Figure 2: Position of the “Mini Dry Fog” device (DF, orange; arrow shows spray direction of nozzle), data loggers (DL 1-3, green) and germ carriers (GC, blue) in the BSC; Biological indicator localisations are: GC1: lower exhaust plenum; GC2: in closed Petri dish in workspace; GC3: workspace, left side; GC4: workspace, right side; GC5: upstream side recirculation filter; GC6: exhaust plenum, in airflow; GC7: upstream of exhaust filter; GC8: exhaust plenum, “dead angle”; GC9: downstream of exhaust filter