Practical considerations for Ultraviolet-C radiation mediated decontamination of N95 respirator against SARS-CoV-2 virus

PLoS One. 2021 Oct 12;16(10):e0258336. doi: 10.1371/journal.pone.0258336. eCollection 2021.

Abstract

Decontaminating N95 respirators for reuse could mitigate shortages during the COVID-19 pandemic. Although the United States Center for Disease Control has identified Ultraviolet-C irradiation as one of the most promising methods for N95 decontamination, very few studies have evaluated the efficacy of Ultraviolet-C for SARS-CoV-2 inactivation. In addition, most decontamination studies are performed using mask coupons that do not recapitulate the complexity of whole masks. We sought to directly evaluate the efficacy of Ultraviolet-C mediated inactivation of SARS-CoV-2 on N95 respirators. To that end we created a portable UV-C light-emitting diode disinfection chamber and tested decontamination of SARS-CoV-2 at different sites on two models of N95 respirator. We found that decontamination efficacy depends on mask model, material and location of the contamination on the mask. Our results emphasize the need for caution when interpreting efficacy data of UV-C decontamination methods.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Decontamination* / instrumentation
  • Decontamination* / methods
  • Disinfection* / instrumentation
  • Disinfection* / methods
  • Equipment Reuse
  • Masks*
  • N95 Respirators*
  • Ultraviolet Rays*

Grants and funding

This work was funded by Fast Grants (part of Emergent Ventures at George Mason University) to SAS. AWR is an Open Philanthropy Fellow of the Life Sciences Research Foundation. Authors CC, SR, AMD, DLW and JPC are employees of Verily Life Sciences. Authors JZ, YG, LZ are employees of Bolb, Inc. Author MK is President at Arkesso, LLC. The funders provided support in the form of salaries for authors CC, SR, AMD, DLW, JPC, JZ, YG, LZ, MK and support in the form of work hours and equipment for the authors to execute and collaborate in the study design, data collection and analysis. The funders permitted authors to proceed with the decision to publish, or preparation of the manuscript.