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PUBLIC POOLS

W A T E R Q U A L I T Y&

R E C O R D K E E P I N GS T A N D A R D S

For Public Pools Operating in

Newfoundland and Labrador

Department of Health and Community ServicesDisease Control and Epidemiology Division

RECREATIONAL2002-01March 2004

Table of ContentsPage Number

Section 1: Water Quality Parameters 1

A) Chemical Parameters 11) pH 12) Total Alkalinity 13) Hardness 24) Disinfectants 25) Stabilizer (Cyanuric Acid) 3

B) Physical Parameters 4

C) Bacteriological Standards 4

Section 2: Testing Methodology 5

A) Requirements for Pool Operators 5

B) Requirements for Environmental Health Officers III 6

Section 3: Equipment 6

Section 4: Record Keeping 7

Section 5: Trouble Shooting 7

Section 6: When to Close a Pool 13

Section 7: References 14

Section 8: Appendices 15

# 1 Table of Water Quality Requirements for Various Classesof Public Pools

# 2 Form A: Daily Record of Operation - for Use in all Public Pools Except Class B: Whirlpool, Spa Types of Pools

# 3 Form B: Daily Record of Operation - for Use in all Class B:Whirlpool, Spa Types of Pools

# 4 Cleaning and Disinfecting Pools Contaminated With FecalMaterial and/or Vomit

# 5 Glossary

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SECTION 1: WATER QUALITY PARAMETERS

A) CHEMICAL PARAMETERS

There are five main chemical parameters which are important in the operation of publicpools. They are:

1) pH

• pH is defined as a measure of the acidity and basicity of pool water.

• Recommended range in public pools: 7.2 - 7.8

• Pool Problems:

Low pH High pH

Problem

corrosion scaling

chlorine loss chlorine inefficiency

staining cloudy pool

eye & skin irritation eye & skin irritation

2) Total Alkalinity (TA)

• Total alkalinity (TA) is the measurement of the ability of pool water to resist changesin pH. Total alkalinity is the governor of pH.

• Recommended range in public pools: 80 - 120 ppm (ppm - parts per million)

• Pool Problems:

Low TA High TA

Problem

pH bounce pH drift to 8.4

corrosion scaling


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3) Hardness

• Hardness is the amount of calcium in solution in pool water.

• Recommended range in public pools: 200 - 300 ppm

• Pool Problems

Low Hardness High Hardness

Problem

water will etchplaster, pit metal orroughen poolsurfaces

scaling


4) Disinfectants

• A disinfectant is an agent which reduces the level of micro-organisms present insignificant numbers (usually 99.9% or more) to safe levels as established by Federalor Provincial Health Authorities.

• Chlorine and bromine compounds are the most common disinfectants used in publicpools.

• Chlorine is available in many forms such as chlorine gas, calcium hypochlorite,sodium hypochlorite, lithium hypochlorite, Trichloro-S-Triazinetrione and SodiumDichloro-S-Triazinetrione. Recommended residuals for free available chlorine (FAC)in public pools are as follows:

1. All Public Pools Classes Except Class B: Whirlpool, Spa Types of Pools:

• Indoor Pools: 1.5 ppm (minimum acceptable limit 0.5 ppm)

• Outdoor Pools: 3.0 ppm (minimum acceptable limit 1.0 ppm)

Note: The FAC residual should not be greater than 5 ppm when bathersare in the pool water.

2. Class B: Whirlpool, Spa Types of Pools

• Indoor and Outdoor Pools: 2 - 3 ppm

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• Bromine used in public pools is available in two forms. They are:- organic bromine and- sodium bromide and potassium monopersulfate

Recommended residuals for total bromine are:

1. All Public Pools Classes Except Class B: Whirlpool, Spa Types of Pools

• 2 - 3 ppm

2. Class B: Whirlpool, Spa Types of Pools

• 2 - 4 ppm

5) Stabilizer (Cyanuric Acid)

• Ultraviolet rays of sunlight dissipate free available chlorine in outdoor pools quickly. Thus, stabilizer is used in outdoor pools to prevent chlorine from evaporating ordissipating from the pool water. The stabilizer used in outdoor pools is cyanuric acid. Chlorine residuals (free available chlorine) stabilized with cyanuric acid usually laststhree to five times longer. Please note that a stabilizer is not recommended forindoor pools.

• There are two choices to ensure cyanuric acid is present in outdoor pools. They are:

- use of a stabilized chlorine- separate use of an unstabilized chlorine and a stabilizer

• Recommended range for cyanuric acid in outdoor pools: 25 - 50 ppm

• Cyanuric acid should not exceed 100 ppm. Levels above this limit reduce thedisinfecting power of chlorine.

