Pools 2017 Flashcards
How should samples be taken from a swimming pool?
samples should be taken at 12-18” depth with forward sweeping motion
What does Orthotoluene do?
measures total residual chlorine
this test is heat sensitive
What is DPD and what does it do?
diethyl-phenylene-diamine
measures free and combined levels of chlorine
not heat sensitive
more accurate than Ortho tests
What are recirculating swimming pools and the minimum turnover?
traditional pools
pools - 6 hours
spas - 0.5 hrs
wading pools - 1 hr
What is the ideal pH of a pool?
7.2-7.8
What happens when a pool pH is too low? Too high?
pH<7 - corrosion
pH>7 - scale deposits
What is sodium thiosulfate and when is it used in pools?
chemical that neutralizes chlorine
used when free Cl may affect test results
What are soda ash and caustic soda alternatively know as and what are their purposes?
soda ash - sodium carbonate
caustic soda - sodium hydroxide
bases used to raise pool pH
What is muriatic acid alternatively known as and what is it used for?
hydrochloric acid
used to lower pH
What is Cyanuric acid and when should it be used?
chlorine stabilizer which prevents excessive dissipation of Cl from sun light exposure
should be used when levels between 40-60ppm (Cl maintained at 1.5 ppm min)
Ineffective if >100 ppm
What is significant about copper in pools?
if Cu test performed and resulting concentrations of >0.2 ppm, pool water needs to be changed
When should clarity be an important consideration in pool inspections?
pool to be closed if bottom pool main drain is not visible due to cloudiness
What is copper sulfate used for in pools?
to control algae growth problems
How do you calculate the occupancy load of a pool?
surface area of pool/20
How do you calculate the occupancy load of a spa?
surface area of spa/10
What are the rules regarding public pools and diving?
No diving for pools that are six feet or less deep
Must have appropriate NO DIVING signage
letters must be at least 4” high
What are the life ring requirements for a public pool?
must have attached rope long enough to span the maximum width of the pool
must be at least 17” in diameter
must be in easily accessible area
rope must be 3/16”
What are requirements of body hooks at public pools?
must be permanently attaches to a rescue pole that is at least 12 ft in length
What is required of pools built after 1994?
a self-closing, self-latching gate with latch at least 3.5 fit above deck and fence at least 5 ft high
openings/holes/gaps in fence must be no larger than 4”
bottom of fence hall be no higher than 2” off dirt or 4” off cement
What is GFCI and what are the requirements around it?
Ground-fault circuit interrupters
all pool light fixtures muse have been fitted with one by May 1, 199 and it must have been inspected by a qualified inspector by that date
What is the Ryznar index?
point of calcium carbonate stability
What is the Caldwell-Lawrence Index?
solves water conditioning problems
What is the Langelier index?
determine calcium carbonate stability for corrosion control
25-50 ppm
What is the equation to determine the volume of a rectangular pool?
LxWxAvg Depthx7.5
What is the equation for required flow rate of a pool?
Pool Volume/Turnover rate x 60
What is the equation for required filter area?
Flow rate /(GPM/sqft)
What is the equation to determine water loss
LxWx(loss in inches/12)x#ofDays
What is the equation for total chlorine?
combined chlorine + free cholrine
How do you calculate chlorine residual in ppm?
(lbs of product x % str x 1000000)/(vol x 8.3)
1 gallon of water is how many lbs?
8.34
