Chapter 14: Swimming Pools and Recreational Facilities
Ozone
The use of _______ for swimming pool water disinfection is gaining acceptability as a supplemental process and is used typically under restrictive applications in swimming pools because of the lack of residual effect. It is a gas that has considerable destructive potential when released into the air in the equipment room
Langelier Saturation Index
The use of the _______ ______ _______ is an effective way of fighting corrosion and scale damage to the pool and its equipment.
Calcium and Sodium hypochlorination
These 2 forms of chlorine are manufactured by combining a alkali with chlorine to form a hypochlorite.
Cartridge Filters
These filters are primarily recommended for use on indoor pools, for facilities of less than 80,000 gallons with a designed recommended filtration rate that does not exceed 0.15 gpm, and with the requirement that extra filter cartridges be on hand at all times
Spray Pools
These pools spray fresh, or disinfected, recirculated water over the play area. This is considered the preferable public health option
Brominator
This device is a simple unit in which fresh or recirculated water is introduced into a bromine jar ar atmospheric pressure to form a solution that is conveyed into the pool
Positive Displacement chemical feed pump
This diaphragm or piston pump is the preferred method of hypochlorination because it delivers a measured amount of hypochlorite through a two-valve pump chamber.
Siphon Feeder
this device depends on reduced pressure created by passing a stream of water through a constriction to siphon hypochlorite into the water stream at the constriction.
excess
An _______ level of hardness results in scale formations, discoloration, rough plaster, hard-to-clean surfaces, and reduction in recirculation efficiency.
bactericides slower
Chloramines are _______, but the rate of disinfection is on the order of 60 to 100 times _______ than that of free chlorine.
1.0 1.5 above hair
A disinfectant is most effective when a free chlorine level of between ______ and ______ ppm is maintained. Levels _______ 2.0 ppm have been found to cause shifts in some _____ coloring.
Pool Filters Polish
A good _______ _______ should easily remove all particles larger than ten micrometers. However, the purpose of the filter is not to remove bacteria or viruses, but to clarify and _______ the water.
Ultraviolet Light
A technique using _______ _______ is gaining acceptance also as a supplemental treatment process for disinfection. This teqnique is sensitive to any water turbidity that restricts its bactericidal impacts.
oxidized ammonia combined chlorine
After the chlorine in hypochlorous acid has _______ organic matter and some inorganic substances, it reacts with ______ to form compounds called chloramines. This combination of chlorine and ammonia is called "_______ ________."
basic solutions
Alkaline compounds are those which produce _____ _____ when ionized.
base exchange sodium
An easier way is to soften the water through a ______-_______ that replaces the calcium and magnesium with ______.
Manhole gate valves Air relief valve
Both sand filters should be equipped with a cleaning port or ________ for cleanout, _____ _____ on the inlet and outlet for flow control, an _____ _______ _______for removing accumulated gas at the top of the filter shell and an indirect discharge to waste on the line used for backwashing the filter.
Residual Levels
Chorine ________ ________ are typically tested in the field using the _______ method. This method uses standarized tablet reagents containing diethyl-p-phenylene diamine indicators.
Spas 3.0-5.0
Free chlorine for spas: min 2.0, ideal ___-___ with a max of 10.0 ppm
Stabilized Chlorine
Free chlorine, when combined with cyanuric acid, is called "_______" _______.
Iron Calcium Magnesium Sedimentation Filtration
Hard water can be softened by a treatment that changes ________, ________, & _______compounds from a soluble to an insoluble form and then removes the material by _______ & _______.
Pressure Solution Feeder (Alum Pot)
Heavy metal or plastic pots are connected to the water flow by small feed lines across an orifice plate installed in the main flow pipe.
scale cloudy hydrogen ions
High pH (above 7.6) may cause _______ formation, eye irritation, and _____ water. High pH may also redue the available chlorine and increase the number of _____ _____.
Gas Chlorine
In general, pools over 150,000 gallon capacity can operate more economically with ______ _______ than with other types of chlorination.
Fast Flow-Through Pools
In these pools the water is less than 2 feet deep and treated, and disinfected water flows through the system every 20 minutes
7.2 to 7.6
It is important that the disinfectant levels and records of disinfectant levels be maintained, and the pH be kept within the ____ ____ _____ range at all times.
Fill and Draw Pools
Like a community bathtub, this pool is filled with water and drained after use. This type of pool is not acceptable for use due to rapid contamination and the resultant health risk.
Chlorine corrosion eye
Low pH (below 7) may result in faster _______ loss, easier formation of chloramines, _______ of equipment, damage to plaster, and _____ irratation.
10
Most states require a minimum ____ft of depth under a board 4 ft or less above the pool water with a side clearance of 8 ft on each side, 6 feet behind and 20 ft in front of the pool.
Gravity Sand Filters
Once of considerable popularity for large pools, _____ _____ _____ are seldom used today due to the significant cost, skills required for proper operation, and the large space requirements.
Turned off 24
One frequent misconception of pool operators is that the recirculation equipment can be _____ ______ after hours. To the contrary, the pool equipment must be operated ____ hours per day to ensure appropriate disinfection levels and water quality.