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B) PHYSICAL PARAMETERS

1. Water Temperature

Recommended water temperature range:

1. All Public Pools Classes Except Class B: Spa/Whirlpool Types of Pools

• 21°C - 32°C

2. Class B: Spa/Whirlpool Types of Pools

• 36°C - 38°C

C) BACTERIOLOGICAL STANDARDS

There are five bacteriological standards that public pools must meet. They are as follows:

Test Standard Comment

E. coli 0

per 100 ml sample

Note: repeat sample must be taken to

confirm presence of E. coli

Indicator of the effectiveness of

disinfection and recent fecal

contamination

Staphylococcus aureus 50

or less

per 100 ml sample


confirm presence of Staphylococcus aureus

at levels above the standard

Indicator of water contamination

Pseudomonas

aeruginosa

10 or fewer

per 100 ml of sample


confirm Pseudomonas aeruginosa


This organism is a pathogen in pools,

spas and whirlpools.

Standard Plate Count 250 or fewer

per 1 ml of sample

Note: repeat sample to confirm SPC


Indicator of a deficiency in the

treatment process

Some of the above-noted tests can be performed through the Government ServiceCentre/Testing Site. Other tests can only be performed at the Newfoundland and LabradorPublic Health Laboratory in St. John’s.

The summary of the water quality requirements are outlined in Appendix 1.

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SECTION 2: TESTING METHODOLOGY

A) REQUIREMENTS FOR POOL OPERATORS

All pool operators are to perform and record the following tests at the indicated timeintervals:

Test Time Intervals(Frequency)

Comments

1) Free Available ChlorineResidual if used as adisinfectant for the pool

½ hour before opening andevery four hours when pool is inoperation

This is the level of theuncombined chlorine in the poolwater available to kill harmfulgerms

2) Total Chlorine Residual ifused as a disinfectant for thepool


Total chlorine residual isdefined as the sum of theuncombined chlorine (freeavailable chlorine) and thecombined chlorine. Combinedchlorine is the free availablechlorine which has combinedwith wastes to producechloramines. Combinedchlorine has very littledisinfecting power but causesthe chlorine odour in a pool. Itis also responsible for eyeirritation. The total chlorineresidual must not exceed thefree available chlorineresidual by more than 0.5 ppmin the pool. Example: If thefree available chlorine residualis 0.8 ppm then total chlorineresidual in the pool must not begreater than 1.3 ppm.

3) Total Bromine Residual ifused disinfectant in the pool


This is level of bromine in thepool water available to killharmful germs

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Test Testing Frequency Comments

4) pH ½ hour before opening andevery four hours when pool is inoperation

High or low pH can affect theefficiency of chlorine to killharmful germs

5) Water Temperature a) once a day for all public poolclasses except Class B:whirlpool, spa types of pools

b) every four hours for Class B:whirlpool, spa types of pools

This is important for the comfortof users of the pool.

6) Total Alkalinity a) once a week for all publicpool classes except Class B:whirlpool, spa types of pools

b) once a day for Class B:whirlpool, spa types of pools

This is important in maintainingthe recommended pH levels in apool.

7) Hardness once a week May cause staining orcloudiness if the proper levelsare not maintained.

8) Stabilizer (Cyanuric Acid) -Used in outdoor pools only

a) once a week for all publicpool classes except Class B:whirlpool, spa types of pools

b) once a day for Class B:whirlpool, spa types of pools

Use to prevent chlorine fromevaporating or dissipating fromthe pool water

B) REQUIREMENTS FOR ENVIRONMENTAL HEALTH OFFICERS

During each visit, EHOs should carry out the same tests as required by the pool operators[see section 2(A) above]. In addition, the EHO should routinely collect water samples forbacteriological testing [see section 1(C) - Bacteriological Standards for the various typesof tests].

SECTION 3: EQUIPMENT

Pool operators and EHOs should have equipment capable of testing the following pool waterparameters:

- Free Available Chlorine - Hardness - Cyanuric Acid (if stabilizer used)

Residual - pH- Total Chlorine Residual - Temperature - Total Bromine Residual - Total Alkalinity

(if bromine is used as a disinfectant)

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SECTION 4: RECORD KEEPING

Daily pool operational records must be maintained by the pool operator and be available forauditing by the EHO. An audit of the records should be performed during each scheduledinspection. Records audited by the EHOs should be initialed.

For all public pools except Class B: whirlpool, spa types of pools, operators must use Form A:Daily Record of Operation (see Appendix # 2). For Class B: whirlpool, spa types of pools (asdefined in Section 4(1) b(ii) of Public Pool Regulations, 1996), operators must use Form B: DailyRecord of Operation (see Appendix # 3).

Data must be retained for a period of one year from the date of making the record.

SECTION 5: TROUBLE SHOOTING

As listed below, this section identifies the most common water quality problems experienced inswimming pools, determines the possible causes and provides possible recommendations(remedies) to issue.

