There has been a good deal of discussion recently about how critical PPEs, especially N95 masks, could be decontaminated for reuse. A news release today from Duke Health and the Duke University Hospitals brings good news on that front. They have tested a method first explored in 2016 that can decontaminate masks without degrading either their materials or their fit, both crucial to the successful reuse of the masks.
The method uses vaporized hydrogen peroxide to perform the decontamination. This is not a new technology, but rather a re-purposing of an already existing decontamination technique to a new application. This has several advantages, the most obvious being that the tools already exist and have been being manufactured for some time for use in biocontainment labs. So no lag in getting the necessary equipment out to at least some hospitals that have been using this already. There is also the possibility that other labs might have this equipment and can loan or donate it to hospitals that will need to use it for mask decontamination.
“This is a decontamination technology and method we’ve used for years in our biocontainment laboratory,” said Scott Alderman, associate director of the Duke Regional Biocontainment Laboratory.
“We had never considered needing it for something like face masks. But we’ve now proven that it works and will begin using the technology immediately in all three Duke Health hospitals,” said Matthew Stiegel, Ph.D., director of the Occupational and Environmental safety Office.
The critical idea is that this is a safe and proven decontamination method that is available now. All that was needed was the testing to prove that it could work in the real world.
The use of hydrogen peroxide to decontaminate N95 masks was tested and published by others in 2016, but did not result in widespread adaptation. The earlier studies did not include fit testing after cleaning – basically sizing the masks for individual wearers - to prove efficacy in the real world, which Duke has now done.
The decontamination process requires specialized equipment that aerosolizes the hydrogen peroxide, and a closed facility where the masks can be exposed to the vapor. No toxic byproducts result, because hydrogen peroxide breaks down to water.
This is the kind of breakthrough that we’ve been needing to stave off the worst shortages in PPE. Duke is now working to disseminate the protocols widely so that as many hospitals as possible can start to reuse N95 masks, and possibly other PPE items as well. This won’t solve the problems of equipment supply entirely, but it will take some of the pressure off the supply systems and let them have time to attempt to catch up. Even reusing masks only 2 or 3 times would be a significant help, one that could end up saving health care professionals and their patients from infection.