Ventilation and air cleaning in the context of infection risk:results from two large Dutch research projects

Ventilation and air cleaning are two important means of supporting indoor air quality in the context of the risk of exposure to pathogens. This paper presents two results, from Dutch research projects, related to expressing ventilation effectiveness and portable air cleaner performance. A new test facility was used in this research. The results show that in-room performance indicators like the source-specified surface-averaged concentration add to the understanding of ventilation performance in the context of contaminant exposure. For portable air cleaners, the standardized clean air delivery rate (CADR) assessment procedure is relatively robust, but local variations in a large room are better captured by the so-called practical CADR assessment procedure.