N95 respirators have been at the forefront of this pandemic since the very beginning. Potential shortages, scams, increase in demand and production, and a lot of other issues have risen up as a consequence of the COVID-19 pandemic. This type of disposable face mask is extremely valuable right now, especially for healthcare workers.
One of the main issues with these face masks is that they’re disposable face masks, meaning they’re not reusable. A lot of the research being done at the moment involving N95 masks revolves around the idea of either designing a reusable N95 respirator or a way to sterilize them to be reusable. Both of these goals are tricky because they need to be done in a way in which the antiviral filtrating properties of the face mask are not eliminated.
Today, we bring you the latest breakthrough in terms of sterilizing N95 masks, and it only involves an electric cooker.
How to clean N95 respirators with an electric cooker
An incredible breakthrough was made in a study run by the University of Illinois called Urban-Champaign. According to their results, electric cookers, also called multi cookers, can be the domestic electronic device to solve the problem of N95 mask scarcity that has been going on since the beginning of the pandemic.
The study found that dry heating for 50 minutes inside electric cookers, which can be a wide variety of items like rice cookers or an Instant Pot, is enough to completely sterilize N95 masks without messing with the mask’s filtrating capacities. This could potentially mean that disposable N95 masks can be reused safely while shortages and scarcity has made them a limited supply.
The study was led by Thanh Nguyen and Vishal Verma, two civil and environmental engineering professors. According to them, N95 respirators are the main piece of personal protective equipment against any airborne particle, and right now we are facing one big airborne particle: the coronavirus. That’s why they’ve been focusing particularly on this disposable face mask.
The researchers stated that, while sterilizing an item is relatively easy and there are many ways to do it, most of these methods destroy the filter or change the fit of the face mask. So, this is the main problem they were trying to solve. How could they completely decontaminate the respirators but still maintain its virus protection properties?
Their first hypothesis was that sterilization with dry heat would be the best shot at obtaining the desired results, without the need to repair the respirator afterwards. Another big point they were focusing on was accessibility for everyone, since this is an emergency situation. For all these reasons, they decided to test electric cookers, which is widely accessible for regular people and most already have one at home.
The cooking cycles were around 100 degrees Celsius during 50 minutes, and they showed complete inside and out decontamination of the masks from 4 types of virus, including SARS-CoV-2, the virus that causes COVID-19. Once they were sure the masks were decontaminated, it was time to test the filtration capacities and the fit.
To test this, they built a chamber in an aerosol-testing lab, and measured the particulates that were going through the mask. The results showed that the N95 respirators were maintaining their 95% minimum filtration efficacy, and they still fit properly around the face, sealing the wearer’s mouth and nose. These results were the same even after 20 cycles.
To instruct people at home, they created a video where they demonstrated their method. Some key points they clarified in the video include that the heat must be dry, so no water or any other liquid should be added to the cooker, the temperature needs to be constantly at 100 degrees Celsius during 50 minutes. To prevent the respirator from contacting the heating element, a towel should be covering the bottom of the cooker. This way, multiple masks can be inside the cooker and sterilized at the same time.
The people behind this breakthrough are hopeful that this new method will be especially useful for healthcare workers, particularly those in smaller attention centers that don’t always have access to PPE.
The importance of N95 masks right now
N95 masks are a particular type of disposable face mask. They are the optimal way to protect ourselves from non-oil based particles, such as smoke, dust, and viruses, including the SARS-CoV-2 or the flu. Their filter is capable of trapping at least 95% of all airborne particles in the air, which are particles with a diameter of 0.3 microns.
The National Institute for Occupational Safety and Health, also known as NIOSH, has a classification for respirators, based on their standards. This classification takes into consideration mainly two features: resistance to oil and the percentage of minimum particulate filtration efficacy. According to this classification, N95 respirators are not resistant to oil, indicated by the letter ‘N’, and have a minimum particulate filtration efficacy of 95%, indicated by the number ‘95’.
These masks are very useful, especially right now. They’ve been used as PPE for decades in many work fields where workers are vulnerable to work-related diseases from respiratory hazards. These industries include mining, painting, and construction, but also the healthcare field.
Any respirator manufactured and marketed as an N95 respirators must meet the standards set by NIOSH and be approved by them, otherwise they’re not safe to be used since they won’t offer the same protection. To be used as medical or surgical PPE, in addition to the NIOSH approval, the respirators need also approval by the Food and Drug Administration (FDA).
Shortages in the United States are a reality, but there are many ways to buy PPE for sale online, in bulk or wholesale. You can easily find face shields, KN95 masks, and 3M N95 masks in models like the 3M 8511 or 3M 8210, and even face masks in a smaller size for kids. Make sure to stay protected.