PROBLEM POSSIBLE CAUSE REMEDY

ALGAE GROWTH• green algae

• slippery walls

• algae stains

• black algae

� Hot sunny weather K Maintain high free availablechlorine (FAC).

� Pool temperature too high K Keep below 26.7°C (80°F).

� Poor circulation (dead spots inpool)

K Reposition directional outletsand check efficiency of pump. Hand dose corners. Checkflow rate.

� Low wet spots on deck K Eliminate, if possible. Handdose with dry chlorine.

� Low free available chlorine(FAC)

K Maintain a FAC greater than5.0 ppm overnight. Brushwalls vigorously, then vacuum. Add algicide and adjust PH.

� Total available chlorine (TAC)mostly made up of combinedavailable chlorine (CAC)

K Superchlorinate. MaintainFAC and combined availablechlorine (CAC) atrecommended concentrations.

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ATHLETE’S FOOT � Fungus on pool decks, changeroom and shower floors

K Exclude people with athlete’sfoot from pool, disinfect.

CARBONATEPRECIPITATE• scale/cloudy/reside

� High pH and total alkalinity K Maintain pH of 7.2 to 7.4 untiltotal alkalinity decreases to 80ppm. Raise calcium hardnessto obtain “balanced” water.

CHLORINECONSUMPTION HIGH

� Heavy bather load, high dirtload, heavy rain or wind storms

K Superchlorinate

� Low stabilizer level K Add stabilizer (outdoor poolsonly!)

CHLORINE RESIDUALTOO HIGH

� Chlorine demand has droppedexceeds feed rate

K Turn off chlorinatorK DilutionK AerationK SunlightK Addition of dechlorinating

agents

� Excessive stabilizer level K Dilution

CHLORINE RESIDUALLOW

� Rate of feed too low K Boost rate of feed

� Demand above normal due toheavy swimming load, hotsunny weather, algae, debrisblows into pool - leaves, etc.

K If chlorinator capacity is notsufficient, supplement chlorinefeed by hand dosage ofhypochlorites.

� Corrosion or plugging ofchlorination system

K Shut off chlorine unit andcheck.

� Low stabilizer level K Increase stabilizer level to 50ppm cyanuric acid (outdoorpools only!)

CHLORINE ODOUR,SWIMMER’S EYE ANDSKIN IRRITATION

� CAC too high K Superchlorinate to reduceCAC.

K If chronic, install ozone system(corona discharge).

K Dilution

� Improper pH K Adjust pH

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CLOUDY WATER � High CAC K Superchlorinate.

� pH too high K Lower pH.

� Total alkalinity too high K Reduce until balanced.

� Calcium hardness too high K Lower until balanced.

� Extremely small particles inpool water caused by storm,etc.

K Floc sand with clear-aid oralum.

� Poor circulation in certain areas K Readjust directional ball inlets

� Excessive total dissolved solids(TDS)

K DilutionK Drain and fill

� In pools using diatomite filters,it is usually due todiatomaceous earth in the pool. Faulty precoat procedures tobroken or torn elements are theusual cause.

K Check and/or repair filterelements.

K Check and adjust precoatprocedures.

� Improper application of non-chlorine shock treatmentchemicals

K Follow manufacturer’sinstructions.

K Use calcium hypochlorite.

CLOUDY RED-BROWNWATER

� This is usually due toprecipitated iron.

K The precipitate can be settledand vacuumed or filtered fromwater. The filters will have tobe turned off. In extremecases, the settling process canbe aided by adding alum to thepool surface. Allow the alumto settle quietly overnight. Ensure the pH of the water isabove 7.6 before using alum. Check the manufacturer’sinstructions when using alum.

COLOURED WATER -BROWN, BLUE, BLACK(usually after initial fillingof pool)

� Metallic ions in the water;brown is iron, blue is copper,black is manganese.

K Increase pH to 7.8 and vacuumthe precipitate off the poolbottom to the waste line.

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COLOURED WATER -GREEN

� Algae bloom K Superchlorinate. Maintain adadequate free availablechlorine (FAC).

� Dissolved iron K Superchlorination will convertdissolved iron to a red-brownprecipitate which can bevacuumed.

� Over stabilization K Dilution

� Improper use of bromine K Dilution

COLOURED WATER -MURKY BROWN

� Insufficient backwashing K Backwash

� Inadequate filter run K Increase the filter run.

� Channels in filter run K Increase the backwashing time.K Increase the backwashing rate.K Add decalcification chemical.K Change the sand.

CORROSIVE WATER• corroded/stained

fixtures• pump/heater pipe

corrosion

� Low pH K Maintain pH at 7.4 to 7.5

� Low total alkalinity K Increase total alkalinity to 80 -120 ppm.

