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UV Disinfection System

About UV Water Purification

There are over 19 million American households and cottages that rely on private wells. Tens of thousands more rely on lakes, streams and other surface water sources. Unfortunately, not all of them have a UV water purification system protecting them from harmful microorganisms.

While a nation-wide study does not exist, smaller scale studies have commonly found that 40% of wells in any given region suffer from E. coli and/or coliform bacteria at any given time not to mention the countless other microorganisms that may be in a water supply.

The quality of well water can vary from day to day and from year to year in the short term, things like heavy rainfalls or snow melt can affect water quality. In the long term quality may be affected by distant contamination sources such as earthquakes, and other factors.

Water that has been safe for years will not necessarily be safe tomorrow.


Ultraviolet (UV) is a safe, clean, easy-to-maintain method of assuring that water is free of bacteria. UV Water Purification uses Ultraviolet light, just like sunlight, to kill micro-organisms that may be in the water. It is a proven technology that has no significant drawbacks. In some applications, its initial cost is a bit more than chlorination, but because of its low operating cost, it quickly pays for itself. It is environmentally friendly and essentially trouble-free. Most ultraviolet water treatment systems require only an annual change of lamp – as simple as changing a light bulb and a periodic change of the filter cartridge.

What is Ultraviolet (UV)

Ultraviolet or “UV” is a type of energy found in the electromagnetic spectrum, lying between x-rays and visible light. Although we cannot see UV light or rays, we are exposed to them every time we step out into the sun. In fact, UV light is responsible for causing sunburns. Ultraviolet systems use special lamps or bulbs that emit UV light of a particular wavelength.

The Ultraviolet energy attacks the genetic core of the microorganism and rearranges the DNA /RNA eliminating the microorganism’s ability to function and reproduce. If the microorganism can no longer reproduce, it cannot replicate, therefore it cannot infect other organisms with which has contact. The process is simple but effective, destroying 99.99 percent of harmful microorganisms without adding chemicals to the water.

The quality or appropriateness of both the UV light and of the ‘contact ‘, are crucial to accomplish disinfection. It is important to properly ‘size’ the UV based upon the application. It is equally important to use a good pre-filter to remove any dirt or debris that may be present in the raw water supply. This dirt and debris can interfere with the effectiveness of the UV rays – virtually giving the microorganism a shield to protect them when passing the UV rays. The keyword here is quality.  System manufacturers strongly recommend that any pre and post filters be replaced at specified periods and that the UV lamp be replaced on an annual basis or after 9,000 hours of use — whichever comes first.

Advantages of UV

There are some very important reasons why both homeowners and municipalities are choosing UV technology to treat their water.

Highly effective: For over 25 years, UV technology has been trusted as a safe, cost-effective way to purify water and eliminate harmful microorganisms. It is a proven EPA endorsed technology that is currently being used by thousands of cities, bottled water manufacturers and homeowners around the world.

Chemical free: UV provides water purification without the addition of harmful chemicals such as chlorine. It also avoids the potential of generating harmful chemical disinfection by products. Recent EPA guidelines are forcing cities across the United States to reduce or eliminate the use of chlorine for exactly this reason.

Taste & odor free: UV does not change the taste, odor or color of the water.

More effective than chlorine: Unlike chlorine, UV systems are effective against both Cryptosporidium and Giardia.

Compact and easy to maintain: UV systems are capable of treating a single faucet or an entire home in a minimal amount of space with the only maintenance being an annual lamp and filter replacements.


Water Quality

Successful disinfection depends upon exposing water to a sufficient intensity of UV light for a sufficient amount of time. Water failing to meet certain general water quality guidelines may reduce the effectiveness of a system.

For a UV system to work effectively the water must be pre-filtered to exclude any particles larger than 5 microns (nominal) in size. This pre-filtration assures that particles large enough to block the UV light do not pass through the system. If they do the particles can act as a shield between the microorganism and the UV light – protecting the microorganism and allowing it to pass into the product water unharmed and alive.

If your water is not cloudy or smelly, you do not have rust stains in your toilet, and have softened water, your water, water quality should not be an issue for your UV system.