Environmental sanitation through the use of UV-C rays
In order to ensure the safety of people indoors, the need has now arisen to go beyond the albeit important simple cleansing and cleaning operations and to guarantee real sanitisation for those sharing spaces and equipment.
In this area, germicidal UV-C rays, discovered at the end of the nineteenth century [the eighteen hundreds], are one of the elements that have been proven over the years to be among the most effective in inactivating viruses and bacteria. These are the rays with the shortest wavelength in the UV spectrum, normally blocked by our atmosphere but reproducible by special mercury vapour lamps.
UV-C radiation has the ability to modify the DNA or RNA of microorganisms preventing them from reproducing and therefore being harmful. For this reason, it is used in various applications, such as disinfection of food, water and air. In vitro studies have clearly shown that UV-C light is able to inactivate 99.99% of the influenza virus in aerosols. The virucidal and bactericidal action of UV-C has been demonstrated in studies on MHV-A59 virus, a mouse analogue of MERS-CoV and SARS-CoV-1. Application to droplets containing MERS-CoV resulted in undetectable levels of the MERS-CoV virus after only 5 minutes of exposure to the UV-C emitter (a percentage reduction of more than 99.99%) and were also effective in sterilizing blood samples. In particular, more than 95% of the aerosolized H1N1 influenza virus has been demonstrated to be inactivated by a nebulizer capable of producing aerosol droplets similar in size to those generated by human coughing and breathing. (ISS Covid-19 report n° 25, 2020).