FOULED POOL � Fouled by vomit and/or feces a) Clear the pool of bathersb) Stop the recirculating pump

and shut off the chemicalfeeders.

c) Remove the offending matterby use of a leaf skimmer,handheld scoop, etc.

d) Vacuum with dischargedirected to the sewer. Discharge approximately 5%of the water to the sewer.

e) Superchlorinate the pool to 10ppm chlorine.

f) Clean the deck and equipment. Use a strong chlorine solution.

For greater details -seeAppendix #4

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GREEN HAIR � Results from copper ions in thewater by an overdose ofcopped-based algaecides.

K Discontinue use of copper-base algaecides and maintainproper pH to prevent corrosionof copper pipes in the system.

K Drain portion of pool volumeand fill with fresh water.

pH DIFFICULT TOREAD

� High free chlorine dosage fadesor changes colour produced insample.

K Wait until free chlorine lowersor add sodium thiosulphate(available from pool supplier)to sample before running pHtest.

� Tube and cap are dirty K Clean tubes and capsthoroughly; rinse using poolwater.

� pH less than 6.8 or greater than8.2

K Adjust pH to swimming poolrange (i.e. 7.2 to 7.8).

pH DROPPING � Acidic disinfectants� Heavy bathing load

K Add soda ash (Na2CO3)

pH FLUCTUATING � Low total alkalinity K Have total alkalinity tested.K Add sodium bicarbonate

(NaHCO3)

pH HIGH � Algae (tends to raise pH)

� pH adjustment too high

K Superchlorinate and adjust pH

K Lower pH

� Hypochlorite disinfectant K Lower pH

pH LOW � pH/chlorine dosages incorrect K Raise pH

SAND IN POOL � Failure of filter underdrainsystem

K Remove filter sand, check andreplace underdrains asnecessary.

� Filter sand grain sizeinadequate

K Filter sand should meetmanufacturer’s specifications.

SCALE FORMATIONON POOL WALLS OREQUIPMENT

� pH too high� Total alkalinity too high� Calcium hardness too high

K Balance pool water accordingto Langelier’s saturation index

SCUM ON POOLWALLS

� Inadequate skimming K Check float weir, increaseflow rate through skimmers. Scrub pool walls.

� Body oils and cosmetic lotionsused by swimmers

K Shower with soap and warmwater before entering pool. Recommend bathing caps beworn. Scrub pool walls.

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SLIPPERY POOLDECKS

� Algae growth K Clean with 100 ppmhypochlorite solution. Letstand, then rinse areathoroughly. Repeat withstronger solution if necessary.

TURBIDITY � Insufficient back washing K Backwash

� Poor floc on filter sand K Add alum. Checkmanufacturer’s instructions.

� Windblown dust K More vacuuming - cover when closed

- increase turnover rate

� Poor re-circulation K Maintain design flow rate andcheck filter’s backwash moreoften if necessary.

� Iron in suspension a) Add make-up water throughfilter

b) Flush supply and make-uplines occasionally.

c) Add alum to the entire poolsurface and let settle. Vacuumprecipitate to waste. Checkmanufacturer’s instructions.

WHITE RING AROUNDTHE WATER LEVELTILE

� Calcium salts in hard water,high pH

K Lower pH with sodiumbisulphate or muriatic acid

K Maintain pH level of 7.2 - 7.8

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SECTION 6: WHEN TO CLOSE A POOL

1. Pool contaminated with fecal material and/or vomitus.

2. Pool water is cloudy and the bottom drain cannot be seen from the pool deck.

3. Chemical Imbalance.

• If the pool water chemistry becomes imbalanced to a point that minor adjustmentscannot correct it, and a significant amount of chemical must be added, it will benecessary to close the pool.

4. Unsatisfactory bacteriological tests.

- repeat sample confirms the presence of E. coli ;*

- repeat sample confirms presence of greater than 50 Staphylococcus aureus per 100 mlsample*

- repeat sample confirms the presence of greater than 50 Pseudomonas aeruginosa per100 ml sample*

* Refer to Guidelines for Applying Public Pool Bacteriological Standards details.

5. Pool has no disinfectant residual (free available chlorine or total bromine).

6. Mechanical Failure

• Improperly working filters and pumps will not be able to effectively do their job.

Pool operators must always inform the EHO of the Government Service Centre (GSC) oftheir pool closure. The EHO must immediately inform the Health and Community ServicesBoard of any pool closure.

