UVC, or germicidal UV, is a portion
of the ultraviolet spectrum around the 200-280 nanometer wavelengths.
A UVC source can cause a photochemical reaction in the DNA and RNA of bacteria and viruses, eliminating the ability for reproduction.
What is UVC?
Ultraviolet (UV) is the band of wavelengths on the electromagnetic spectrum that is just below visible light. Ultraviolet light is commonly divided up into smaller bands. UVA and UVB are bands of longer wavelength UV light and are commonly associated with the type of irradiation that the sun provides. UVC is a shorter wavelength band that is also emitted by the sun; however, the Earth’s atmosphere blocks it out. This is essential to life on earth because UVC can be detrimental to living cells.
Disinfection with UVC
UVC is harmful to living cells because of the interaction it has with the DNA (or the RNA in the case of SARS-CoV-2) in those cells. The DNA of a virus or bacteria provides that pathogen instructions on how to reproduce. When the DNA absorbs UVC energy, its base members are broken or rearranged. With the blueprint for reproduction scrambled, the pathogen is no longer able to replicate itself and infect a host. It is essentially “inactivated.” This inactivation occurs for all infectious microorganisms: viruses, funguses/spores, bacteria.
Where is it Used?
Because UVC is so effective at inactivating or “killing” pathogens, it has been used for decades in hospital wards to disinfect surfaces as well as air. Numerous studies have shown UVC’s effectiveness in reducing hospital acquired infections (HAIs). UVC is an effective treatment for disinfecting drinking water, or improving air quality in HVAC systems. You can also find UVC being used in the food packaging industry to address food-borne pathogens. In light of the COVID pandemic, UVC is being used more prevalently to reduce viral loading in the air and on surfaces.