UV Sterilization for water, how it works and what it does
Ultraviolet or UV sterilization is an extremely dependable and efficient form of disinfection in generation of clean, potable and safe water. Homeowners may be familiar with, or heard of the term… But what is exactly and how does UV sterilization work?
How UV Sterilization Works
Ultraviolet light is 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 goal of UV as a means of sterilization is to render unsafe or unwanted microorganisms inert. For sterilization purposes UV-C provides the most lethal spectral range. UV-C at 264 nanometers provides a peak wavelength for altering the DNA of virtually all waterborne pathogens and bacteria, preventing microorganisms from reproducing. This creates a very effective and efficient way to control their levels in any water supply.
Every microorganism requires a certain exposure rate to UV-C radiation to complete the process of disinfection. I n order to successfully achieve UV sterilization, the microorganisms need to first be identified. Once the target is identified, it can be exposed to the radiation long enough to penetrate the cell wall. This usually takes a matter of seconds only, but once the UV-C has broken through the cell wall, its DNA is disrupted. This will not only impair its reproduction ability, but may also totally destroy the organism.
The Advantage of UV Sterilization vs. other forms of disinfection
Chlorine or ozone protocols cannot match UV sterilization or germicidal disinfection in efficacy or simplicity. Chlorine leaves chemical residue in the water, which can be an irritant for the eye and skin tissues. Incorrectly controlled ozone is also capable of causing 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 and has no harmful effect on flora or fauna. UV sterilization has been proven to successfully treat waterborne bacteria, protozoa, algae, viruses and a broad range of pathogens in water systems.
What are the Limitations of UV Sterilization?
UV sterilization is more complex than many forms of chemical sterilization. Also, the UV Sterilization process occurs specifically within an exposure housing. The exposure time is therefore critical. The success rate can be affected by the condition of the water, which may reduce the amount of UV penetration. Additionally, since the UV wavelength is absorbed by the microorganism and organic waterborne particles, the equipment is ideally positioned after filtration.
All this said, once the target microorganisms have been identified and the dose is calculated, as a means of sterilization, UV can produce far superior and cleaner results, making it better for environment and consumer alike.
About The Author, Terry Reeh, Partner 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. In addition to running the day-to-day operations of EcoWater Systems of Nebraska, one of the biggest water treatment and water delivery enterprises 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.