The family of the corona viruses has been known for a longer period of time – but not in this special form. Besides those there are a variety of viruses, which can do harm to human beings. The most known are the influence viruses. But what makes those viruses so dangerous? This is the ability of the spreading. For a long time it was supposed that viruses can only spread via contact. In the meanwhile it is proven, that viruses spread via our most important food -  the air. The majority of the diseases of the upper respiratory tract is caused by viruses. Fine aerosol droplets directly deposit on the mucous membrane of the nose, mouth and throat and cause infections. The disease infections is caused by the build up of aerosol from sneezing, coughing and via direct contact. Besides the classical respiratory viruses also the pathogenic germs of enteral infections first get into the respiratory tract before the gastrointestinal tract is infected. Regardless of human rhinoviruses (coryza), influence (flu), echoviruses (influenza infect, diarrhea) or measles or also mumps viruses. Via the transmission way of the air, all of those human pathogen viruses get access within the respiratory tract of human beings.

One solution is the disinfection based on ultraviolet radiation (UV-C). The UV-C radiation was discovered in 1801 by the German physicist Johann Wilhelm on the basis of knowledge about the blackening of silver salts under the influence of sunlight. In 1877, the British scientists Downs and Blunt made the discovery that under the influence of sunlight the number of microorganisms is greatly reduced. Subsequent studies have confirmed that the invisible spectrum of solar radiation with a wavelength of less than 320 nm has a germicidal effect. For the lethal dosage of viruses or other harmful microorganism e.g. bacteria, molds and fungal the exact radiation 254 nm. This radiation has the strongest effect on germs on their disposition in the cell nucleus. Viral agents as e.g. the influence virus can be destroyed with relatively low radiation intensity of 6,8 Ws/cm2. An important advantage of the physical UV-disinfection is the prevention of resistance. The UV disinfection is also functioning even when germs already have build up a resistance against common disinfection procedures  like
alcohol or antibiotics. The UV radiation is functioning with all microorganism – regardless of E-Coli bacteria, SARS, corona, legionella or fungal. A sufficient lethal UV-dosage together with long term application know-how and the required equipment technology are needed of the defined success. Especially within the last years, the number of scientific studies had been increased significantly.

Besides the UV-C Disinfection with 254 nm the UV-C/Ozone disinfection with 185 nm can be used as a germ-killing method. Ozone has the ability to react with organic osmogene (responsible for odors) and to oxidize them. At the same time, microorganisms, bacteria and spores of fungi located in the air and on surfaces are contaminations which are deactivated as under the influence of sunlight. The result of oxidation is again oxygen, for clean and fresh air. Since ozone is a gas, it penetrates also the most inaccessible places, providing complete disinfection of air and surfaces.

UV/Ozone air purifiers operate according to the principle of photolytic oxidation. This technology is based on the generation of ozone obtained from oxygen in the air under the influence of controlled UV radiation – an environmentally friendly, natural process, during which dangerous by-products such as nitrogen oxides are not formed. After microorganisms and odor molecules decay under the influence of UV-C light and react with ozone which combines with the molecules, it decays and oxygen remains as the decay product. The result of the air treatment plant operation is fresh air, reminiscent of air after a thunderstorm, which confirms the natural nature of the cleaning.

When ozone is produced under high voltage (for example, using ozone generators), if pure oxygen is not used, nitrogen oxides (NOx) are formed.