Diving Boards 20
Standard _____ _____ are mounted 1 meter (3') and 3 meters (10') above the pool water. The boards are 16 feet long by ___ inches wide and should extend a minimum of 6 feet beyond the pool wall.
feeding disposal
The DE filter requires more attention than the sand filter, namely, continuous _____ and _____ in compliance with state and local reguations.
Water Treatment Equipment
The _____ ______ _____, with the pump sized to recirculate the pool water (typically every 6 hours), the pool filter sized to handle the gallons per minute delivered by the pool pump, a disinfection system capable of keeping the pool free of bacteria when the pool is being used to capacity , and a pH control chemical feeder.
Alkalinity
The _____ should be at 80 to 120 ppm of calcium carbonate.
Flow Meter Water
The ______ _______ should also be located on a straight section of pipe in strict accordance with the manufacturers specifications or the _______ turbulance will produce errors in flow rates.
Pool Structure
The _______ ______, with its main drain for collecting settling solids from the bottom, skimmers or gutters for cleaning the water's surface, and the return waterlines positioned to ensure total water circulation.
Rapid Rate
The _______ _______ filter operates at a maximum filter rate of 3 gallons per minute per square foot
High Rate
The _______ _______sand filter operates at a recommended maximum filter loading rate ranging from 12 to 20 gallons per minute (gpm) per square foot depending upon filter manufacturer and state rules.
Cartridge 30
The _______ filter is the most popular filter system in use for spas and hot tubs, The pumps should provide a turnover rate of ____ minutes
Backwash discharged
The _______ process involves the running of water through the sand from the bottom up to remove materials caught by the sand in the filtering process. This wastewater must then be ______ to an approved treatment system.
Cyanurate
The concentration of ________ should be held at approximately 50 to 60 ppm. The suggested upper limit is 100 ppm.
Water Quality
The current ______ ______, with the desired disinfectant level, proper pH, a good balance of hardness and alkalinity, clear water, no grease line around the fool, and water that is free of floating and bottom sediment.
Sizing pumps
The formula for _______ _______ is as follows: Horsepower=(gallonsper minutes)(head in feet)(3960)(pumping efficiency)
Turnover Rate
The formula for calculation of the current _____ _____ of a pool is as follows: Turnover Rate =(pool capacity in gallons) / (flow meter reading (gpm)(60)
sunlight wind Stabilizers
The free pool chlorine is often lost to dissipation due to strong ________ & ________, making it hard to maintain the required minimum residuals. _______ such as chlorinated isocyanurates are often used to minimize this impact. However, the cyanuric acid levels can build up to levels not acceptable to the health authority.
Calcium Chloride (CaCl2)
The level of hardness can be raised through the addition of _______ _______ to the pool water. The CaCl2 must be added to the _______, not the water to the CaCl2.
sodium bicarbonate sodium bisulfate muriatic acid
The most effective way of raising total alkalinity without great effect on pH is to add _____ _____ (baking soda). The pH can be lowered most effectively by repeated small doses of _______ _______ or _______ _______.
Sand Diatomaceous Earth Cartridge
The primary types of pool filters are the _____, ______ _____, and _____.
Pool Structure Water Treatment Equipment Water Quality Sanitation, Health, & Safety Issues
The public swimming pool typically has four main areas of interest to the environmental health specialist:
Pool gutter or skimmer
The purpose of a _______ _______ or _______ is to remove the floating material from the pool
Spray Pools Fast flow-through pools Fill and Draw pools
The standard Wading pools come in three forms.
Total Residual Chlorine
The total concentration of residual "free chlorine" plus the residual of "combined chlorine" is called "______ _______ ________."
Contact Pot
This is a pot filled with liquid bromine and placed in a closed pressure system on a bypass line from the pump discharge. The water flows through the pot, dissolves bromine, and carries it into the pool.
Sodium bisulfate chlorine sodium calcium
To lower the pH, _______ _______ or muriatic acid (weakened form of HCL) can be used. Gaseous _______ lowers pH drastically; _______ and _______ hypochlorite raise pH moderately; most other disinfectants have little effect on pH levels.
chlorine disinfectant 2.0-4.0
To provide maximum protection to swimmers the levels of _____ _____ should be maintained at free chlorine for pools and waterparks: min 1.0, ideal ___-___, max 5.0 ppm
Alkalinity
Total _______ should be maintained between 120 and 150 ppm.
Too little
Water with _____ ______ hardness etches plaster, increases corrosion, damages pool liners, and erodes pump impellers.
pressure Chlorinator
When a tank of liquid chlorine has its _______ removed, it becomes a gas. The liquid chlorine feeder or ________ is a device that can control the change of liquid into gas, dissolve the chlorine gas in water, and proportion the chlorine solution to the main flow of water.
bacteria free standards undesirable eye odors
When chloramines are allowed to exist, the water can be held to satisfactory _______ _____ ______ by maintaing the total residual chlorine at a concentration of 2.0 to 2.5 ppm. This practice is _______, however, because the chloramines cause _____ irritation and produce objectionable "chlorine" _____.
