Studies identify a more rapid method to decontaminate N95 masks

Two Rutgers-led studies have identified a more rapid method to decontaminate N95 masks using vaporized hydrogen peroxide – making reuse of masks more economically feasible and practical for health care workers on the frontlines against COVID-19.

The studies, published in the journal MedRxiv, also found that after eight rounds of decontamination, some models of N95 masks, including the Halyard Fluidshield 46727 model, provided inadequate protection for re-users.

Mask decontamination and reuse at a large scale have become increasingly important in the health care industry due to shortages of personal protective equipment (PPE) during the COVID-19 pandemic.

Current methods used to decontaminate N95 masks require bigger spaces, longer times and a lot of personnel to hang as few as 250 masks in 30 minutes individually. The new method we found nearly tripled the number of masks disinfected using the same space and time, showing the efficiency and rapidness of our new proposed approach."

Riccardo Russo, Director of BSL3 Operations at Rutgers New Jersey Medical School

Unlike current methods that hang individual masks to be disinfected, the new way of stacking masks on racks in piles didn't interfere with decontamination, took up less space and reduced the hands-on time needed now by almost 67 percent.

The studies found that used masks could be fully decontaminated even if they contained large amounts of makeup, moisturizer or both. They also found that masks could be decontaminated in individually labeled paper bags, enabling easy identification of personal masks after disinfecting. It will also be important for health care facilities that decontaminate masks to preserve PPE so individual masks can be returned to their previous owners.

"Per our findings, it's important to emphasize that every mask's make and model need to be carefully evaluated before it is deemed safe for vaporized hydrogen peroxide decontamination and reuse," said co-author Carly Levine, a graduate student at Rutgers NJMS.

David Alland, director of the Public Health Research Institute and the Center for COVID-19 Response and Pandemic Preparedness at Rutgers NJMS, and Courtney Grady, a graduate student at Rutgers NJMS were co-authors of the studies.