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SECTION 7: REFERENCES

1. City of Winnipeg - Community Services Department (Environmental Health Services), “PoolSafe - Level 1, Swimming Pool and Whirlpool Operator’s Handbook”, Third Edition,1995

2. Dr. Lowry, “Lowry’s School of Pool and Spa Maintenance - Level 1 Workbook”, 1995

3. Health and Welfare Canada - Environmental Health Directorate (Health Protection Branch),“Swimming Pool Water Quality”, November 1978

4. Ontario Ministry of Health, “Recommended Standards for the Operation of Public Spas”,1989

5. City of Scarborough Health Department, “Seminar for Lifeguards and Public PoolOperators”

6. NS Department of Health, “Guidelines for Swimming Pools”

7. PEI Department of Health and Social Services, “A Guide to Swimming Pool Policies andProcedures on Prince Edward Island”

8. Northern Light Regional Health Services, “Pool Operators Course”

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SECTION 8: APPENDICES

APPENDIX 1: WATER QUALITY REQUIREMENTS FOR VARIOUS CLASSES OFPUBLIC POOLS

Parameter/Standard Class of Pool Type of Pool

Indoor Outdoor

pH A, B, & C (All Classes)

7.2 - 7.8 7.2 - 7.8

Total Alkalinity A, B, & C (All Classes)

80 - 120 ppm 80 - 120 ppm

Hardness A, B, & C (All Classes)

200 - 300 ppm 200 - 300 ppm

Disinfectant:

1. Chlorine (Free AvailableChlorine)

2. Total Bromine

a) All public poolsexcept Class B:spa/ whirlpooltypes of pools

b) Class B: spa/whirlpool types ofpools

a) All public poolsclasses exceptClass B:spa/whirlpool typesof pools


1.5 (minimum acceptablelimit 0.5 ppm)

2 - 3 ppm

2 - 3 ppm

2 - 4 ppm

3 ppm (minimum acceptablelimit 1.0 ppm)

2 - 3 ppm

2 - 3 ppm

2 - 4 ppm

Stabilizer - CyanuricAcid

A, B, & C (All Classes)

Not Applicable 25 - 50 ppm

Water Temperature a) All public poolsclasses exceptClass B:spa/whirlpool typesof pools


21°C - 32°C

36°C - 38°C

21°C - 32°C

36°C - 38°C

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Parameter/Standard Class of Pool Type of Pool

Indoor Outdoor

E. coli A, B, & C (All Classes)

0 per 100 ml ofsample

0 per 100 ml ofsample

Staphylococcusaureus


50 or fewer per 100ml of sample

50 or lower per 100ml of sample

Pseudomonasaeruginosa


10 or fewerper 100 ml of sample

10 or lessper 100 ml of sample

Standard PlateCount


250 or fewer per 1 mlof sample

250 or lower per 1 mlof sample

Signature of Recording Person

FORM A DAILY RECORD OF OPERATION Appendix 2(For use in all Public Pools exceptClass B: whirlpool, spa, types of pools) *ppm - parts per million

NAME OF POOL LOCATION OPERATOR & TELEPHONE NO. DATE DAY

HOURLY WATER TESTS

TEST ½ HOUR BEFOREOPENINGTIME:

4 HOURS AFTEROPENING




TIME: No. ofBathers

TIME: No. ofBathers

TIME: No. ofBathers

TIME: No. ofBathers

Free Available Chlorine Residual (Ifchlorine is used as a sanitizer) ppm*

Total Chlorine Residual (If chlorineis used as disinfectant) ppm

Total Bromine Residual (If bromineis used as disinfectant) ppm

pH

DAILY TEST

WATER TEMPERATURE °C

WEEKLY TESTS TO BE PERFORMED EVERY MONDAY

TOTAL ALKALINITY ppm

STABILIZER (CYANURIC ACID)CONCENTRATION - USED INOUTDOOR POOLS ONLY

ppmHARDNESS

ppm

COMMENTS (ITEMS OF NOTE)

NOTE: KEEP THIS RECORD FOR ONE YEAR FROM DATE OF THE RECORD

Signature of Recording Person

FORM B DAILY RECORD OF OPERATION Appendix 3(For use in all Class B: whirlpools, spas, natural hot water pool,roman bath, hydro-swivel or hyrdo-therapy pool) *ppm - parts per million

NAME OF POOL LOCATION OPERATOR & TELEPHONE NO. DATE DAY

HOURLY WATER TESTS

TEST ½ HOUR BEFOREOPENINGTIME:





TIME: No. ofBathers

TIME: No. ofBathers

TIME: No. ofBathers

TIME: No. ofBathers

Free Available Chlorine Residual (Ifchlorine is used as disinfectant) ppm*

Total Chlorine Residual (If chlorineis used as disinfectant) ppm

Total Bromine Residual (If bromineis used as disinfectant) ppm

pH

Water Temperature °C

DAILY TESTS

TOTAL ALKALINITY ppm

STABILIZER (CYANURIC ACID)CONCENTRATION - USED INOUTDOOR POOLS ONLY

ppm

WEEKLY TEST TO BE PERFORMED EVERY MONDAY

HARDNESS ppm

COMMENTS (ITEMS OF NOTE)

NOTE: KEEP THIS RECORD FOR ONE YEAR FROM DATE OF THE RECORD

APPENDIX 4: CLEANING AND DISINFECTING POOLS CONTAMINATED WITHFECAL MATERIAL AND/OR VOMITUS

Procedures for all Public Pools Classes Except B: Whirlpool, Spa Types of Pools

A. Pools Contaminated With Fecal Material - Normal Formed Stools

Step 1 When fecal material is noticed in the pool, immediately evacuate everyone from the pool.

