“It’s a common-sense precaution,” Lipsitch says, adding that it “should be at least partially protective.” He also notes that homemade masks also remind us not to touch our faces and are a visible reminder of the need for good hygiene.
Is a homemade mask better than a bandanna or scarf?
“The main point is to cover your nose and mouth and not touch whatever’s there,” says Murray, who has seen balaclava ski masks and even jockstraps used as masks. Whatever option you use can make sense as long as the material is thick but breathable, she adds. With that said, homemade masks seem to have at least a few potential advantages over bandannas and scarves.
The general rule, according to the experts, is that the tighter the weave of the fabric, the better the protection. Making your own mask allows you to choose whichever material is available to you with the tightest possible weave. Which fabric might that be, you ask? The 2013 Disaster Medicine and Public Health Preparedness study offers some clues. First, some context: This study was looking specifically at whether homemade masks could offer some protection in the event of another influenza pandemic. Influenza viruses are about 60 to 100 nanometers in diameter, just a bit smaller than coronaviruses, which usually range from 120 to 160 nanometers in diameter. It stands to reason that materials that can block influenza viruses should be able to block larger coronaviruses as well. To that end, the study found that vacuum cleaner bags seemed to offer the best protection against influenza viruses after surgical masks, but that tea towels, cotton T-shirts, and cotton pillowcases did a fair job of blocking particles too. Other testing suggests that double-layer masks of heavyweight quilter’s cotton with a thread count of at least 180 are a good filter, as well as thick batik fabric.
When it comes to bandannas and scarves, it depends on what they’re made of. But preliminary lab experiments by engineers at Missouri University of Science & Technology suggested scarves and bandannas weren’t very effective at filtering out small particles. (This testing found furnace filters to be the best material for this purpose.) Bandannas and scarves also may not tie as firmly as a homemade mask, so you’ll be tempted to readjust them and touch your face, Murray adds. Still, “it’s likely better than nothing,” says Lipsitch.
This is what to remember when making your homemade mask.
The CDC has online tutorials for making sewn and no-sew homemade face masks using materials like T-shirts, hair ties, bandannas, and coffee filters. The New York Times and CNN also offer helpful mask-making tutorials.
Whichever instructions you follow when making your mask, be sure to incorporate these tips:
- Test the straps. Your mask should fit snugly against the sides of the face. You might find you prefer loops behind your ears or double ties behind your head. Either way, just make sure the elastic is the right length so it’s snug but comfortable.
- Try it at home first. Give your finished mask a test run for at least half an hour to see how much you’re tempted to fidget with it. “If you’re going to touch your face more than when you’re not wearing a [mask], it’s not a good idea,” says Murray.
- Don’t be afraid to experiment. Test out a few designs to find the most comfortable one, suggests Lipsitch, whose 13-year-old daughter, Gabriella, has actually sewn more than 30 masks so far for friends and family. “Give yourself time to experiment and find what works for you,” says Murray.
Here’s how to wear your homemade mask safely.
Even though the CDC specifically recommends wearing a face mask in crowded spaces like grocery stores, you may decide to wear one every time you’re outside if you live in a densely populated city where it’s hard to maintain a six-foot distance from others. (In fact, large cities like Nice, France, have begun requiring masks in public.) If you’re going for a walk or run outside, air is circulating and there’s less infection risk than if you’re standing with others in an enclosed space. “The quicker you pass that person and go on your way, the less likely you are to be exposed,” Gabriela Andujar Vazquez, M.D., an infectious disease physician and associate hospital epidemiologist at Tufts Medical Center, tells SELF. Still, it’s not a bad idea to wear a mask if you’re not sure you can maintain your distance.