Development and validation of technologies suitable for the decontamination and re-use of contaminated N95 filtering facepiece respirators in response to the COVID-19 pandemic

Abstract

Background COVID-19 has brought significant challenges to society globally, particularly in the area of healthcare provision. A pressing need exists in protecting those tasked with delivering healthcare solutions during the COVID-19 crisis by providing solutions for preserving adequate supplies of effective personal protective equipment (PPE). Aim To evaluate and validate available methods for the decontamination of N95 filtering facepiece respirators (FFRs) while maintaining functionality during re-use. Methods Multiple low temperature steam and vaporized hydrogen peroxide (VHP) technologies were assessed for inactivation of Mycobacterium sp. and Feline calicivirus (employed as representatives of the contamination challenge). Findings Virus (≥ 3log 10 ) and Mycobacterium sp. (≥ 6log 10 ) inactivation on varying types of N95 FFRs using an array of heat (65-71 o C), humidity (>50% RH) and VHP without affecting the performance of the PPE. Conclusion Methods have been validated and were authorized by the United States Food and Drug Administration (US FDA) under a temporary Emergency Use Authorization (EUA). Based on findings, opportunities exist for development and deployment of decontamination methods made from simple, general-purpose materials and equipment should a future need arise.

Spreading a Durable Protective Layer of Quaternary Ammonium Agents on an N95 Respirator for Predecontamination of Airborne Mycobacterium tuberculosis and Viruses Using Mycobacterium smegmatis and Bacteriophage MS2 as Models

“…The use of engineering controls such as ultraviolet germicidal irradiation (UVGI) to prevent the spread of infectious droplet nuclei should reduce the concentration of airborne microbes [6]. Nevertheless, during the pandemic, filtering facepiece respirators (FFRs) have been widely used to protect individuals from respiratory infections [7,8]. Among FFRs, the N95 respirator exhibits a filtration efficiency of at least 95% or higher when it is used to capture bacteria or viruses [9].…”