Own an electric multicooker? It may be able to serve a noble purpose: properly decontaminating N95 respirators without compromising fit and function, according to researchers from the University of Illinois, Urbana-Champaign. 

Face mask ready for decontamination in electric cooker

Successful decontamination requires one cooking cycle, or 50 minutes of dry heat, at 212℉ in an electric cooker (such as a rice cooker or an Instant Pot), the study team found. The method decontaminated N95 respirators inside and out, killing four different classes of virus — including a coronavirus — and was more effective than ultraviolet light, they said.

Filtration and fit also were examined. “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,” said Vishal Verma, Ph.D. “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.”

Several respirators can be stacked on top of a towel placed in the cooker, to prevent them from touching the pot directly. The researchers have made a YouTube video demonstrating the method.

Most sterilization techniques destroy the filtration or the fit of these high-performance respirators, Verma said. “Any sanitation method would need to decontaminate all surfaces of the respirator, but equally important is maintaining the filtration efficacy and the fit of the respirator to the face of the wearer. Otherwise, it will not offer the right protection.”

One of the greatest benefits of the discovery is that many people and institutions may already have the equipment on hand, Verma added.

The study was published in the journal Environmental Science and Technology Letters.