Now researchers at Duke University have developed a method to clean them so that they can be worn safely again.
With vaporized hydrogen peroxide, the researchers can kill microbial contaminants lurking on the masks after wearing them.
It’s a way that labs have been decontaminating equipment for decades, said Wayne Thomann, emeritus director of the Duke Occupational & Environmental Safety Office.
But the team never thought it would be needed for face masks.
Decontamination requires special equipment in a closed system to deal with hydrogen peroxide. However, the process has already been carried out in Duke Health hospital complexes and can also be carried out in other hospitals.
Previous research has shown that respirators can be decontaminated 30 to 50 times and worn again. However, Thomann and the team at the Biocontainment Laboratory are still testing how often they can be worn again after treating coronavirus patients.
“It will certainly be less than 30 and we will be conservative to ensure performance and security,” said Thomann CNN in an email.
The masks tolerate decontamination well, he said, so the process doesn’t damage them or make them less effective.
Before the breathing masks are redistributed, the team examines them for tears to ensure that they have not lost their shape. You need to sit tight and cover your entire mouth to be effective.
And when doctors and nurses are sick, fewer people have to care for the patients.
Decontamination keeps doctors safer in the fight against coronavirus and strengthens hospitals’ efforts to treat patients, Thomann said.
“The N95 ventilator is the most suitable respiratory protection for the caregiver of patients caring for Covid-19 patients, particularly in aerosol-producing procedures in these patients,” he told CNN. “The reprocessing helps us ensure that they have the best PPE to protect them.”