First, we need to get technical and explain the difference between a water
purifier and water filters or other water treatment devices. The U.S.
Environmental Protection Agency defines a water purifier as a device that
removes from drinking water all micro-organisms that can cause
disease.
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SYSTEMS
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CHARACTERISTICS
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IS THIS APURIFIER?
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Home Water Filters (think of filtration pitchers or
faucet-mounts)
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Most provide little germ removal. Depend on replaceable carbon
filter cartridges for improving taste and odor.
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NO
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Special Filters
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Small pores can catch big bugs like protozoa but not little
ones like bacteria and viruses. Readily clog up; replacement is
frequent.
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NO
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Ultra-violet (UV)
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Germ kill rate not 100%, especially if water is cloudy, bulb
burns out or dissolved stuff like iron blocks the UV. Expensive;
usually requires plumbing installation.
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NO
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Reverse osmosis (RO)
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Some micro-organisms can pass through small pores of plastic
membranes due to "grow-through" phenomenon. Very slow and
expensive. Requires plumbing installation.
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NO
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Distillation
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Some germs can escape from the boiler to the treated water
reservoir and reproduce in warm, treated water. Very slow and
expensive. Usually requires plumbing installation.
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SOMETIMES
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Boiling Water
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Kills all germs but does not remove other contaminants. Takes
time for water to cool to drinking temperature. Tastes like
boiled water...not a popular solution.
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YES
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Bottled Water
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Expensive. A hassle to purchase, transport and store heavy
containers. May be in short supply during an emergency.
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YES
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