An add on to its many other benefits, electric multicookers can also be used to sanitize N95 respirator masks, according to a recent study.
The University of Illinois, Urbana-Champaign study found that 50 minutes of dry heat in an electric cooker, such as a rice cooker or Instant Pot, decontaminated N95 respirators inside and out while maintaining their filtration and fit. This could enable wearers to safely reuse limited supplies of the respirators, originally intended to be one-time-use items.
Led by civil and environmental engineering professors Thanh Helen Nguyen and Vishal Verma, the researchers published their findings in the journal Environmental Science and Technology Letters.
N95 respirator masks are the gold standard of personal protective equipment that protects the wearer against airborne droplets and particles, such as the coronavirus that causes COVID-19.
“A cloth mask or surgical mask protects others from droplets the wearer might expel, but a respirator mask protects the wearer by filtering out smaller particles that might carry the virus,” Nguyen said.High demand during the COVID-19 pandemic has created severe shortages for health care providers and other essential workers, prompting a search for creative approaches to sanitization.
“There are many different ways to sterilize something, but most of them will destroy the filtration or the fit of an N95 respirator,” 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,” the researcher added.
The researchers hypothesized that dry heat might be a method to meet all three criteria – decontamination, filtration, and fit – without requiring special preparation or leaving any chemical residue. They also wanted to find a method that would be widely accessible to people at home. They decided to test an electric cooker, a type of device many people have in their pantries.
They verified that one cooking cycle, which maintains the contents of the cooker at around 100 degrees Celsius or 212 Fahrenheit for 50 minutes, decontaminated the masks, inside and out, from four different classes of the virus, including a coronavirus – and did so more effectively than ultraviolet light. Then, they tested the filtration and fit.