On April 18, 2022, a Florida judge overturned the federal mandate requiring passengers to wear masks on mass transit. While the U.S. Centers for Disease Control and Prevention continues to recommend that passengers wear masks on airplanes, trains, or buses, it is no longer a requirement. When asked if people should wear masks on planes, President Joe Biden replied, “It’s up to them.”
The conversation covers the science of masks since the beginning of the pandemic. Masking may no longer be necessary during mass transit, but you can always choose to still wear a mask. For those concerned about exposure to SARS-CoV-2 or developing COVID-19, below are highlights from four articles exploring the benefits of wearing a mask and how to get the most protection from one to wear.
1. Masks can protect the person wearing them
Many of the reasons for wearing a mask are to protect others. But early in the pandemic, Monica Gandhi, a professor of medicine at the University of California, San Francisco, explained how masks can also protect the wearer.
“If you wear a mask – even a cloth mask – you are usually exposed to a lower dose of the coronavirus than when you did not,” Gandhi writes. “Both recent experiments in animal models using coronavirus and nearly a hundred years of viral research show that lower viral doses usually mean less serious diseases.”
Although this is just one of many factors, “the amount of virus you are exposed to – called the viral inoculum or dose – has a lot to do with how sick you become. If the exposure dose is very high, the immune response can be overwhelmed, ”Gandhi explains. “On the other hand, if the initial dose of the virus is small, the immune system is able to contain the virus.”
Read more: Material masks protect the wearer – if you inhale less coronavirus, you become less ill
The better the mask, the lower the exposure dose. And in the many months since Gandhi wrote that story, a lot of work has been done to determine what kind of masks are most effective.
2. What makes a good mask?
The first thing to consider when wearing a mask is whether it is a good one. Christian L’Orange is a professor of mechanical engineering and has been testing various masks for the state of Colorado since the beginning of the pandemic. He explains that there are two things that make a protective mask. “Firstly, there is the ability of the material to capture particles. The second factor is the fraction of inhaled or exhaled air that leaks around the mask – essentially how well a mask fits. ”
When it comes to these two features, says L’Orange, “the N95 and KN95 masks are the best option.” This achievement has a lot to do with the materials from which they are made. “These fibers are packed very tightly so that the gaps through which a particle has to navigate are very small. This results in a high probability that particles will eventually touch a fiber and adhere to a fiber when they pass through a mask. These polypropylene materials also often have a static charge that can help attract and trap particles. ”
Fitness is the second most important factor for a mask. As L’Orange writes, “a mask can only provide protection if it does not leak.” N95s and KN95s are tight and seal much better than other masks.
If you do not have access to an N95 or KN95, surgical masks should be your second choice. They are made of densely woven material, but they do not seal perfectly. Cloth masks should be your last choice because of their generally loose fabric and poor fit. But there are ways to improve the performance of surgical and cloth masks.
Read more: What is the best mask for COVID-19? A mechanical engineer explains science after 2 years of testing masks in his laboratory
3. How to make a mask fit well
“No matter how good a mask’s material is, it will not work well if it does not fit well,” writes Scott Schiffres, a mechanical engineer at Binghamton University.
There are two ways to improve the fit and performance of surgical and cloth masks. The first, Schiffres explains, simply wears two masks. “Double masking is wearing a cotton mask over a medical procedure mask.” This can significantly improve the fitness and add a little more filtration. The second approach is to knot and insert a surgical mask so that it fits better.
As Schiffres explains in his article, “Knot and stitch involves tying a knot in the elastic loops that go over your ears, close to where they attach to the mask. Then you stitch the extra mask fabric into the gap that is often present where attach the ruffles to the mask, flattening that part as much as possible.Both of these tricks fit better and reduce the mask wearers’ exposure to potentially infectious aerosols by 95% compared to wearing no mask.This is an improvement of 15% above the 80% efficacy found when using a single surgical mask.
Read more: CDC says masks should fit snugly – and two is better than one
4. Breakthrough cases and new variants
The last consideration when deciding to wear a mask is not about you. In this way others can be protected.
Sara Sawyer, Arturo Barbachano-Guerrero and Cody Warren are virologists and biologists at the University of Colorado Boulder. In a recent story, they write that omicron “is often able to evade existing immunity long enough to start an infection, cause symptoms, and transmit it to the next person.” “This explains why re-infections and breakthrough infections through vaccine are more common with omicron.”
Case numbers are low for now, and so the risk of catching or transmitting the coronavirus is too. But it is not zero; some places have a higher risk than others, and new variants can come quickly. As the team writes, all new variants that are widely distributed – so-called variants of concern – are likely to be highly communicable.
Read more: Alpha then delta and now omicron – 6 questions answered as COVID-19 cases increase worldwide again
The person next to you on the plane may not be wearing a mask and, as it stands now, it is their choice to make. If you want to reduce your own chances of catching or spreading the coronavirus, there are still a number of reasons to wear a high quality fitting mask.
Editor’s note: This story is a summary of articles from The Conversation’s archives.