A crystal-clear stream or lake usually contains microorganisms that can make you sick. Water contaminants - protozoa, bacteria and viruses - can cause serious illness or even death. Fortunately, portable drinking water systems can help make water safe to drink. They have become essential outdoor equipment worldwide.
Most of us would like to think that our lakes, streams and rivers are as clean as they are sparkling. Unfortunately, the U.S. Environmental Protection Agency (EPA) reports that 90 percent of the world's fresh water is contaminated. While Giardia is often considered the primary water-safety concern, wilderness studies suggest that many backcountry illnesses are actually caused by bacteria or viruses. Since you never know what's in the water, it makes sense to always use a quality drinking-water system.
The summary of the chart listed below is Purifiers provide the most protection. Microfilters offer the next most protection, and filters offer the least protection.
Drinking Water Safety Guide
Microbiological Micron Rating
The Highest Level of Safety Available. Purifiers eliminate ALL microorganisms from water, including viruses
Removes microorganisms, including protozoa and bacteria. For protection against viruses, an EPA registered disinfectant may be added to the water after it is filtered.
.3 to 1.0
Removes Giardia, other large protozoa, and some bacteria.