In the midst of the coronavirus pandemic, face masks are an everyday sight. But a new high-tech mask designed by researchers at the Massachusetts Institute of Technology looks anything but everyday.
In the slightly dystopian reality that is the year 2020, a team of MIT researchers has gone beyond the ubiquitous N95 mask. The team has designed a mask that uses a heated copper mesh to sanitize the air on contact. If it stands up to real-world testing, it could equate to a millionfold reduction in virus particles. It also makes the wearer look a little like Bane.
The aggressive look for the mask is partially due to its technology that heats the air near the wearer's face to 194 degrees Fahrenheit.
All of which begs the question: Can anyone actually wear this thing?
Much like a pair of boots, odds are you've tried a couple of different masks out for size to try to find a favorite. Among the most-common masks are single-use surgical masks, N95 masks, or reusable cotton ones. All three types are scientifically proven to limit the spread of Covid-19, but they aren't without limitations, these scientists say. They detailed their new design and why it works in a paper published on ArXiv, a preprint site. The paper has not yet been peer-reviewed and published in a journal.
"Mask shortages, the generation of waste from single-use facemasks, and the spread of the COVID-19 pandemic to regions of the world with weaker healthcare infrastructure present an urgent need to reconsider designs and concepts for protective face masks," the scientists write in the paper.
The inspiration for the mask came close to home. When MIT started to shut up shop in March, Michael Strano, professor of chemical engineering at MIT, and his graduate student Samuel Faucher decided to get busy. Both researchers are authors on the paper. Together, they turned to older studies in search of ideas to create a next-gen face mask.
"[T]here [was] no one really thinking about inactivating the virus and sterilizing the air," Strano explains in a statement. "That surprised me."
Strano and his team set out to design a mask that would not simply defend the user and others against Covid-19, but could actually stop the spread of virus particles entirely.
"Being able to breathe in medically sterile air and breathe out medically sterile air... is just the next step. It’s better technology.”
Designing the mask — The mask they came up with is pretty different to your typical three-layer mask. It includes a heating element and a copper-mesh screen. The idea here is that when air from the outside is brought in through the mask, it passes through a heated copper mesh. Copper is known for its antiviral and antibacterial properties, as it essentially creates an environment on which these germs cannot thrive. And inversely, air breathed out by the wearer is passed through the heated element for sanitation, before passing into the open air.
Faucher said in a statement that this "thermal inactivation" approach is unlike any other filtration mask on the market.
Based on their models, which have not yet been clinically tested, the reachers estimate that their masks would result in a thousandfold to a millionfold decrease in virus particles. Plus, because of the cyclical nature of human breath, the researchers say that particles may get passed through the copper mesh more than once, improving their likelihood of being fried.
Because of all the hardware it involves, the facemask design is a little chunky. It looks like it might be more at home in the world of Mad Max than the streets of Cambridge.
But size is important for more than accommodating the hardware. It also helps strike a fine balance between airflow and CO2 build up. The 300mL design they settled on is the sweet spot that ensures both good airflow and safe dispersion of CO2, the researchers write in the paper.
Safety first — Still the question remains: how can something so hot that it disintegrates virus cells on contact sit safely on your face?
To address this issue, the researchers used a type of ultra-insulating material called neoprene, which is heat resistant up to a scalding 275 degrees Fahrenheit. When the copper heats, the neoprene would insulate the user. At the same time, the air they are breathing in would — theoretically — be cooled enough to be comfortable.
"Better technology" — This mask is not hitting stores any time soon. The design needs to be tested in the lab and the real world to establish how well they actually perform in the wild on human volunteers. But the researchers are optimistic that a design like this — or perhaps one that safely included sterilizing UV light — could herald a new era of innovation for this essential protective equipment.
“What we show is that it's possible to wear something on your face that’s not too cumbersome, that can actually allow you to breathe medically sterile air,” Strano said. “The prospect of being able to breathe in medically sterile air and breathe out medically sterile air, protecting the people around you and protecting yourself, is just the next step. It’s better technology.”
Preprint Abstract: While facial coverings over the nose and mouth reduce the spread of the virus SARS-CoV-2 by filtration, masks capable of viral inactivation by heating could provide a complementary method to limit viral transmission. In this work, we introduce a new virucidal face mask concept based on a reverse-flow reactor driven by the oscillatory flow of human breath. The governing heat and mass transport equation are formulated and solved to analyze designs that evaluate both viral and CO2 transport during inhalation and exhalation. Given limits imposed by the volume and frequency of human breath, the kinetics of SARS-CoV-2 thermal inactivation, and human safety and comfort, heated masks may inactivate SARS-CoV-2 in inflow and outflow to medical grade sterility. We detail one particular design, with a volume of 300 mL at 90 °C, that achieves a 3-log reduction in viral load with minimal viral impedance within the mask mesh, with partition coefficient around 2. This study is the first quantitative analysis of virucidal thermal inactivation within a protective face mask and addresses a pressing need for new approaches for personal protective equipment during a global pandemic.