VDI-EE 4300 Part 14:2021 Edition

In a pandemic, the aspect of sufficient ventilation indoors becomes a crucial issue with regard to the health of all persons staying inside. Continuous ventilation success is best ensured by a permanently installed, usually centrally controlled room ventilation system (RLT system). However, such systems are still the exception, e.g. in residential rooms or in schools and kindergartens. There, ventilation has to be ensured by opening windows regularly. This applies especially to pandemic situations. In addition to ventilation via window, virus reduction can also be supported by installing simple supply/exhaust air systems or using mobile air cleaners. Mobile air cleaners are not a substitute for ventilation via windows or RLT systems, but may be a useful addition if necessary. This VDI Expert Recommendation defines test conditions for mobile air cleaners with regard to their effectiveness tin reducing virus contamination in a real room. The effectiveness to be demonstrated, refers in each case to the entire system and not to individual components such as filters or the UV-C lamp unit. A suitable device, like all other options, lead to reduction of the virus concentration in indoor air, but this does not mean complete protection against infections. Especially in the near field (below 1,5 m) and in case of direct contact, there can still be increased risks of infection when staying indoors.