Back in March, when COVID-19 restrictions were being put in place in Massachusetts, I tried to buy some face masks, but they were sold out everywhere. After a month or so of rationing the few surgical masks I had managed to scrounge up, the first reusable cloth mask I preordered came in the mail. But it didn’t fit well, leaving gaps around my nose and by my ears. I’ve been on the hunt for the perfect face mask ever since.
You’re probably wondering, is there a perfect face mask? We had the same question, so we put more than a dozen masks to the test. But first, let’s say this: There are many cloth face masks available. We knew we couldn’t test them all, so we asked our America’s Test Kitchen colleagues what masks they have and what they like and don’t like about them. We then narrowed our scope to 14 masks, priced from about $9 to $70, and made from a variety of materials, shapes, and styles.
To see which masks were protective, simple to put on, comfortable to wear, and easy to clean, we put them through a host of tests: taking them on and off repeatedly; seeing if we could blow out a candle while wearing them (a basic barrier efficacy test); walking and running while wearing them; having users of different face shapes, sizes, and features try each mask on; and washing the masks after each use. We also used a thermal imaging camera to see where heat (aka our breath) was escaping through each mask.
Yes! A mask’s material definitely contributes to its effectiveness. To find out why, we spoke with Kim Trautman, executive vice president of medical device international services for the NSF International. Our masks were made from natural fibers (such as cotton and linen), synthetic fibers (such as polyester, silicone, and spandex), or both. Trautman said that masks made from natural fibers filter particles better than those made with synthetic fibers because natural fibers are more irregular in shape. Synthetic fibers, she explained, are smoother and organized more uniformly at a microscopic level, resulting in entrances that are easier for particles, especially small ones, to pass through.
Another important point to consider when choosing a mask is how well it balances breathability with filtration. According to Trautman, “Making sure the wearer is comfortable enough to wear [the mask] for long durations without fiddling with it” is very crucial. Tightly woven masks made from natural fibers may not be as breathable as those made from synthetic fibers, so some masks on the market are a mix of natural and synthetic fibers and have multiple layers of fabric. “In general, natural fibers are better, but if you have multiple-layer masks (which I recommend highly, at least a 2- or 3-layer mask), there you can actually blend a natural fiber layer and a synthetic fiber layer, “ Trautman explains, getting the best possible experience of both filtration and breathability.
To see how well the masks theoretically filtered particles (also called barrier efficacy), we put the masks on, adjusted them as necessary so that they fit securely, and then tried to blow out a lit birthday candle. Why the candle test? “It is a very simple way to assess how much barrier efficacy there is,” says Dr. Sarah Fortune, professor of immunology and infectious diseases and chair of the department of immunology and infectious diseases at the Harvard T.H. Chan School of Public Health. We repeated this test after the masks had been washed several times to make sure that long-term use wouldn’t affect the masks’ effectiveness.
The good news: Most of the masks didn’t allow us to blow out the candle, which is a sign that they had sufficient barrier efficacy. The masks that failed this test were noticeably thinner than the others, and the worst performer was made from 100 percent synthetic fabrics. These masks were also often situated closer to our mouths when on, allowing our breath to pass right through. The pleated masks we tried failed the candle test; they also felt thinner and flimsier than the other masks in our lineup. The best performers had multiple layers of fabric made of cotton and synthetic materials, either blended together or layered on top of one another, and allowed for more space between our mouths and the masks where our exhaled breath pooled inside the mask instead of shooting straight out.
We took pictures of ourselves in each mask using a thermal imaging camera to shed some more light on the masks’ effectiveness. The worst performers clearly had “hot spots” showing where breath (and any accompanying germs) were escaping the masks. The best masks more evenly distributed the heat around the inside of the mask when the wearer exhaled, diffusing the oxygen more gently into the surrounding air and thus containing more germs.
