Recreational Water - Saraniecki Flashcards
What are the pool design basics?
(5 qualities)
Water recirc?
Capacity requirements?
Water connections?
Drainage?
Chemical requirements?
minimum 60% of water recirculation from gutters and skimmers
capacity of skimmers and gutters between 100-125% of pump recirculation capacity
indirect water connection to pool water supply lines
deck drains and pool water drained via air gap to the sewer system
automatic chlorinator and pH adjustments
What are swimming pool water standards chemically?
pH
Free Cl
Alkalinity
pH 7.2 - 7.8
spas 7.5-7.6
Free Cl 1.0 - 4.0 ppm
spas - 3.0-5.0 mg/l
Alkalinity 80 - 120 mg/l
data logs must be kept for two years
What are the pool temperature standards?
air temp 5F warmer than pool
suggested temp 80F
Temp should never exceed 85F
How do you calculate pool volume or a rectangular pool?
Round?
rectangular/squar - LxWxAvg depthx7.5 = gallons
round - diameter^2 x 5.9 OR pi r^2 x avg depth x 7.5
What are the turnover rates for pools?
public - 6-8 hrs
private - 12 hrs
wading - 1 - 2 hrs
spa - 30 mins
How do you calculate turnover?
(pool capacity)/[flow meter reading gpmx60]
Describe sand filters (2)
rapid sand pressure filter - 3 gpm/sqft, least effective filtration, old large pools
high rate sand filter - 5-20 gpm/sqft, uses finer grades of sand than rapid
Describe diatomaceous earth filters
fossilized diatoms - single celled plants
light, porous honeycomb structure of sharp edges
enormous surface area
chap, natural, stable
more surface area than sand with slower filtration 1-2gpm/sqft
How does chlorine kill microorganisms?
by attacking the lipids in the cell walls and destroying the enzymes and structures within the cell
What is a very poor choice of pool sanitizer?
chloramine
Describe hypochlorous acid
acts within several seconds
80 to 150x more effective than OCl, monochloramine, dichloramine
concentration is pH dependent, acidic conditions favor hypochlorous acid
Describe hypochlorite ion
can take up to 30 mins
What could cause sudden jumps in pool pH?
algae growth, precipitation, alkalinity
What is the definition of pH?
measure of the activity of dissolved hydrogen ions
low - high H+ conc
high - low H+ conc
Salvato - the logarithm of the reciprocal of hydrogen ion concentration
How would you read results of a phenol-red test of a pool?
pH ok pink to orange
yellow - low pH
purple - too high pH
Why should you always add acid to water first?
when added to water, two acids are formed - hypochlorous acid (HOCl) and hydrochloric acid (HCl)
Hypochlorous acid can then form an acid and an ion - hypochlorous acid and hypochlorite ion OCl-
Compare Bromine sanitation to Chlorine
more expensive
better residual - decent sanitizer
same dpd kit but x2.25
residual 3-5 mg/l, spas 4-6 mg/l
lowers pH of water
easily destroyed by UV, cyanuric acid does not help
Compare saltwater pools
basically a chlorine pool as it is a byproduct
easiest to maintain
expensive upfront but lower cost overall
pH keeps rising
salt 3100-3400 ppm
Why superchlorinate?
even with free chlorine at 1-4 ppm, there will still be:
algae
pseudomonas aeruginosa
entamoeba histolytica
schistoma ssp
giardia lamblia
syrptosporidium spp
How do pools control algae?
continuous circulation and chlorination
eliminate with superchlorination or copper sulfate as second
algaecides
When does a public pool need to be shocked?
total chlorine - free chlorine = combined chlorine
when CC values are freater than 0.2mg/l
How much chlorine to superchlorinate?
To bring it to Breakpoint - where the amines are cleaved off the chloramines
10x the value for CC
Describe ozone as a pool decontaminant
3000 times faster than chlorine
very volatile, short life, no residual
needs to be constantly produced on site
Describe ultraviolet as a pool decontaminant
effective
short life with no residual
needs to be constantly produced on site
usually used in conjunction with chlorine or bromine
What is TDS? Limit? Solution?
Total dissolved solids
TDS about 1500 ppm yields reduced Cl efficiency and cloudy water
only solution is dilution
What is the Langelier Index?
saturation index
simple calculation that considers pH, temperature, calcium hardness, alkalinity
ideal is near 0
+ results in scaling
- results in corrosion
How are public beaches regulated?
any changes requires sanitary survey
EPA recommended standards -
fecal coliform no less than 5 samples over 30 days, no more than 200 colonies/100 mL, no more than 10% of samples in 30 days to exceed 400 colonies/ 100 mL
pH 6.5 - 8.3
samples collected every 300ft in 2 ft of water
density 50sqft to 200 sqft/person
8 in secchi disk in 4 ft water for clarity
Where should chemicals be stored?
secure and dry
separate from test equipment
out of sun light
55-70F, 60F is the best
max storage temp 95F
VOCs should not be allowed to off gas in closed environment
What should happen during a formed stool incident?
evacuate bathers
remove fecal material with net or scoop
raise Cl to 2ppm, pH 7.2-7.5 temp 77F
30 mins CT
establish fecal accident log
What is formed stool protocol based on ?
Giardia lamblia inactivation
What should happen during a diarrheal fecal incident?
evacuate bathers, remove what you can
raise free Cl to 20 ppm
12.75 hours CT
cyanuric acid must be under 50 ppm
What should happen during vomit and blood contamination in a public pool?
vomiting is usually the result of swallowing too much water and is probably not infectious
if full contents vomited, follow formed stool fecal protocol
for blood, if free cl was 1.0 ppm, no reason to close pool or further sanitize pool water
What life saving equipment is required?
12-15 ft shepherd’s hook
Coast Guard approved 18” float ring, 50ft 1/4” line
back or spine board
first aid kit
appropriate signage - no diving, depth
all metal electrically bonded together within 5’ water’s edge
What is required at pools thanks to the consumer product safety act?
anti-entrapment drain cover
vacuum release system
auto-pump shut off
enclosure barriers and automatic gates
no main drain
pool alarm
pool safety cover
gravity drainage
What are the specs on pool fencing requirements?
min 4’ high
self closing out swinging door
door latch must be more than 40” off the ground
