N95 respirator masks, used to protect against the novel coronavirus, among other diseases, can be decontaminated by placing them in a rice cooker or Instant Pot for 50 minutes, according to a study out of the University of Illinois, Urbana-Champaign.
The N95 respirators are considered the gold standard of personal protective equipment when it comes to protection from airborne particles and droplets, according to health experts.
The masks, when placed in dry heat in an electric cooker, maintained their filtration capability and fit and were cleaned inside and out, according to the study published in the journal Environmental Science and Technology Letters. The findings suggest this may allow wearers to safely reuse the respirators, which are typically intended for one-time use.
“A pandemic such as COVID-19 can cause a sudden depletion of the worldwide supply of respirators, forcing health care providers to reuse them,” the researchers stated in the study.
The researchers found that when the masks were placed through one cycle in a rice cooker maintained at about 212°F for 50 minutes, the N95 respirators were decontaminated inside and out, from four different classes of the virus, including a coronavirus. The researchers stated in a news release that it was more effective than ultraviolet light against the virus, and noted that the masks’ filtration and fit remained intact.
“We built a chamber in my aerosol-testing lab specifically to look at the filtration of the N95 respirators, and measured particles going through it,” stated Vishal Verma, a civil and environmental engineering professor and co-author of the study, in a news release. “The respirators maintained their filtration capacity of more than 95% and kept their fit, still properly seated on the wearer’s face, even after 20 cycles of decontamination in the electric cooker.”
The researchers warned that no water should be added to the cooker, and the heat must be a dry heat. They instructed placing a small towel to cover the bottom of the cooker to avoid the N95 mask coming into contact with the heating element and noted that multiple masks can be stacked to fit inside the cooker at the same time.
“On the basis of these results, dry heat decontamination generated by an electric cooker (e.g., rice cookers, Instant Pots and ovens) could be an effective and accessible decontamination method for the safe reuse of N95 respirators. We recommend users measure the temperature during decontamination to ensure the respirator temperature can be maintained at 100°C [212°F] for 50 minutes,” the study authors wrote.
The electric-cooker method can be useful for health care workers and first responders, especially those in smaller clinics or hospitals that do not have access to large-scale heat sanitization equipment, the researchers stated in the release. For a video of the method, click here.