Objective: Surgical masks and N95 filtering facepiece respirators (FFRs) prevent the spread of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection and protect medical personnel. Increased demands for surgical masks and N95 FFRs during the Coronavirus disease 2019 (COVID-19) pandemic has resulted in the shortage crisis. However, there is no standard protocol for safe reuse of the N95 FFRs. This systematic review aims to evaluate the effectiveness of existing decontamination methods of surgical masks and N95 FFRs and provide evidence-based recommendations for selecting an appropriate decontamination method.
Methods: Systematic searches of Ovid MEDLINE and Ovid EMBASE electronic databases were performed. The date of the last search was 11 April 2020. Any trials studying surgical masks and/or N95 FFRs decontamination were included. Outcomes were disinfections of virus and bacteria, restorations of the filtration efficiency and the physical structure of the masks.
Results: Fifteen studies and fourteen decontamination methods were identified. Low level of evidence supported four decontamination methods, which were ultraviolet germicidal irradiation (9 studies), moist heat (5 studies), microwave generated steam (4 studies), and hydrogen peroxide vapor (4 studies). Therefore, recommendations as an 'option' were given to these four methods while 'recommendation against' was given to the other ten methods.
Conclusions: Low level of evidence supported the use of ultraviolet germicidal irradiation, moist heat, microwave generated steam, and hydrogen peroxide vapor for decontamination and reuse of N95 FFRs. These decontamination methods were effective for virus and bacterial disinfection, and restoration of the filtration efficiency and the physical structure of the FFRs.
Keywords: COVID-19; SARS-CoV-2; decontamination; disinfection; hydrogen peroxide; microwave; pandemic; severe acute respiratory syndrome coronavirus; surgical masks; ultraviolet.