Your questions, masked and answered
"Are there instructions for making useful masks at home? Not just generalized, such as two layers of T-shirt and rubber bands, but detailed?" – Teddy Knight in Berkeley, Calif.
Are there ever! We'll suggest some tutorials below, but first we need to address whether homemade masks are a good idea at all.
There is no simple answer to this. Current government guidelines say healthy people don't need to cover their faces in public; some officials even warn against it. There hasn't been a lot of research on whether homemade masks work against viruses. Masks also have the potential do more harm than good if used improperly: they can get dirty and collect bacteria, encourage face touching and give people a false sense of security.
But the federal government is considering changing course and recommending more widespread mask usage. There is at least some limited evidence that masks can slow disease spread, and several medical experts have recently endorsed masks for everyone, including in our op-ed page.
If you decide to make a mask, here's what you should know from our recent guide to the subject:
Don't rely on a mask to protect you from the virus. Homemade masks were widely used during the 1918 pandemic, and people still died by the millions. There are some clever DIY designs on the Internet, but so far none has been proven effective. So mask or no mask, keep doing all the usual hand-washing and social-distancing.
Choose a mask design that fits snugly. It won't protect anyone if contaminated particles and air are leaking out the edges. The mask should reach above the bridge of your nose and under your chin, and strap tightly around your ears.
Choose good material. Too porous, and it won't filter anything. Not porous enough, you'll have trouble breathing. Several medical centers recommend using tightly woven, high-quality cotton or cotton blends. Peter Tsai, a scientist who invented the electrostatic charging technology used in medical-grade N95 masks, suggests using blue shop towels. In general, you'll want to layer the material for more protection.
If you can sew, several hospitals have released tutorials online. Providence St. Joseph Health has an 11-minute video showing how to make a cotton mask with half a yard of fabric and some thread. Other health systems have released their own instructions, which you can find in our story.
Amateur videos show how to make masks with basic household supplies. This one, for example, uses shop towels, rubber bands, paper clips, tape and a stapler. YouTube abounds with more, and there's a Facebook group for people experimenting with other designs. Be especially cautious when following amateur advice.
Never wear a dirty mask. One of the worries about homemade masks is their potential to trap moisture, bacteria or virus particles. You should wash yours with soap daily and hang it to dry, ideally it in the sun. Never share it with others, and consider making multiple masks so you can rotate them.
Be careful taking it on and off, or adjusting it. Another issue with homemade masks is they can encourage people to touch their faces, which is one way the virus spreads. An assistant professor of exposure and assessment science at Harvard University offers advice on how to handle yours safely here.