Figure 2.

 Inactivation of Escherichia coli (a) and Staphylococcus aureus (b) in the wet state by low‐concentration ClO₂ gas. Drying was not performed for bacteria in the wet state (see Materials and methods). This represents samples with no organic load. The asterisks indicate reductions of >2 log₁₀ (*) and >5 log₁₀ (**) as compared with control values (in ordinary air). The double asterisks represent below the detection limit (<12 CFU per dish) of the assay. Data represent mean ± SD (n = 4). (•) air (control); (○) ClO₂ gas (mean 0·05 ppmv).