Engineering office Merschbrock has several years of experience in the inactivation of viruses with UVC technology.
Since January 2020, the control of human pathogenic viruses, especially the prevention of unrestrained spread of coronavirus, is of high social importance.
Disease-causing viruses are transmitted from infected persons both by droplet infection (e.g. with the expulsion of virus-containing saliva droplets or nasal secretions) or by smear infection (touching virus-contaminated surfaces with the hands and subsequent skin contact with other persons or touching one's own facial areas).
When transmitted by air, coronaviruses can "fly" one to two meters, while other viruses, such as the PRRS virus, can travel distances of several kilometers.
Viruses consist of a cell envelope, also known as a capsid, in which various proteins are embedded that enable the virus to penetrate living cells (e.g. cells of the oral and pharyngeal mucosa of humans) and multiply there without inhibition. The actual genome is embedded inside the capsid and is present either as DNA or RNA. Multiplication in the host cells usually leads to their death, which accounts for the disease symptoms of a viral infection.
Schematic representation of a coronavirus, source 
The radially arranged S proteins in the envelope membrane give the virus its name
The UVC rays penetrate the envelope membrane of the viruses and damage the RNA inside by forming pyrimidine dimers within the base pairs (for more details see the following chapterUVC disinfection technology).
In simplified terms, dimer formation can also be thought of as knot formation within the RNA strand, which prevents reliable reading of the code in the host cell ribosomes, resulting in the viruses being unable to replicate in the host cells.
Depending on the structure of the envelope membrane and the thickness of the protein structure, different UVC doses are required to inactivate the RNA.
Structure and lethal dose of some virus types
For UVC inactivation of airborne viruses in agriculture (e.g. inactivation of influenza viruses and PRRS viruses), numerous UVC disinfection systems are successfully in use (see also the following chapter).
There are also reports on the inactivation of noroviruses and hepatitis A viruses on the surface of frozen strawberries and raspberries: Inaktivierung von Murinem Norovirus und Hepatitis-A-Virus
The air disinfection systems described below are available for use in the human medical field.
For surface disinfection of consumer goods, disinfection cabinets, flow-through locks and disinfection tunnels are available.
Small sterilization cabinet for medical equipment, respirators, tablets, cell phones, etc.
Pass-through airlock for surface disinfection of larger objects
Automatic disinfection tunnel for a larger number of items to be disinfected per time unit, such as parcels and packages, cans, tools and other items that have been touched by the employees of parcel services or forwarders in this way.
 S. Modrow, D. Falke, U. Truyen und H. Schätzl, Molekulare Virologie, Spektrum Akademischer Verlag
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