Read the entire document here.

In summary, their process involved: [1]

  • A dedicated lab room equipped to uniformly disperse hydrogen peroxide vapor (35% solution)
  • Exposing ~100 3M 1860 N95 respirators to the HP vapor flow for 25 minutes then letting them “dwell” for another 20 minutes

Researchers also included bio indicators in the room (G.stearothermophilus) to validate decontamination

  • Pumping fresh air into the room to accelerate H2O2 to O2+water conversion
  • Monitoring room air toxicity until acceptable to enter (~4 hours)
  • “Smell testing” masks for H2O2
  • Inspecting masks to ensure physical integrity
  • Fit testing masks on two subjects with differing facial sizes/structures
  • Process repeated.

“Healthcare workers must be equipped with the appropriate PPE that they need to do their jobs with confidence. In times of global shortages, we have to improvise and adapt existing technologies for new uses,” researchers wrote. “We believe that decontamination of N95 respirators with Hydrogen Peroxide Vapor is one such solution that affords us better ability to protect our healthcare workers as we continue to tackle this monumental issue.” [1]

Source:
1. Schwartz A, et al. “Decontamination and Reuse of N95 Respirators with Hydrogen Peroxide Vapor to Address Worldwide Personal Protective Equipment Shortages During the SARS‐CoV‐2 (COVID‐19) Pandemic.” Duke University and Duke University Health System Occupational and Environmental Safety Office (OESO). Accessed https://www.safety.duke.edu/sites/default/files/N-95_VHP-Decon-Re-Use.pdf

Additional Links:

https://www.drugs.com/news/n95-face-masks-can-sterilized-re-studies-show-89268.html

https://www.safety.duke.edu/sites/default/files/N-95_VHP-Decon-Re-Use.pdf