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Flashcards in Pools Deck (73):
1

what are the 4 leading causes of accidental deaths

1. car accident
2. falls (number one injury at home)
3. fires
4. drowning

2

what is the leading cause of work related accidental death

fires and explosions

3

what is the ideal human body temperature

98.6 F

4

about ____ quarts of water can be expelled from the human body a day

6 quarts

5

how do you convert fahrenheit to celsius

F -32
/9
x 5

6

convert 95F to celsius

35

7

how do you convert Celsius to fahrenheit

C x 9
/5
+ 32

8

kelvin = celsius + _____

273

9

a 32F day with a 20 mph wind could cause windchill temperatures down to ____

0F

10

high altitude is any elevation above ____ft (__ miles)

5280 feet or one mile above sea level

11

at one mile above seal level there is ____ % less oxygen and also less _____

40-45% less oxygen

also less humidity

12

It takes the average human body ________ days to acclimate to extreme conditions

10-14 days

13

What are the minimum turnover rates for

pool
spa
spray ground
wading pool
medical pool

pool 6 hours
spa 30 minutes
spray ground 30 minutes
wading pool 1 hour
medical pool 2 hours

14

What is the minimum flow (gpm) for a 50,000 gallon pool

139 (50k/360 mins)

15

DE filters
composition
maximum gpm/ft2

composition - microscopic diatoms (aquatic marine life), calcified, appears like coffee grounds

maximum filtration of 2 gpm/sq foot of filter area

16

The in and out pressure of a filter should never differ by more than ________ psi

if so the filter needs to be ________

10

backwashed/cleaned/replaced

17

Cartridge filter max gpm/sq ft

.375 gpm/sq ft

18

the best type of filter for a pool with more than 30,000 gallons is ____________

sand filter

19

the most popular type of filter for a spa is __________

cartridge

20

the best type of filter for a pool with less than 30,000 gallons is _____________

DE filter

21

sand filters are (more/less) efficient than DE filters

less efficient, but offer faster filtration

22

Rapid Sand Filter
max filtration rate
minimum depth of media ______
minimum depth of filter gravel___________
effective particle size between ___ and ___ mm
uniformity coefficient not exceeding _____

3 gpm/sq ft

min media depth - 20 inches
min filter gravel depth - 10 inches

particle size - .40 - .55 mm

max coefficient 1.75

23

High Rate Sand Filters
max filtration rate
effective particle size between ___ and ___ mm
uniformity coefficient not exceeding _____

15 gpm/sq ft
.40 - .55 mm
max coefficient 1.75

24

Public pool water quality
standard plate count (heterotrophic plate ocunt) shall not exceed _____ CFU per ml

total coliform
membrane filtration method - must be less than ___ CFU per 100 ml
multiple tube fermentation method - must be less than _____ CFU per 100 ml

standard 200 CFU per ml

total coliform
membrane filtration - 1 CFU per 100 ml
fermentation - 2.2 CFU per 100 ml

25

All pool equipment must be certified by what standard?

NSF/ANSI 50-2012

26

Chlorine in water breaks into _____ and _____ which together are called _______________

XCl + H20 ---> HOCL (Hypochlorous Acid) and OCL- (Hypochlorite ion) + H+ (Hydrogen ion)

together they are Free Chlorine

27

_____________ is the active killing form of chlorine in water

HOCL, Hypochlorous Acid

28

Chloramines form when Free chlorine binds with ___________.

Chloramines are not an effective __________

contaminants in the water, usually ammonia compounds.

not an effective disinfectant

29

unstabilized vs stabilized chlorine disinfectants

unstable - no Carbon atom - sensitive to UV light
stable - contain carbon atom - not sensitive to UV light

30

Name 6 types of chlorine disinfectants, their physical appearance, stable/unstable, and available chlorine content

unstable
sodium hypochlorite - NaOCl - liquid - 11%
calcium hypochlorite - Ca[OCl]2 - granular, tabs - 70%
lithium hypochlorite - LiOCl - granular - 35% (not used often)
chlorine gas - CL2 - gas - 100%

stable
trichlor - C3N3O3CL3 - tablets mostly, granular - 90%
dichlor - NaCL2C3N3O3 - granular - 60%

31

the most pH neurtral chlorine type is _____

dichlor

32

What is cyanuric acid

added to protect unstabilized chlorine form the effects of sunlight.

33

Bromine disinfectant

tablets usually, 27% available bromine content

used more in spas because it naturally lowers the pH

can be destroyed by sunlight but cyanuric acid does not work for bromine

34

Name some other methods that can be used to disinfect public pools

ozone (gas)
chlorine generation (salt)
UV light

35

free chlorine requirements for pools and spa/wading/sprayground

with and without CYA

w/o cya
pools min 1, max 10
spas min 3 max 10

w/ cya
pools min 2 max 10
spas min 3 max 10

36

bromine residual minimum in pools vs spas

pools min 2ppm, spas/wading/spray min 4ppm

37

minimum and maximum pH
maximum CYA concentration
max combined chlorine concentration
max spa temp