Step 2 Remove the fecal material from the pool by using a scooping device and dispose of thestools into a toilet. Clean and disinfect the scooping device.

Step 3 Superchlorinate the contaminated area of the pool to at least 10 ppm free availablechlorine for a minimum of 15 minutes.

Step 4 Reduce the free available chlorine of the pool water to 1.0 - 3.0 ppm prior topermitting patrons back into the pool.

B. Pools Contaminated With Diarrhoea or Vomit

Step 1 When diarrhoea or vomit is observed, immediately evacuate all patrons from the pool.

Step 2 If possible, identify the person responsible for the accident and request that theyimmediately go to their doctor. Ask for their name and telephone number.

Step 3 Shut off the re-circulation pump and other chemical feeders.

Step 4 Remove vomit and any visible diarrhoea with a scooping device and dispose of thematerial into a toilet. Clean and disinfect the scooping device.

Step 5 Vacuum to waste any remaining diarrhoea or vomit.

Step 6 Superchlorinate the pool to a minimum concentration of 50 ppm for two and a halfhours or to a minimum concentration of 80 ppm for one and a half hours.

Step 7 Turn on the re-circulation equipment and chemical feeders.

Step 8 Reduce the free available chlorine of the pool water to 1.0 to 3.0 ppm prior topermitting patrons back into the pool.

Procedures for Class B: Whirlpool, Spa Types of Pools

Step 1 Close the pool.

Step 2 If necessary, remove any fecal material or vomit with a scooping device and dispose ofthe material into a toilet. Clean and disinfect the scooping device.

Step 3 Turn the heater off. Wait until the heater unit has cooled.

Step 4 Drain the pool. Use protective rubber gloves and a face mask when working aroundthe tank and mechanical equipment.

Step 5 Ensure that the pool area is well ventilated.

Step 6 Clean the pool basin with a mild tub and liner cleaner. Ensure that all grease and scumhas been removed. Rinse the cleaner to drain.

Step 7 Fill the pool to the halfway point of the skimmer mouth ensuring that the air lines ofthe hydro jets are flooded.

Step 8 Shock the water with a chlorine residual of 50 ppm. *Refer to the manufacturer’sinstructions for the amount of chlorine required to obtain 50 ppm.

Step 9 Turn off all equipment that functions when the filter pump is on (i.e. chemical feeders,pH controller and other chemical controllers).

Step 10 Turn the filter pump on and circulate for a minimum of two and a half hours.

Step 11 Turn the hydro jet pump on for a minimum of 20 minutes.

Step 12 Disinfect the deck area surrounding the pool with a 100 ppm chlorine solution or a 200ppm quaternary ammonia compound solution.

Step 13 At the end of two and a half hours, backwash the filter according to the manufacturer’srequirements.

Step 14 Drain the pool and hydro jet lines.

Step 15 Refill the pool and immediately repeat backwashing the filter.

Step 16 Top up the pool water level and turn on any equipment which functions with the filterpump.

Step 17 Balance the water chemistry by using an approved test kit. A Langelier index betweenplus 0.3 and minus 0.3 is acceptable. 0.0 is optimum.

Step 18 Maintain the required disinfectant level. A free available chlorine residual of 2 ppm to3 ppm or a total bromine residual of 2 to 4 ppm is recommended. Do not exceed acombined available chlorine residual of 0.5 ppm.

APPENDIX 5: GLOSSARY

ACIDA chemical compound which releases hydrogen ions in a water solution.

ALGAEPlant life of many colours which grows in water in the presence of sunlight and carbondioxide. In swimming pools it produces slippery spots and cloudy, uninviting water.

ALGICIDEA chemical which will kill algae.

ALGISTATA chemical which inhibits growth of algae.

ALKALINITYThe amount of bicarbonate, carbonate, or hydroxide compounds present in a water solution. Total alkalinity is a measure of the buffering capacity of water against rapid pH change.

ALUMAn aluminum compound applied in pools to produce a gelatinous floc in sand filters, or tocoagulate and precipitate suspended particles out of solution.

AMMONIAA chemical compound that contains nitrogen and hydrogen that combines with free chlorinein pools to form chloramines or combined available chlorine.

APPURTENANCESAccessory objects or parts.

BACKWASHReversing the flow of water through a sand filter for the purpose of cleaning it.

