Impact of Three Single-Step Decontamination Methods on Respirators and Medical Gowns

During the COVID-19 pandemic, many methods of decontamination were proposed to combat the severe shortages of disposable personal protective equipment (PPE), such as N95 respirators and gowns, for healthcare workers. Although several decontamination methods were granted emergency use authorizations for N95 respirators, no methods were granted for gowns. The main concerns for decontamination of disposable PPE are twofold. First, the method must adequately decontaminate the PPE, and second, the device must retain its performance requirements after decontamination. The current study examined autoclave sterilization and single-step gaseous ozone decontamination methods for decontaminating N95 respirators and gowns, while microwave-generated steam decontamination was also used for N95 respirators. We found that N95 respirators could undergo major deformation due to decontamination, but this deformation was not reflected in filtration efficiency, pressure drop measurements, or tensile strength measurements. These findings underscored the importance of other methods that define the protective performance of the product (e.g., fit testing) for assessing the impact of decontamination on N95 respirators. Surgical gowns maintained their protection level regardless of decontamination type, but not enough samples were tested for a proper acceptable quality level determination. For isolation gowns, autoclaving resulted in catastrophic material failure due to high heat, but the gentler decontamination method using gaseous ozone resulted in a lower failure rate for the material.