7.2-7.8
100 ppm CYA max
max .4 ppm combined chlorine
max spa temp 104F

38

a wading pool has a max depth of ___

18 '' at the deepest point

39

What are the two types of tests for pool/spa water

Orthotoludene (ortho test) - measure total chlorine, heat sensitive
DPD - Diethyl-Phenylene-Diamine - measures free chlorine, combined chlorine, not heat sensitive

40

sample water should be taken at a depth of ______

12-18 inches

41

What are two common chemicals used to raise the pH and one common chemical to lower the pH

raise pH
Sodium carbonate "soda ash" NaCO3
Sodium hydroxide "caustic soda" NaOH

lower pH
Hydrochloric acid "muriatic acid" HCL

42

copper in pool water can not be above _____ ppm

.2 ppm

43

TDS (water hardness) should be between ___ and ___ ppm

175-300 ppm

TDS = total dissolved solids

44

Which chemical is commonly used to neutralize chlorine

Sodium thiosulfate

45

algae growth can be controlled by used what chemical

Copper sulfate (CuSO4)

46

in swimming pools ___% of water going through the skimmer and ___% goes through the main drain

75% skimmer
25% main drain

47

What does "feet of head/head pressure" mean in regards to the pump

the flow pressure of resistance caused by the pipes and equipment

48

an increase in the head pressure results in ______

a reduction of flow

49

What is cavitation

bubbling in the circulation system which can damage the pump

50

What is the required dynamic head capacity for a pump paired with the follow type of filters

pressure DE
vacuum DE
rapid sand
high rate sand
cartridge

pressure DE 60ft
vacuum DE 20'' vacuum, 40 ft head
rapid sand 45 ft
high rate sand 60 ft
cartridge 60 ft

51

a lifeguard must have what type of training?

American Red Cross or YMCA

CPR certification

52

pool records must be kept for ___ years

2 years

53

which safety devices must be at a public pool

17 '' maximum life ring
12 foot minimum body hook

54

what to do for pool fecal/vomit/blood contamination events

formed fecal/vomit:
diarrhea:
blood:

close the pool, ensure pH is 7.5 or lower and water temperature is 77F or higher

formed fecal/vomit - maintain FC 2ppm for at least 25 minutes

diarrheal stool 20 ppm chlorine for at least 12.75 hours

if CYA present: lower pH to 6.5 40 ppm FC for at least 30 hours

blood - check if FC is within range, if in range pool stays open

backwash filters, replace cartridge filters

document incident

55

what is an ancillary facility

areas used in conjunction with pool - locker rooms, pool deck, showers etc.

56

a depth line is required at ____ feet for pools that are deeper than ___ ft

4.5 feet if deeper than 5 feet

57

pools deeper than ___ feet require a no diving marker

6 feet

58

pool/spa decks must be a minimum of ___ feet

4 feet

59

pool enclosure must be ___ feet high with gaps not to exceed ____ inches

horizontal bars must be a minimum of ___ feet apart

5 feet high

no more than 4'' spacing

horizontal bars 4 feet apart

60

chain link fencing can be used if not greater than ___ inches horizontally

1.75 ''

61

what are the pool and spa capacity

spa 1 user per 10 sq ft (surface area/10)

pools 1 user per 20 sq ft (surface area /20)

62

studies indicate that swimmers have a higher overall illness rate of non swimmers:

regardless of bathing water quality
due to poor regulatory practice3
if they are over 50 years old
if they swim in pools

regardless of bathing water quality

63

the treatment system of a pool is typically recommended to be installed in which of the following flow arrangements?

skimmer/gutter line
adjustment valves
main drain line
hair strainer
pump
pH feeder
filter
filter aid pumps
adjustable inlets
disinfectant feeder

skimmer/gutter line
main drain line
adjustment valves
hair strainer
filter aid pump
filters
disinfectant feeder
pH feeder
adjustable inlets

64

swimming pool water clarity is measured in NTU or nephelometer turbidity units. It is recommended that a level of 0.5 NTU

shall be maintained
shall no be exceeded
is the minimum
is the maximum

shall not be exceeded

65

when mixing acid and water always...

add water to acid
add acid to water
add soda ash to acid
stir while pouring water into the acid

add acid to water

66

when chlorine is added to water...

one acid is formed
two primary acids are formed
HCl is considered the primary product
ozone is produced in large quantities

two primary acids are formed

67

the best control of swimmers itch at a bathing beach is to

add copper sulfate
increase the chlorine residual
lower the chlorine residual
lower the water level and allow plants to dry out

add copper sulfate

68

swimmers itch is caused by

algae growth

69

the preferred method for controlling sewage from watercraft is the use of...

onboard holding tanks
shipboard discharge
incinerator toilet
compost toilet

onboard holding tanks

70

the microbe primarily responsible for skin infecitons in whirlpools is

e coli
pseudomonas aeruginosa
shigella sonnet
salmonella typhi

pseudomonas aeruginosa

71

water in wading pools should be recirculated every

60 mins
90 mins
120 mins
180 mins

60 mins

72

the following type of swimming facility is generally prohibited

home outdoor pool
fill and draw pool
natural flow through pool
recirculating pool

fill and draw pool

73

the main drain should have a grate that is how much larger than the area of the discharge pipe to prevent dangerous suction effets

four times
five times
six times
seven times

four times larger