Hydrogen Peroxide Methods for Decontaminating N95 Filtering Facepiece Respirators

Introduction: During a pandemic, when the supply of N95 filtering facepiece respirators (FFRs) is limited, FFRs may be decontaminated by methods that inactivate pathogens as long as they do not damage FFR function. Hydrogen peroxide (H₂O₂) is widely used for decontamination in medical settings. Objective: To review the literature on the use of H₂O₂ to decontaminate N95 FFRs and identify methods that inactivate virus and preserve FFR filtration efficiency and fit. Methods: The literature was searched for studies evaluating H₂O₂ decontamination methods on inactivating SARS-CoV-2 and other viruses and microorganisms inoculated on N95 FFRs and the effects on respirator filtration efficiency and fit. Current U.S. Federal guidelines are also presented. Results: Findings from relevant laboratory studies (N = 24) are summarized in tables. Commercially available H₂O₂ decontamination systems differ on how H₂O₂ is delivered, the temperature, the duration of treatment, and other factors that can impact N95 FFR filtration efficiency and fit. Some methods inactivate SARS-CoV-2 virus-contaminated N95 FFRs with >3 log attenuation, whereas other methods are yet to be evaluated. Discussion and Conclusion: Most of the H₂O₂ methods reviewed effectively decontaminate N95 FFRs without damaging FFR function. However, some methods adversely impact N95 fit or filtration efficiency, which could go undetected by the end user and compromise their protection from pathogen inhalation. When making decisions about H₂O₂ decontamination of respirators, it is important to understand differences in methods, effects on different FFR models, and potential hazards to workers who manage the decontamination process.