AAMI presented a webinar on May 4, 2020 in which representatives from 3M, Steris, ASP, Sterilucent, and Battelle discussed the CDC strategies for N95 use and Emergency Use Authorizations (EUAs) granted by the FDA regarding the decontamination of N95 respirators. The presentation was based on US regulations as they stand in May 2020.
The speaker from 3M discussed the hierarchy of strategies the CDC outlines with respect to the way respirators are used. The hierarchy is as follows: use of other respirator types, extended use of N95s (not discarding after every use), N95 use past their shelf life, placement in a breathable bag and allowed to sit for five days before reusing, and lastly, decontamination of N95s. The first strategy falls under the tier of “conventional capacity” (everyday use), the second strategy falls under the tier of “contingency capacity” (expected shortage), and the three final strategies fall under “crisis capacity” (known shortage). Although the CDC emphasizes that decontamination of N95s should be the last resort, the COVID-19 pandemic has induced an incessant demand and a shortage, introducing the need for decontamination. The most promising decontamination methods are vaporized hydrogen peroxide, ultraviolet germicidal irradiation, and moist heat. The 3M representative discussed that it should be the manufacturers that determine which method should be used with their specific manufactured N95, and that there are four factors that determine if a certain decontamination method works: efficacy (the method must inactivate the virus), safety (safe for the wearer), filtration (method must not damage filtration), and fit (must maintain sealing ability). Based on these four factors, 3M has determined four methods to be effective: the three methods listed above, vaporized hydrogen peroxide, ultraviolet germicidal irradiation, and moist heat, in addition to environmental vaporized hydrogen peroxide. They have determined two possibly suitable methods: microwave-generated steam and liquid hydrogen peroxide, and have recommended AGAINST eight methods: autoclaving, dry heat, isopropyl alcohol, soap, dry microwave irradiation, chlorine bleach, disinfectant wipes, and ethylene oxide.
The webinar continued with representatives from Steris, ASP, Sterilucent, and Battelle, companies specializing in sterilization who have received EUA from the FDA. Each representative addressed what their approaches have been and continue to be during the COVID-19 pandemic.
The webinar can be viewed at https://www.youtube.com/watch?v=lYxuH7weYlA.
The CDC strategy hierarchy can be found at https://www.cdc.gov/niosh/topics/hcwcontrols/recommendedguidanceextuse.html.