How Safe Is UV Water Purification?

Water is perhaps the most important natural resource on our planet, and yet it is one that is frequently polluted. Many different treatments that make water clean and safe for human consumption are used to remedy this situation, both in municipal water treatment plants as well as in homes, offices and other facilities. Ultraviolet light is one such method, producing safe drinking water without having a negative impact on the environment.

• Water is one of the world's greatest resources

History

• Ultraviolet Radiation (UV) light treatment is a method used to purify drinking water. Used in the United States since 1916, it is a cheap and effective treatment for otherwise clean water contaminated by bacteria and viruses.

Function

• UV treatments, according to the CDC, are used for disinfecting drinking water. Certain wavelengths of UV light are harmful to viruses and bacteria, killing them or preventing reproduction. The water is subjected to UV light for a period of time, usually under a minute, and then transferred to a clean holding tank or exits directly to the faucet to be used as drinking water.

Limitations

• However, UV water treatments are not physical or filtration treatments; depending on the water source and pollutants, other treatment systems must also be used. Very dirty water, for example, needs sedimentation or filtration treatments to remove the dirt and other particulate matter in addition to treatment to kill any pathogens.

Types of Systems

• UV treatment systems can be purchased for home or commercial use and may be used to treat the water on a demand basis (when a drinking tap is turned on, for example) or as the water enters the facility or residence (treating most or all of the water, whether it will be used for drinking or not). Smaller, more portable systems have also been developed, mostly for use in countries and contexts where safe drinking water is a luxury.

Safety

• UV disinfection is approved by the EPA, and according to the National Drinking Water Clearinghouse, the method offers no overdose danger, produces no known toxic byproducts or pollutants, and doesn't utilize hazardous material.