on behalf of the British Occupational Hygiene Society doi:10.1093/annhyg/mep070 Evaluation of Five Decontamination Methods for

Concerns have been raised regarding the availability of National Institute for Occupational Safety and Health (NIOSH)-certified N95 filtering facepiece respirators (FFRs) during an in-fluenza pandemic. One possible strategy to mitigate a respirator shortage is to reuse FFRs fol-lowing a biological decontamination process to render infectious material on the FFR inactive. However, little data exist on the effects of decontamination methods on respirator integrity and performance. This study evaluated five decontamination methods [ultraviolet germicidal irra-diation (UVGI), ethylene oxide, vaporized hydrogen peroxide (VHP), microwave oven irradi-ation, and bleach] using nine models of NIOSH-certified respirators (three models each of N95 FFRs, surgical N95 respirators, and P100 FFRs) to determine which methods should be considered for future research studies. Following treatment by each decontamination method, the FFRs were evaluated for changes in physical appearance, odor, and laboratory perfor-mance (filter aerosol penetration and filter airflow resistance). Additional experiments (dry heat laboratory oven exposures, off-gassing, and FFR hydrophobicity) were subsequently con-ducted to better understand material properties and possible health risks to the respirator user following decontamination. However, this study did not assess the efficiency of the decontami