WATER PURIFICATION mETHODS
INTRODUCTION Purification, also known as disinfection, is the process of removing organic and inorganic chemicals and particles from water to improve color, taste, and smell. This process does not guarantee microbiologic safety because it may not remove enough microorganisms, leaving a small risk of infection even after purification. The best solution is to use a variety of methods to ensure safety (Backer, 2002). Before purifying, water should be filtered with a water filter, paper towels, a coffee filter, or a clean cloth to remove particles (Miner, 2013).
TYPES There are many ways to purify water: boiling, chemical treatments, UV light, distillation, etc.
BOILING WATER Rapidly boiling water for 1 minute is the safest and most effective way to kill all bacteria, disease-causing organisms, and giardia cysts by forcing organic chemicals out of the water (Curtis, 1998) but will not remove other contaminants such as heavy metals, salts, and most other chemicals (Miner, 2013). At altitudes above 6,562 feet (>2000 m) the Centers for Disease Control and Prevention (CDC) recommends boiling
Advantages: Boiling is an easy way to disinfect water because electric or gas ranges, camp stoves, wood fires, or microwave ovens all can be used. Disadvantages: Boiled water can have a stale taste, it requires high temperatures, it is time consuming, fuel sources may be unavailable, a limited amount can be boiled at one time, and it doesn’t prevent recontamination during storage (UNL Water, 2013). Adding a pinch of salt to each quart, pouring water back and forth between containers to incorporate oxygen (this does present the risk of recontamination from handling), and adding flavors to the water, such as lemonade mix, will help to improve the taste (Curtis, 1998).
CHEmICAL TREATmENTS
water for 3 minutes; at higher altitudes, water boils at a lower
The most common chemical treatments consist of the halogens
temperature (Backer, 2010). After boiling, let the water sit and
chlorine and iodine. There are a variety of different versions of
cool to room temperature in its container (Clark, 2013). Do
these chemical treatments, so it is important to carefully follow
not add ice to quicken the cooling process (CDC, 2013).
the directions for each treatment. It is also important to pay attention to expiration dates and when the bottle/package was opened because the treatments become ineffective with time (Backer, 2010).
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EMERGENCY WATER
