How Effective is Ultraviolet (UV) Light at Killing Microorganisms?

Ultraviolet or UV irradiation is a method of sterilization that uses light at specific wavelengths to kill microorganisms that could affect our health. This method is not a new one, the 1903 Nobel Prize for Medicine recipient was Niels Finsen, he used UV light to treat tuberculosis. In fact, in the modern world UV light is used to purify water and air in a wide selection of products. Let’s take a look at what UV light is good for and examine how effective it can be as a form of purification. ultraviolet-room-1256214

How Does UV Light Purification Work? 

When UV light is used in very specific, short wavelength the radiation is very harmful to microorganisms. It works by destroying the nucleic acids in this bacterium and as a result, their DNA is disrupted by the UV light. This effectively stops the bacteria by removing their capability of reproducing and then it kills them. 

How Well Does UV Light Work in Water? 

Usually, UV light works very well at removing microorganisms in water, but turbidity or cloudiness can make it less effective. The UV radiation has difficulty penetrating water that has a lot of material present. For this reason, most experts agree that some kind of sediment filter needs to be placed in front of the UV system to remove material that can inhibit the transfer of UV light through the water. Usually, this is a step down filtration system that uses a five and then a one micron sediment filter to get the water ready for the UV disinfection chamber. 

The Advantages of Using UV Light for Purification: 

Typically, UV light is used as a final step to disinfect and sterilized water. One of the main advantages to using UV light is that it’s a non chemical method for purifying water. This makes it a good option for people that don’t like the tasted of chlorine or dislike the idea of added chemicals for disinfection purposes. The use of UV light has a number of other significant advantages, such as no significant contact time required, it cannot overdose, adds no odor to the water, it’s not hazardous, it uses no chemicals, there are no disinfection byproducts, it’s cost effective, and it is totally sustainable. 

Where Can UV Light be Used? 

We can use UV light to disinfect water in a wide variety of different applications outside the home, such as hotels, restaurants, hospitals, schools, breweries, wineries, water bottling plants, campgrounds, farms and even municipal water systems. Hopefully, in the future, we will see UV light being used more extensively to make our water safer. 

If you’re concerned about harmful bacteria in your water supply, contact a local water treatment professional. There are UV systems available that can purify your water making it safe for drinking and other activities. Always be sure that your chosen water treatment professional is fully WQA certified and you can be sure that they meet and even exceed water industry standards.

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. 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. EcoWater Systems of Nebraska is one of the biggest water treatment and water delivery businesses in the state.

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