POTABLE WATER
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Potable water is defined as safe and clean water which is suitable for drinking and cooking by human beings.
Properties of potable water:
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It should be transparent, colorless and odorless.
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Sufficient dissolved oxygen and other essential minerals should be present in it.
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It should be free of germs, toxins and other microbes.
Purification of water:
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Water purification is the process of removing undesirable chemicals [salts], biological contaminants [microbes], suspended solids [sand, silt, clay] and gases from contaminated water.
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The goal is to produce water fit for drinking and other human consumption medical, pharmacological, chemical and industrial applications.
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Process of water purification at large scale includes the following steps: Collection, Sedimentation, Filtration, Chlorination and Supply.
Purification of water at home:
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Water supplied at home may not be completely free of impurities so some precautionary purification methods should be followed at home.
Boiling:
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It is one of the easiest and safest method water purification at home. Water is boiled at 100oC for 15- 20 minutes and cooled down to room temperature. Boiling kills the microbes present in water making it fit for drinking.
Addition of chemical tablets:
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Chemicals like chlorine tablets and potassium permanganate are used to kill the harmful agents and excess salt removal.
Use of filters: physical and electrical:
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Traditionally water is filtered by using the cloth. However nowadays electric filters, RO systems, Water purifiers are available in market. Commonly these modern units contain micro-porous filters, carbon and a source of UV radiation. Filters strain the impurities, carbon absorbs organic impurities and UV radiation kills the microbes.