BASEA chemical which neutralizes acids by releasing hydroxyl ions in a water solution. Achemical which raises the pH when added to swimming pool water. Examples of bases aresodium carbonate (soda ash) and sodium hydroxide (caustic soda commonly known as lye).

BACTERIASingle-celled microorganisms. Some bacteria are beneficial yet many others are capable ofcausing disease.

BREAKPOINTThe process of adding chlorine to pool water in large doses to oxidize organic material anddestroy chloramines.

BROMAMINESHypobromous Acid (HOBr) combined with ammonia products. Bromamines have nonoticeable odour, do not cause eye irritation and have equal disinfecting power as HOBr.

BUFFERA chemical when dissolved in swimming pool water will resist pH change. Sodiumbicarbonate (NaHCO3) is this type of chemical.

CALCIUM HYPOCHLORITEA compound of chlorine and calcium used in white granular form as a disinfectant in pools. In water solution it releases 65% to 70% of its weight as available chlorine. Calciumhypochlorite must be handled with care.

CHLORAMINESCompounds that are produced when ammonia compounds react with FAC. Chloraminesproduce the obnoxious chlorine odours associated with pools and greatly reduces thedisinfecting power of chlorine. Chloramines may also cause skin, eye and respiratoryirritations.

CHLORINEUsed in swimming pools as a disinfectant and algicide. Extreme caution must be used whenhandling. Available in the inorganic form as gas, liquid, and hypochlorite and in the organicform of chlorinated cyanurates.

CHLORINE DEMANDThe amount of chlorine required to destroy infectious agents, algae and/or other organic andinorganic material in water before an available chlorine residual can be achieved.

CLARITYThe state of clearness of pool water which can be demonstrated by how easily and clearly anobject can be seen in a given depth of water. A good test for clarity is the ability to see themain drain cover from anywhere on the pool deck.

COLIFORM ORGANISMSBacteria found in the intestines of warm-blooded animals. Their presence in pool waterindicate the possibility of the presence of disease-causing bacteria.

COMBINED AVAILABLE CHLORINE (CAC)See definition of chloramines.

CONTAMINATEDImpure. Can refer to the presence of harmful infectious agents in water, or to the presence ofany unwanted substance.

CYANURIC ACIDA chemical that combines with available chlorine in pool water to prevent rapid loss ofchlorine due to ultraviolet radiation from sunlight.

CYSTAn infectious parasitic stage, which has a thick outer wall making disinfection of pool waterdifficult.

DIATOMACEOUS EARTH (DE)A white porous powder used as a filter media composed of fossilized skeletons of one-celledorganisms called diatoms.

DIATOMACEOUS EARTH FILTERA vacuum or pressure filter designed to use DE as a filter media.

DIATOMITECommon name for diatomaceous earth.

DISINFECTANTA chemical which will destroy infectious agents.

DOWNWASHThe process of removing debris from pipes after backwashing filters. This backwash effluentis drained to waste before beginning a new filter run.

EFFLUENTThe outflow of water from a filter, a pump or a pool.

FILTER ELEMENTThe part of a diatomite filter, usually made of cloth, wire screen or other fine mesh material,which collects diatomaceous earth for filtration purposes.

FOLLICULITISAn infection of hair follicles of the body which can be caused by Pseudomonas bacteria.

FILTER RATEThe volume of water which passes over a filter surface area during a given period of time. Thefilter rate is commonly expressed in litres per minute per metre squared (Litres/minute/m2).

FILTER RUNThe operational time of a filter between backwashes.

FILTER SANDA filter medium found in sand filters composed of hard, sharp silica, quartz, or similar particlewith proper grading for size and uniformity.

FLOCCULENTA compound used with sand filters to form a thin gelatinous layer called floc on the top of thesand. The floc produces aids in trapping fine suspended particles which might normally passthrough the sand medium.

FLOW RATEThe volume of water which flows past any point in the recirculation system during a givenperiod of time. Flow rate is usually expressed in litres per minute (LPM).

FREE AVAILABLE CHLORINE (FAC)The concentration (ppm) of chlorine in swimming pool/whirlpool water that is ready andavailable for disinfection.

GUTTEROverflow trough located at the edge of a pool. Designed for continuous removal of surfacewater and floating debris from a pool.

HARDNESSRefers to calcium and other dissolved minerals including magnesium which may cause scalebuild-up in the recirculation equipment.

HYDROCHLORIC ACIDAlso called MURIATIC ACID when diluted. A strong acid used to lower pH, lower totalalkalinity and occasionally used for cleaning purposes.Caution: Use extreme care and protective equipment when handling.

HYDROGEN ION (H+)The positively charged nucleus of a hydrogen atom. Its’ presence in water solution is used as ameasure of acidity of the solution.

HYPOBROMOUS ACID (HOBr)A disinfectant that is formed when bromine products are added to water.

