Decontamination of Personal Protective Equipment

Exploratory field analyses of the inactivation capacity of disinfectants on contaminated personal protective equipment (PPE) are required to select a suitable surrogate for biohazardous agents like spores of Bacillus anthracis. The objectives of our study were (1) the determination of an appropriate surrogate for the inactivation of spores of B. anthracis with peracetic acid (PAA), and (2) application of optimized inactivation conditions for an effective decontamination of PPE with PAA under field conditions. For inactivation studies, B. anthracis spores from different strains and B. thuringiensis spores were fixed by air drying on carriers prepared from PPE fabric. Time and concentration studies with PAA-based disinfectants revealed that the spores of the B. thuringiensis strain DSM 350 showed an inactivation profile comparable to that of the spores of the B. anthracis strain with the highest stability, implying that B. thuringiensis can serve as an appropriate surrogate. Rapid (3 to 5 minutes) and effective surface decontamination was achieved with 2% PAA/0.2% surfactant. In field studies, PPE contaminated with spores of B. thuringiensis was treated with the disinfectant. Optimizing the decontamination technique revealed that spraying in combination with brushing was effective within 5 minutes of exposure.