Disinfection of Respirators with Ultraviolet Radiation

Data for interpreting virus inactivation on N95 face filtering respirators (FFRs) by ultraviolet (UV) radiation are important in developing UV strategies for N95 FFR disinfection and reuse for any situation, whether it be everyday practices, contingency planning for expected shortages, or crisis planning for known shortages. Data regarding the integrity, form, fit, and function of N95 FFR materials following UV radiation exposure are equally important. This article provides these data for N95 FFRs following UV-C irradiation (200 nm to 280 nm) in a commercial UV-C enclosure. Viral inactivation was determined by examining the inactivation of OC43, a betacoronavirus, inoculated on N95 FFRs. Different metrological approaches were used to examine irradiated N95 FFRs to determine if there were any discernible physical differences between non-irradiated N95 FFRs and those irradiated using the UV-C enclosure. Material integrity was examined using high-resolution scanning electron microscopy. Form, fit, and function were examined using flow resistance, tensile strength, and particle filtration measurements. A separate examination of filter efficiency, fit, and strap tensile stress measurements was performed by the National Personal Protective Technology Laboratory. Data from these metrological examinations provide evidence that N95 FFR disinfection and reuse using the UV-C enclosure can be effective.