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Do I need a Water Filter? |
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A water filter is a
device which removes impurities from water by means of a fine physical
barrier, chemical processes and/or biological process. Filters are used
to cleanse water for irrigation, drinking water, aquariums, and swimming
pools.
Water filters are primarily
used to soften water and remove chemicals such as chlorine. Some
scientists believe that the contaminants found in drinking unfiltered
drinking water can be harmful to your health, even increasing the risk
of developing cancer. The most common problem with unfiltered water,
however, is a bad taste or smell.
Water filters are also used
by recreational hikers, by aid organizations during humanitarian
emergencies, and by the military. These filters are usually small,
portable and light (1-2 pounds or less) and usually filter water by
working a mechanical hand pump, although some use a siphon drip system
to force water through. Dirty water is pumped via a screen-filtered
flexible silicon tube through a specialized filter, ending up in a water
bottle (or other container, such as a Camel Back). These types of
filters work to remove bacteria, protozoa and cysts, all of which can
cause disease. Popular and reliable makers of these small, portable
water filters include General Ecology, Innova Pure Water,
Katadyn,Mountain Safety Research, and Pure Water 2GO. Filters include
fine meshes, which must be replaced, and ceramic filters which must have
their outside abraded off when it becomes clogged with impurities.
These water filters should
not be confused with devices or tablets that are water purifiers. Water
purifiers satisfy higher EPA standards, and also remove viruses, such as
hepatitis A and rotavirus, among others.
In a domestic emergency,
where water needs will last beyond those of stored, bottled water, a
device that is specifically certified as a water purifier, and not a
water filter, is preferred.
The physics of filters is
based on sieving, adsorption, ion exchanges and other processes. Unlike
a sieve or screen, a filter can remove particles much smaller than the
holes through which the water passes. ©copyright Learn-about-it.com 2007 Water Filters |
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