Release of undesired by-products during the operation of virus inactivating air cleaning devices

Mobile air cleaner are seen as an effective tool for reducing airborne viruses in indoor air. The basis of the investigations was the determination of the reduction in virulence by means of inactivating technologies on basis of plasma- and UVC-technologies. The particle release of different particle fractions relevant to aerosols and the reduction of the virulence have been measured by injection of the non-hazardous surrogate viruses Phi6-bacteriophague with similar structure and environmental behaviour to SARS-CoV-2-virus into a climate-controlled test chamber. However, there are legitimate concerns regarding the release of harmful byproducts, e.g. ozone or volatile organic compounds (VOC). In addition to the virulence tests the devices were investigated to the formation of such substances. The released substances were finally compared with limit values of national and international standards.