HYPOCHLORINATORAn adjustable chemical feeder which feeds liquid chlorine solutions into the pool water at agiven rate.

HYPOCHLOROUS ACID (HOCl)A very effective disinfectant, oxidant and algicide.

IMPELLERThe rotating vanes of a centrifugal pump.

INFECTIOUS AGENTSHarmful microorganisms that are capable of causing disease. They include bacteria, viruses,fungi and protozoa.

INFLUENTWater flowing into a pool, a pump, a filter, a chemical feeder, or other equipment.

LIFELINEA rope line across a pool to designate a change in slope in the pool bottom, or the beginning ofdeep water. It is usually supported by regularly spaced floats.

LINT STRAINERA basket located at the pump influent line used to screen out lint and other debris which mightcause damage to the pump.

LIQUID CHLORINEIn swimming pool terminology, sodium hypochlorite (NaOCl) solutions are known as liquidchlorine.

MACROCONIDIAA network of microscopic plant life fibres that contain fungal spores.

MURIATIC ACIDA dilute solution of hydrochloric acid.

ODOURSUsually the result of chloramines or sulphur in water.

OOCYSTAn infectious parasitic stage of Cryptosporidium protozoa. An oocyst has a thick andenvironmentally resistant outer wall that makes disinfection very difficult.

OPEN SORESNon-intact skin associated with drainage, i.e. a wet sore.

ORGANIC BROMINEA disinfectant in the form of small, white, slow-dissolving pucks.

OVERSTABILIZED POOL WATERA condition resulting from adding too much cyanuric acid to pool/whirlpool water. Overstabilized pool water reduces the disinfecting power of chlorine and is usually greenish incolour.

OZONE (O3)Used in swimming pools/whirlpools to OXIDIZE organic contaminants.

pHThe logarithm of the reciprocal of the hydrogen ion concentration of water solution. Ameasure of the balance between acidity and basicity (alkaline qualities) of a solution. A pHbelow 7.0 is considered acidic. A pH of 7.0 is considered neutral. A pH above 7.0 isconsidered alkaline.

PHENOL REDAn organic dye which is yellow at a pH of 6.8 and turns progressively deeper red in colour asthe pH increases to 8.4. The most commonly used test reagent for pH in pools.

ppmParts per million or milligrams per litre.

PRECIPITATEAny compound which comes out of solution as a chemical reaction and remains insoluble (i.e.calcium carbonate).

PRECOATThe layer of diatomaceous earth deposited on filter septums at the start of a filter run.

SAND FILTERA pool filter using sand, or sand and gravel as a filter medium.

SCALEThe mineral deposits or precipitant, usually calcium carbonate, caused by hard water, on thefloors, walls, metal piping, filter system, etc., which can become unsightly and may interferewith the proper operation of the pool.

SKIMMERA part of the recirculation system which continuously removes surface water and floatingdebris from a pool.

SKIMMER WEIRThe part of a skimmer which assures a continuous flow of water to the skimmer and whichprevents oils and debris from returning back to the pool.

SODIUM BICARBONATE (NaHCO3)Baking soda. Very effective in alkalinity control. Sodium bicarbonate increases the alkalinityrapidly and the pH less rapidly.

SODIUM CARBONATE (Na2 CO3)Soda ash, used to raise pH and slightly increase total alkalinity in pool water.

SODIUM HYPOCHLORITE (NaOCl)A liquid chlorine solution containing 12% to 15% available chlorine.

SODIUM THIOSULPHATEA chemical solution used to neutralize chlorine from a test sample to avoid false pH testreadings, or false bacteria test results. If used correctly, sodium thiosulphate can also lowerchlorine concentrations in swimming pool/whirlpool water.

SPORESSingle-celled resistant bodies produced by fungi.

TITRATIONA method of testing for total alkalinity, hardness, etc. Also for making determinations as tothe amount of acid which may be safely added to lower pH.

TOTAL ALKALINITYSee Alkalinity.

TOTAL AVAILABLE CHLORINE (T.A.C.)Is equal to the free available chlorine plus combined available chlorine.

TOTAL BROMINE RESIDUALHypobromous Acid (HOBr) + Bromamines

TURBIDITYThe quantity of suspended particles in pool water that leads to cloudiness.

TURNOVER RATEThe number of times a quantity of water equal to the total capacity of the pool passes throughthe filters in a stated time. Usually referred to as turnovers per day.

UNDERDRAIN (COLLECTION MANIFOLD)The piping system located at the bottom of a sand filter which collects the filtered water duringa filter run, and distributes the backwash water during backwashing.

VACUUM FILTERDiatomite filter located before the pump in a recirculation system. Water is drawn through thefilter rather than being pushed causing a vacuum.

VOIDSAreas between particles or fibres of a filtering medium which determines the permeability andthe dirt holding capacity of the filter.

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