We then moved on to testing breathability by walking for 5 minutes and then running for 5 minutes in each mask. All but one of the masks were comfortable to walk in. The one that failed this test had a tight seal and high filtration capabilities, which made it hard to breathe—so much so that one tester remarked while wearing it, “It feels like I’m having an asthma attack.” However, all but four of the masks were uncomfortable to run in, with testers noting that they felt like they were inhaling fabric. Unfortunately, two of the four masks that were comfortable to run in had previously failed the candle test, meaning they didn’t have great filtration. This is all to say: Every mask is likely to have its pros and cons, and we didn’t find a mask that was perfect to run in, had excellent filtration, and fit every face. This is not meant to sound pessimistic but rather to acknowledge that even the best reusable masks will feel uncomfortable under different circumstances for different people.
Another deciding factor when it comes to finding a good mask? Fit. “I think people are super obsessed with the material question,” Dr. Fortune says, “The most important thing you can do rather than obsessing about whether the barrier function of this mask is ever-so-slightly different than the barrier function of that mask is find a mask that fits you and fits your face as best you possibly can.” If you can feel gaps around your nose, ears, cheeks, or chin, the mask is not as effective as it could be. We evaluated the fit of the masks in our lineup by having testers with various face shapes, face sizes, and features (such as a beard or glasses) wear the masks and determining how securely each mask fit each person.
First up in fit: putting the masks on. The masks attached to our heads in a variety of ways, and we liked some more than others. Fastening styles included loops that hooked behind our ears, sets of two or four strings that we tied behind our heads, bands, or some combination thereof. The masks with ear loops were the easiest to put on. However, testers with smaller faces often preferred the masks that tied behind their heads, because they allowed for a more tailored, tighter fit. And while the tie-on masks did take longer to put on than the ear-loop masks, testers with smaller faces valued a secure fit over saving the few seconds it took to adjust the ties. Of the masks with ties, we preferred those with ribbon or fabric ties to the one model with nylon cords, which were slippery and thus harder to tie.
Once attached, the shape of each mask also affected how well it fit. We preferred masks with a hump-shaped nose piece that raised them up off our mouths. They were easier to breathe in, fit more securely under our chins, and allowed for minimal gaps. Rectangular masks left too many gaps around the sides of our noses especially, while pleated masks, which are designed to fit different nose shapes and chin lengths, didn’t allow for a tight enough fit, especially around our noses. We also tested one face gaiter (see "Neck Gaiters: Is It Safe to Wear One as a Mask?"), but it did not fit small faces well and tended to fall down too easily.
Lastly, the masks that fit best were adjustable. Many of the masks in our lineup were available only in one size, and unless the masks had features such as adjustable loops or metal nose pieces that molded to the face, they did not fit everyone and often skewed bigger, working best for larger faces. We preferred masks with adjustable nose wires and adjustable ear loops, as they allowed wearers to tailor the fit of the masks to their faces. If the ear loops didn’t have an adjustable component or were made from elastic, we had success knotting them to get the mask to fit more snugly.
In the end, each of our testers preferred different masks—and each mask fit everyone a bit differently, no matter how adjustable they were. However, we can name an all-around best mask, one that ticked the boxes for safety, fit, breathability, and ease of use for the highest percentage of testers.
The Mandala Antimicrobial + Fluid Resistant Face Mask fit all our testers nicely, and its double-layered construction passed our filtration tests. Its hump-shaped nose piece and adjustable nose wire and ear loops allowed us to create a more customized, well-tailored fit, and it had an added filter pocket (see “Should You Wear a Filter with a Mask?”). Although it was too thick to comfortably run in, it was perfectly fine for walking around. While this mask’s “antimicrobial” properties have not been evaluated by the U.S. Food and Drug Administration, we did like that this mask’s outer layer was waterproof. A study by researchers at Northeastern University reported that using a waterproof cloth material to make a face mask could increase its effectiveness, acting as a barrier to repel respiratory droplets from entering through the mask. For a mask that is protective, comfortable, easy to put on, and fits most face shapes, we think this is an excellent option. And while this is our favorite all-around mask, we’ve also identified options for running, larger faces, and smaller faces. Since new masks are being introduced each day, we will continue to test new entries and update this story accordingly.