and CORRECT Answers
To prevent a bather from diving into too shallow of water, depth markers should be - CORRECT
ANSWER - On horizontal surfaces around the pool, on vertical surfaces within the pool, a
minimum of every 20 feet.
Why is high pH a problem in a swimming pool? - CORRECT ANSWER - Irritate eyes of
patrons, reduces effectiveness of chlorine, results in cloudy water
Cyanuric acid is sometimes used as a stabilizer and must never exceed - CORRECT
ANSWER - 50 ppm
Which filter type removes the smallest particle size? - CORRECT ANSWER - Diatomaceous
Earth
Algae primarily forms in a pool because of - CORRECT ANSWER - poor water circulation
A skimmer weird - CORRECT ANSWER - prevents floating debris from re-entering the pool
If you need to raise free chlorine quickly, how long should patrons wait after manually adding
chlorine to the pool? - CORRECT ANSWER - 30 minutes
If swimmers complain of a chlorine odor (from chloramines), it can best be removed by
a. breakpoint chlorination
b. doing nothing, odor will gradually disappear
c. adding soda ash
d. Backwashing - CORRECT ANSWER - A. Breakpoint chlorination
, acceptable level of free chlorine in swimming pool is - CORRECT ANSWER - 1-3 ppm
acceptable level of free bromine in swimming pool is (1,3,5, or 8) - CORRECT ANSWER -3
ppm
To lower the pH, what may be added to the water - CORRECT ANSWER - Muriatic Acid
What chemical should you use to raise the calcium hardness? - CORRECT ANSWER -
Calcium Chloride
The hypochlorinator appears to be working, but no chlorine is in the pool. What could be the
problem? (3) - CORRECT ANSWER - 1. Hypochlorinator tubing may be damaged
2. Liquid chlorine vat may be empty
3. Injection fitting might be clogged
Recommended range for pH - CORRECT ANSWER - 7.2-7.8
Stains on the interior pool surfaces are usually caused by - CORRECT ANSWER - Iron
Backwashing is complete when - CORRECT ANSWER - the water in the sight glass is cear
Process of reversing water flow to remove particles from a sand filter - CORRECT
ANSWER - Backwashing
What is used to raise pH - CORRECT ANSWER - soda ash
What type of algae can penetrate into the plaster of pool surface and cause damage to the pool -
CORRECT ANSWER - black algae