Neutralization method evaluation is an important first step in a disinfectant validation study program. It is also crucial in assessment of the efficiency of microbial recovery media in the presence of a residual biocidal agent. In the present study, four commercially available peroxygen/silver-based disinfectant formulae – intended to be used in a pharmaceutical facility sanitization program – were tested at two dilutions against three Gram-positive cocci and one yeast;