Study finds N95 respirator masks can be decontaminated using a rice cooker or Instant Pot

A new study from the University of Illinois, Urbana-Champaign, has looked at a new method of sanitizing N95 respirator masks using common home appliances. The study found that placing an N95 respirator into a cooker, such as a rice cooker or Instant Pot, that produces dry heat for 50 minutes, will decontaminate the masks inside and out. At the same time, the sanitation method also preserves the filtration and fit of the masks.

The researchers say that this sanitation method could enable wearers to safely reuse limited supplies of the respirators that were originally meant to be one-time use items. N95 masks are highly prized during the coronavirus pandemic. Not only can it protect others from droplets, the wearer might expel but also protect the wearer by filtering out smaller particles that might carry the virus.

These respirators have been in very short supply since the pandemic started. The researchers say that there are many different ways to sterilize something but most methods destroy the filtration or fit of the N95 respirator. The team had hypothesized the dry heat might be a method that could decontaminate the masks while maintaining the filtration and fit without requiring special preparation or leaving a chemical residue.

Researchers also had a goal of finding a method that was widely accessible to people at home. Researchers verified that with one cycle of their test model's rice-cooking preset sanitized the mask. The setting maintains the cooker's contents at around 100-degrees Celsius was able to decontaminate the mask over 50 minutes inside and out. The Sanitation method is effective on four different virus classes, including the coronavirus, and was found to be more effective than ultraviolet light.

After sanitation, the team tested the respirators and found they maintain the filtration capacity of more than 95% and kept their fit. The masks were able to perform appropriately after 20 cycles of decontamination in the electric cooker.