UV-C light is part of ultraviolet radiation with a wavelength of 200 to 280 nm (specified in PN-90 / E-01005). It is a common method of conducting specialised disinfection mainly in medical facilities and food processing plants. Used to disinfect surfaces, air and water. The disinfecting effect consists in the penetration of high-energy particles of UV-C rays through the cell membrane of the pathogen. Then, as a result of the absorption of particles by DNA / RNA cell proteins, their structure is permanently damaged. This process is irreversible, which means that from that moment the pathogen cannot survive or reproduce.
The process described above is responsible for the elimination and neutralisation of 99.99% of microorganisms, including pathogenic pathogens, with appropriate exposure to UV-C radiation.
The amount of UV-C radiation on a given surface ensuring effective disinfection is strictly defined. The effective radiation dose expressed in millijoules (mJ) per square centimetre (cm2) of the surface is 50 mJ / cm2.
The success of UVC surface disinfection will vary according to the type of the material to be disinfected. This relates to both the type of germ (e.g. Covid-19 and their stains) and to the texture of the surface.
One aspect that has been unclear is exactly how long Sars-CoV-2, the name of the virus that causes the disease Covid-19, can survive outside the human body. Some studies on other coronaviruses, including Sars and Mers, found they can survive on metal, glass and plastic for as long as nine days, unless they are properly disinfected. Some can even hang around for up to 28 days in low temperatures.