Test methods for estimating the efficacy of the fast‐acting disinfectant peracetic acid on surfaces of personal protective equipment

Aims The work aimed at developing and evaluating practically relevant methods for testing of disinfectants on contaminated personal protective equipment (PPE). Methods and Results Carriers were prepared from PPE fabrics and contaminated with Bacillus subtilis spores. Peracetic acid (PAA) was applied as a suitable disinfectant. In method 1, the contaminated carrier was submerged in PAA solution; in method 2, the contaminated area was covered with PAA; and in method 3, PAA, preferentially combined with a surfactant, was dispersed as a thin layer. In each method, 0·5–1% PAA reduced the viability of spores by a factor of ≥6 log10 within 3 min. The technique of the most realistic method 3 proved to be effective at low temperatures and also with a high organic load. Vaccinia virus and Adenovirus were inactivated with 0·05–0·1% PAA by up to ≥6 log10 within 1 min. The cytotoxicity of ricin was considerably reduced by 2% PAA within 15 min of exposure. Conclusions PAA/detergent mixture enabled to cover hydrophobic PPE surfaces with a thin and yet effective disinfectant layer. Significance and Impact of the Study The test methods are objective tools for estimating the biocidal efficacy of disinfectants on hydrophobic flexible surfaces.