Friday, May 2, 2008

Home Made Water Purifier

Ever wondered how you could make your own water purifier? It is risky business to do so because it is not possible to tell whether water is safe to drink just by looking at it.

Simple procedures such as boiling or the use of a household activated carbon filter are not sufficient for treating all the possible contaminants that may be present in water from an unknown source. Even natural spring water - considered safe for all practical purposes in the 1800s - must now be tested before determining what kind of treatment, if any, is needed. Chemical analysis, while expensive, is the only way to obtain the information necessary for deciding on method of purification.

To use a home made water purifier you will need to first determine what contaminants you will need to remove from the water, and then choose the proper method to achieve the result you seek.

If you desire a source of clean water at home over the long-term, you will get much better results from many of the products offered commercially; especially where extensive research and cutting edge technology has been developed to achieve the most effective reduction of contaminants. No home made water purifier will come close to removing the number and types of contaminants handled by most commercial water purification systems. Your safety and health can depend on getting the water right.

Water purification technologies includes, but are not limited to: ultraviolet light, filtration, water softening, reverse osmosis, ultrafiltration, deionization and powdered activated carbon treatment. All of these methods can be found in a wide range of products for the home at relatively reasonable prices.

In a pinch, you can achieve a home made water purifier. The following water purification methods are taken from the Outdoor Action Guide to Water Purification, part of The Backpacker's Field Manual by Rick Curtis.

Biologically Contaminated vs. Toxic Water

Biologically contaminated water is water that contains microorganisms such as Giardia (a common microorganism that, if not killed, leads to intestinal disorders), bacteria, or viruses that can lead to infections (see Gastrointestinal Infections, page 316). Toxic water sources, on the other hand, contain chemical contamination from pesticide runoffs, mine tailings, and so on. A home made water purifier that involves boiling, filtering, or chemically treating water can remove or kill microorganisms, but it will not remove chemical toxins.

Boiling

Boiling is the most certain way of killing all microorganisms. According to the Wilderness Medical Society, water temperatures above 160° F (70° C) kill all pathogens within 30 minutes and above 185° F (85° C) within a few minutes. So in the time it takes for the water to reach the boiling point (212° F or 100° C) from 160° F (70° C), all pathogens will be killed, even at high altitude. To be extra safe, let the water boil rapidly for one minute, especially at higher altitudes since water boils at a lower temperature (see page 68.)

Chemical Purification

There are two types of chemical treatment: those using iodine and those using chlorine. There are a variety of products on the market, so follow the directions on the bottle. Be advised that many of the tablets have an expiration date and become ineffective after that point. Also, once the bottle has been opened, the tablets must be used within a certain period. When in doubt, buy a new bottle. Remember that chemical purification methods may only be partially effective, depending on the water temperature.

Iodine has been shown to be more effect than chlorine-based treatments in inactivating Giardia cysts. Be aware that some people are allergic to iodine and cannot use it as a form of water purification.

Chlorine Treatment

Chlorine can be used for persons with iodine allergies or restrictions. Remember that water temperature, sediment level, and contact time are all elements in killing microorganisms in the water. Chlorine is also a toxic substance and if not used properly or used over time can be very harmful. Home made water purification over the long-term is not a healthy or effective way to assure clean drinking water.

Filtration

There are a number of devices on the market that filter out microorganisms. A water filter pumps water through a microscopic filter that is rated for a certain-size organism. The standard size rating is the micron (the period at the end of this sentence is about 600 microns). Depending on the micron rating of the filter, smaller organisms (like viruses) can pass through.

Be cautious when selecting a filter. You should know what potential organisms you need to treat for. You don't want to go to an area where a virus like hepatitis A is present in the water (a problem in some developing countries) with a filter that will handle only a larger organism like Giardia.

If what I have told you makes it seem like a home made water purifier is more risky and more trouble than it's worth, then maybe it's time to consider a simple, easy to use, affordable commercial home water purifier. I personally recommend the Aquasana brand for it's portability (if you move, just unplug it and move it to your next house), its affordable cost and its effectiveness in removing all sorts of contaminants.