By Courtney Linder
With face masks here to stay for the long haul, that means you’ll have to wash them consistently like any other piece of clothing—and disinfect them, too. But if you don’t have access to a washing machine to clean your cloth covering, now you have another option: rice cookers and instant pots.
Researchers from the University of Illinois, Urbana-Champaign conducted a series of lab tests using the multipurpose appliances and found that as long as you “cook” the masks at a temperature of at least 100 degrees Celsius for 50 minutes, the method can inactivate four classes of virus, including a type of coronavirus.
The scientists published their results last month in the journal Environmental Science and Technology Letters.
“There are many different ways to sterilize something, but most of them will destroy the filtration or the fit of an N95 respirator,” Vishal Verma, an assistant professor of civil and environmental engineering, said in a prepared statement. “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.”
In this case, the scientists used N-95 respirators, a type of personal protective equipment (PPE) that fits tightly to the face and filters out 95 percent of the particles in the air. Due to a shortage of PPE, health care workers have been reusing their masks and respirators, so a robust method for disinfecting them is vital.
In washing machines, however, masks can become warped. That impacts a mask’s fit, and therefore, filtration. The researchers hypothesized that the dry heat used in rice cookers and instant pots could hit a trifecta for fit, filtration, and decontamination.
To test their theory, the scientists put N-95 masks in an instant pot and set the cycle to a rice-cooking preset option that maintains the contents of the cooker at about 100 degrees Celsius, or 212 degrees Fahrenheit. Maintaining that heat for 50 minutes, the team was able to disinfect the masks of four different classes of viruses better than ultraviolet light, which inactivates the genetic material inside a virus, causing it to drop dead.
The scientists built a special chamber in Verma’s aerosol-testing lab to examine the filtration capability of the N-95 respirators after running them through the rice cooking cycle, measuring how many particles could get through them.
“The respirators maintained their filtration capacity of more than 95 percent and kept their fit, still properly seated on the wearer’s face, even after 20 cycles of decontamination in the electric cooker,” Verma said.
If you want to try out this method for yourself, keep these tips in mind:
→ Dry heat is essential—you should not add any water to the cooker. You must maintain the temperature at a minimum of 100 degrees Celsius, for at least 50 minutes.
→ Fold up a dry towel and place it along the bottom of the cooker to keep the mask from touching the sides of the dish. Because the surface of the pot is hotter than the melting point of the masks, you must keep them from coming into direct contact.
→ You may place multiple masks in the pot at the same time as long as they don’t touch the sides and you can still fit the lid on top.
It’s important to note the scientists only tested out this method on an instant pot and a rice cooker. If you want to use a similar household appliance—perhaps a crockpot or a pressure cooker—make sure you’re meeting the criteria above.
Sources : popularmechanics.com