances in pool water
- buffer or a chemical system that resists change when an acid or base is added (like
muriatic acid)
- Water has no buffering ability on its own and without a buffer the pH can wander wildly
(pH Bounce), a good total alkalinity level will result in a stabilized pH.
/.Acceptable Total Alkalinity level - Answer-80 ppm-120 ppm
/.Effects of Low Alkalinity - Answer-Dissolves metals, stains surfaces, pH bounce
/.Effects of High Alkalinity - Answer-pH drifts upwards, clouds water, reduces circulation,
and creates crusty/filmy deposits
/.Chemical to increase alkalinity - Answer-Sodium Bicarbonate
/.Chemical to decrease alkalinity - Answer-Muriatic Acid (HCl)
, /.Calcium Hardness - Answer-Water without the correct level of calcium or magnesium
in it is soft, it allows soap suds to form easily at the waters surface. Calcium or
Magnesium is added to make pool water harder or to prevent that
- average of regular water is 80 ppm
- If pool water does not contain the correct concentration of calcium or magnesium, the
water will leach minerals from the whitecoat causing it to become weak and crack.
/.Acceptable Calcium Hardness levels - Answer-200 ppm-400 ppm
/.Effects of Low Calcium Hardness - Answer-Etches plaster, dissolves grout, and pits
pool decks
/.High Calcium Hardness - Answer-Causes heaters to work ineffectively, clouds water,
reduces circulation, forms white filmy, and crusty deposits
/.Chemical to increase Calcium Hardness - Answer-Calcium Chloride (CaCl2)
/.How to decrease calcium hardness - Answer-There is no chemical to decrease
calcium hardness levels, in order to decrease calcium hardness levels one must drain a
large volume of pool water out and add fresh water (Dilution).
/.Sanitation - Answer-the reduction of the level of micro-organisms by significant
numbers (usually 99.9% or more) to levels established by federal and state authorities.
/.Sanitizer - Answer-- A chemical or device that kills or inactivates the micro-organisms
present in a pool or spa
- Water without a sanitizer present can harbor algae, viruses, bacteria, fungi, and
protozoa
- Chlorine sanitizers and Bromine sanitizers oxidize or burn up organic containments
(Body oils, Hair gels, Sweat, Suntan lotion, and deodorant). As well as, pollen and dirt
/.Types of Sanitizers - Answer-Sodium Hypochlorite (NaClO) ("Chlorine"), Calcium
Hypochlorite (HTH, CaClO2), Chlorine gas (Dangerous, should not be used), Bromine,
Tri-chlor, and Di-chlor
/.The most commonly used sanitizer - Answer-- Sodium Hypochlorite breaks down
when it is added to water through a hypo-chlorinator
- breaks down when exposed to air, high temperatures, and direct sunlight
/.What happens when it is added to water - Answer-- water a reaction occurs that
results in hypochlorous acid, which is what disinfects the pool water
- The level of hypochlorous acid in the water is referred to as Free Chlorine (FC).
- After killing micro-organisms Hypochlorous acid breaks down into hydrogen ions (H2)
and Chlorite ions (OCl) and is no longer considered "Free Chlorine". This break down
can cause the pH to rise
