* The surface area inoculated was equivalent to the surface area sampled when using the Rodac plate. All experiments were performed in triplicate. The average inoculum per surface area inoculated (i.e per site) was Log10 2.524 ± 0.009 cfu/site. A range of surface inoculation levels were evaluated, but higher inoculum (e.g. ≥ 103 cfu/site) of C. difficile spores produced growth that was too numerous to count when sampled using Rodac plates.