Aerosolized Hydrogen Peroxide Decontamination of N95 Respirators, with Fit-Testing and Virologic Confirmation of Suitability for Re-Use During the COVID-19 Pandemic

T. Hans Derr; Melissa A. James; Chad V. Kuny; Prem P. Kandel; Matthew D. Beckman; Kevin L. Hockett; Mark A. Bates; Moriah L Szpara

Prior to decontamination, respirator facepieces were inoculated with a controlled amount of one or more surrogate virus species (see Table 2 for full list). Each virus was added in duplicate droplets of 10 µL each, on one or more surfaces of each respirator type. Droplets were allowed to air-dry or absorb onto each respirator in the open air flow of a biosafety cabinet. A sample of each virus-spotted facepiece was removed and left open to air, but without aHP decontamination, as a "dried" virus control. The remainder of each facepiece was subjected to aHP decontamination as described above (i.e. the "decontaminated" virus). After aHP, respirators were confirmed to have <1 ppm H2O2 before being transferred from the decon room to a cell culture facility for virus titration. At this stage each virus-inoculated location was sliced out of the "dried" or "decontaminated" respirators using dissection scissors. Each excised virus-spot encompassed all layers of the respirator, to capture any virus that had soaked below the surface fabric. Virus-inoculated respirator pieces were transferred into individual Eppendorf tubes and . CC-BY-NC-ND 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.