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14 Cards in this Set
- Front
- Back
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What is the purpose of a ground fault circuit breaker in a pool?
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GROUND-FAULT CIRCUIT-INTERRUPTER: A GFCI device protects a circuit from branching off by de-energizing the path of electricity very quickly when it senses current loss. An important safety device around water (the pool?).
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How do you prevent the pH in a swimming pool from flucuating.
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Total alkalinity is a measure of the ability of a solution to neutralize hydrogen ions.
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What is TA?
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Total alkalinity is the result of alkaline materials including carbonates, bicarbonates and hydroxides - mostly bicarbonates. This acid neutralizing (buffering) capacity of water is desirable because it helps prevent wide variations in pH whenever small amounts of acid or alkali are added to the pool. Total alkalinity is a measure of water's resistance to change in pH.
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What is the recommended pH and free available chlorine levels for pools?
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7.2 - 7.8
>0.5 |
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What is the difference b/w FAC, TC and CC?
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Free Chlorine Residual is the amount of chlorine in the pool which has not reacted with substances other than water. It is the chlorine which is available to disinfect pool water and oxidize organic substances. Free chlorine residual should be maintained >0.5
Combined Chlorine is chlorine in the pool which has reacted with substance other than water and is no longer available in its free state. Total Chlorine residual is the concentration of free chlorine plus combined chlorine. To determine combined chlorine residual test for free chlorine and total chlorine. Total chlorine = chlorine + combined chlorine |
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Describe the recirculation system of a swimming pool from pool drain to inlet.
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Water is removed from the poolthrough two main drainage systems.
a. Some water is removed through the main drain and some water is taken from the surface of the pool through the overflow system consisting of skimmers. After removal, the water flows through a pipe to a strainer or screen where hair and lint is removed. Having been strained of debris, the water then flows to the filter plant for the removal of fine-particles such as dust, body oils, algae, slime, bacteria, coagulated material, etc. This filtration aids the chemical disinfection and oxidation processes which beneficially take place after the water is returned to the pool. Pool filtration is achieved most commonly by particle entrapment in either (1) a bed of sand or (2) a thin cake of diatomaceous earth. As the pool water flows beyond the filters it is chemically treated. Chlorine disinfecting agent is added, pH adjustment chemicals are introduced, and the treated water is returned to the pool to destroy bacteria and oxidize other undesirable solids. Water is re-entered into the pool through an inlet. |
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What are the grounds for closure of a pool?
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Can't see black disc.
presence of algae no disinfection fouling no lifeguard where required. Outlet covers broken or missing. Pump broken. |
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What is the problem with algae in pools?
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Algae does not cause disease. It is a plant that turns sunlight and carbon dioxide into food and provides nutrients for bacteria which can then multiply rapidly (and may cause illness). When there is algae present in the pool water, the chlorine is used up rapidly trying to combat its growth. This process has a tendency to raise the pH, thus decreasing the efficiency of the remaining free chlorine.
Unchecked algae growth can turn the swimming pool cloudy or makes the pool water green and results in foul odours and tastes. Black algae, which is more difficult to control than green or blue-green algae, can also stain the swimming pool's walls and floor. |
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How is algae controlled?
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Usually shock treatment with chlorine or an algaecide is recommended. Proper filtration
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What is the effect of pH on chlorine?
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Chlorine reacts with water to form Hypochlorous acid (HOC1) and is the form in which chlorine serves best as a disinfectant. Hypochlorous acid is a weak acid and easily dissociates to an ionized hypochlorite.
The balance between hypochlorous acid and the hypochlorite ion is affected by pH. The higher the pH, the less hypochlorous acid present and the less effective free chlorine becomes. At a pH of 7.2 about 66% of free chlorine is hypochlorous acid. At a pH of 7.8 only about 33% of free chlorine is hypochlorous acid. Thus pH control is essential for maintaining the effectiveness of chlorine as a disinfectant. |
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What is meant by a balanced pool?
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Balanced water is the result when all of your chemical parameters are within the tolerance limits. The most important parameters of water balance are pH, Total Alkalinity, Calcium Hardness and Temperature.
If your pool water is not balanced properly, it can lead to skin and eye irritation as well as harm the equipment and surface of the pool. |
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What causes skin rashes in pools and spas?
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pseudomonas
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What is the process for closing a pool?
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Inform the operator that the pool will be closed.
Get everybody out of the pool. Lock all the gates. Post closed at the entrance. Give the operator a verbal section 13. Issue a written section 13 and list requirements to re-open the pool. Conduct inspection to see if fixed. If fixed open pool. |
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What are the requirements for depth markings in a pool?
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Every owner and every operator of a modified pool shall ensure that the pool is provided with continuous black markings on the bottom 150 millimetres wide where the water depth is 0.60 metre and 300 millimetres wide where the water depth is 1.20 metres
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