The process aims to relieve shortages by using vaporised hydrogen peroxide to kill pathogens without degrading the masks
Facing a critical shortage of N95 face masks that block the coronavirus, Duke Health research and clinical teams have confirmed a way to use existing vaporised hydrogen peroxide methods to decontaminate the masks so they can be reused.
The process uses specialised equipment to aerosolise hydrogen peroxide, which permeates the layers of the mask to kills germs, including viruses, without degrading the mask material.
“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, Director of the Occupational and Environmental Safety Office.
The decontamination process should keep a significant number of N95 masks in use at Duke University Hospital as well as Duke Regional and Duke Raleigh hospitals, easing some of the shortage and curbing the need for other alternatives using unproven decontamination techniques.
The ability to reuse the crucial N95 masks will boost the hospitals’ ability to protect frontline health care worker
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 specialised equipment that aerosolises the hydrogen peroxide, and a closed facility where the masks can be exposed to the vapour. No toxic byproducts result, because hydrogen peroxide breaks down to water.
“The ability to reuse the crucial N95 masks will boost the hospitals’ ability to protect frontline health care workers during this time of critical shortages of N95 masks,” said Cameron Wolfe, Associate Professor of Medicine and infectious disease specialist.
Monte Brown, VP at Duke University Health System, said the Duke team is working to spread the word about the technique, making the protocols widely available. He said several health systems and many pharmaceutical companies already have the needed equipment, which is currently used in different ways, and could ramp up operations to come to the aid of their local hospitals.
“We could stand up in front of our staff and state with confidence that we are using a proven decontamination method,” Brown said. “It has been a proven method for years. While this alone will not solve the problem, if we and others can reuse masks even once or twice, that would be a huge benefit given the current shortages.”