What is Ultra Violet or UV Sterilization?


Many consumers have heard the term UV or Ultra Violet sterilization, but are not exactly sure what the process actually entails or how it works.  UV sterilization is in fact one of the most   efficient and dependable forms of disinfecting in producing clean and safe water.What is Ultra Violet or UV Sterilization?

How UV Sterilization Works

What is UV?  It’s actually light.  Ultraviolet is a light spectrum just below the visible range for the human eye. UV light has four spectral areas; Vacuum UV, UV-A, UV-B and UV-C. The design of UV is meant to sterilize and render harmful or unwanted microorganisms inert within the liquid. According to the Water Quality Association UV systems expose the water to the UV light using just the right wavelength to kill microbes.  The UV light system is a method to kill bacteria, fungi, viruses that might be in the water.  The light source must be kept clean.  This creates a very effective and efficient way to control the levels of bacteria and pathogens in a drinking water supply.

In order to make UV sterilization effective, the microorganisms need to first be identified. Every microorganism requires a certain exposure rate (and they may be different) to UV-C radiation to complete the process of disinfection. Once the target organism is identified, it can be directly irradiated long enough to penetrate the cell wall. This may only take a matter of seconds, but once the UV-C has broken through the cell wall, its DNA is critically disrupted. This will not only impair its reproduction ability, but may also totally destroy the offending organism.

The Benefits of Ultra Violet

UV sterilization or germicidal disinfection is unique in that it cannot be matched by chlorine or ozone methods in both safety and simplicity. Chlorine disinfectant leaves residue in the water, which can be an irritant for the eye and skin tissues. Incorrectly controlled or measured ozone is may cause tissue damage.  UV sterilization on the other hand occurs within the exposure chamber, leaving no residual effects downstream. This means that the process will not compromise the water table AT ALL and has no adverse effects on animals and wildlife. UV sterilization has been proven to successfully treat a wide range of waterborne viruses, pathogens, bacteria, protozoa and algae, which are common in re-circulating aquatic systems.

UV’s Limitations

As great as it is, UV is not perfect.  The UV sterilization process must occur within an exposure housing. The exposure time is critical for successful results. The success rate can be affected by the condition of the water, which may reduce the amount of UV penetration.  Since the UV wavelength is absorbed by the microorganism and organic waterborne particles, the equipment must be ideally positioned after filtration which will allow exposure to solids free water.

UV sterilization may seem to be more technically complex than many forms of chemical sterilization, however, once the target microorganisms have been identified and the dose is calculated, it can produce far superior and cleaner less toxic results in making it better for the environment and the consumer.

About The Author, Terry Reeh, EcoWater Systems of Nebraska:

With more than 25 years experience in the residential and commercial water treatment space, Terry is a WQA (Water Quality Association) certified water specialist, LEVEL 3, as well as a WQA certified sales representative.  EcoWater Systems of Nebraska is one of the biggest water treatment and water delivery businesses in the state, Terry currently sits on EcoWater Systems (a Berkshire Hathaway Company) national Peers committee, as a water treatment expert advising other water professionals with less experience on best trade and technology practices.

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