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Lesson 38 |
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Water and the traveller |
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What does this text describe? |
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Contamination of water supplies is usually due to poor sanitation close to water sources, |
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sewage disposal into the sources themselves, leakage of sewage into distribution systems or contamination with industrial or farm waste. |
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Even if a piped water supply is safe at its source, it is not always safe by the time it reaches the tap. |
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Intermittent tap-water supplies should be regarded as particularly suspect. |
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Travellers on short trips to areas with water supplies of uncertain quality |
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should avoid drinking tap-water, or untreated water from any other source. |
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It is best to keep to hot drinks, bottled or canned drinks of well-known brand names- |
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international standard of water treatment are usually followed at bottling plants. |
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Carbonated drinks are acidic, and slightly safer. |
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Make sure that all bottles are opened in your presence, and that their rims are clean and dry. |
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Boiling is always a good way of treating water. |
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Some hotels supply boiled water on request and this can be used for drinking, or for brushing teeth. |
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Portable boiling elements that can boil small quantities of water are useful when the right voltage of electricity is available. |
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Refuse politely any cold drink from an unknown source. |
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Ice is only as safe as the water from which it is made, |
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and should not be put in drinks unless it is known to be safe. |
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Drinks can be cooled by placing them on ice rather than adding ice to them. |
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Alcohol may be a medical disinfectant, |
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but should not be relied upon to sterilize water. |
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Ethanol is more effective at a concentration of 50-70 percent; |
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below 20 per cent, its bactericidal action is negligible. |
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Spirits labelled 95 proof contain only about 47 per cent alcohol. |
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Beware of methylated alcohol, |
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which is very poisonous and should never be added to drinking water. |
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If no other safe water supply can be obtained, |
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tap water that is too hot to touch can be left to cool and is generally safe to drink. |
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Those planning a trip to remote areas, or intending to live in countries where drinking water is not readily available, |
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should know about the various possible methods for making water safe. |