Breakpoint Chlorination rise nitrogen drops breakpoint Superchlorination
When chlorine is added to water containing ammonia, it reacts with the ammonia to form chloramines. If more chlorine is added to the water, the total residual chlorine continues to ____ until the concentration reaches a point that rapidly forces the reaction with ammonia to completion. Compounds of ______ and chlorine are released from the water, and the apparent residual chlorine decreases. The point at which the residual suddenly _____ is called the _______. _________ usually results in exceeding the breakpoint.
Calcium Hypochlorite
_____ _____, which comes as a solid (powdered) material, is available commercially in varying strengths of available chlorine from 70% on down.
Bathing load Pool Volume
_______ ______ and _____ _______ should be considered together to determine the size of the filtration plant and choice of water treatment system
Cartridge Filters
_______ _______ are increasing in popularity due to reduced space, maintenance and operational requirements.
Diatomaceous Earth (DE)
_______ _______ filters use a media that is compromised of microscpic marine plants spread in a thin coat over filter bags or septa.
Turnover Rate
_______ _______ is the term used to describe the time it takes to filter the entire contents of the pool. The requirements for a pool are state specific.
Pseudomonas Cryptosporidium
_______ and _______ are two of the organisms of considerable concern today. Other organisms and diseases invlude E.coli, legionnella, pnemophila, streptococcus, staphylococcus, naegleria fowleri, polio, giardiasis, leptospirosis, schistosomiasis, impetigo, ringworm, and other fungus infections.
Bromine safer burn
_______ is not as volatile as chlorine and is often used in spas. It is also available in solid organic complex form that is ______ to handle, though more expensive. Since it will ______ the skin, it should be stored in recessed floor or wall-hung units to prevent accidentally tipping the bottles.
Hardness
_______ is the measure of the mineral content of water.
Calcium
_______ is usually 70% of the total hardness reading, with the remainder being magnesium. Aluminum & Iron also contribute to water hardness.
Iodine
_______ or iodine released by chlorine (as from sodium or potassium iodode) are 2 means used for disinfecting swimming pool waters
Chlorine solid liquid gas strength
_______ remains the leading disinfection process for pools. It is available as a _____, _____, & _______, and the age of the solution greatly affects its _______.
Sanitation, health, and safety issues
_______, ______, _____ _______ _______ around the pool and bathhouse that require clean, non cluttered pool decks, an appropriate safety list, safety equipment, safety showers and soap dispensers, clean towels, cleaned and disinfected floors, and good supervision.
Sodium Hypochlorite
________ ________ (common household bleach), which comes in a liquid solution form, is available commercially in varying strengths of available chlorine from about 4 percent to 12 percent.
Air controlled suction feeder
a jar of liquid hypochlorite solution is directly connected into the suction side of the recirculation pump, and flow is controled by an air metering device that lets air into the jar to replace the solution that is withdrawn
Ionized Silver
is used in a new technique that produces electrolytic silver ions for pool disinfection. The method is promising, but more time is needed for evaluationof actual usage
Bromine Disinfection
like chlorine, is an element in the halogen family that is in a liquid state at room temperature and has suitable properties for pool water disinfection.
The components of a pool
pool basin; pool deck; safety fence; safety equipment; deck markers; buoyed line; main drain; water skimmers or gutters; piping; valves; hair and lint strainer; a recalculation pump; pressure and vacuum gauges; flow meters; filters and disinfectant and chemical feed pumps; and water inlets.
Chlorine Generators
recent technology has produced electrolytic cell type chlorinators which use sodium chloride, either in the pool or in a seperate cell, to produce chlorine, which is then injected into the recirculation line
Dissloving Chamber
sticks of solid bromine compound are placed in a cylinder through which water flows at a controlled rate.The bromine compund dissolves and provides a bromine solution that is injected into the pool.
Some recent developments that have cause concern include:
the impact on air qualityfrom chloroform and chloramines used in pools; disease hazards from endoplasm particles; cryptosporidium and pseudomonas; and safety issues, such as high-velocity slide systems, poorly tested or unproved water treatment chemicals, and one-upmanship in facility design.
10
An increase or decrease of 1 on the pH scale represents a ____-fold increase or decrease in acidity or basicity. For example, a solution with a pH of 5 is 10 times more acidic than a solution with a pH of 6.
Rapid Rate High Rate
Sand filters are typically of two types, _______ _______ and _______ _______.
Temperature Factor Calcium Hardness Factor Alkalinity Factor
Saturation Index= pH + TF + CF + AF - 12.1 Where: TF= _______ _______; CF= _______ ______ _______; AF= ______ _______
hot sunny NOT
Some pool operators deliberately add ammonia to retain the residual chlorine on ______, ______ days. However, this is ______ an acceptable practice.
water hardness
Spa _______ _______ levels should be kept between 100 and 400 ppm
Spa or Hot Tub
Water in the systems often reaches an ideal temperature (Max 104 degrees) for the rapid proliferation of bacteria and encourages the growth of disinfectant-resistant organisms.
Bathing Load
_______ _______ dictates the rate of circulation (turnover) period required.