You may have heard that N95 and surgical masks are your best option for stopping COVID-19. "There are two face masks presently circulating: the N95 mask and the surgical mask," Quigley says. You'll likely recognize the N95 mask from pictures of health care workers. The surgical or medical mask is the disposable paper kind used by doctors. Even if you can access an N95 or surgical mask, though, they should be reserved for people who really need them on the front lines.

"N95s are most appropriate for health care providers and first responders as they're impervious to the virus," Quigley says. "This mask is in short supply and should be only acquired by those at risk." The same applies to surgical masks.

This is why the CDC initially told people who weren't working in hospitals that they didn't need to wear masks, Burchett says. "If there's a shortage of masks, health care workers should get them first."

Instead, make your own out of fabric you already have at home. The CDC has a handy tutorial, and there are other guides that combine materials like old T-shirts, bandanas, coffee filters, and old hair ties for DIY masks. It's not yet known exactly how effective face masks are in preventing coronavirus spread, but researchers told The Atlantic that mathematical models showed 80% of the population wearing masks that were at least 60% effective could slow down viral spread significantly.

Surgical face masks and homemade cloth face masks won't fully protect you from COVID-19. "They cannot filter out the small viral particles found in exhaled respiratory droplets that can potentially get you sick," Quigley says.

Their major use, he says, is to stop people who are asymptomatic or have recently tested positive from COVID-19 from spreading germs. "A face mask will prevent your respiratory droplets, to some extent, from infecting someone else, whether in your household or in public." It's not so much to protect you from others; it's to protect others from you. Scientists now know that many people with COVID-19 may not have any symptoms at all, which is why this is so necessary.

Face masks can be helpful, but their effectiveness depends on their type. According to studies, N95 masks are most effective at preventing the spread of both large and small droplets, followed by surgical masks, hybrid masks (combining high thread count cotton with another fabric like silk), and two-layer cotton masks. All are very good at preventing the spread of droplets, but none are 100% effective. There's still a risk of spreading the virus in a closed environment — say, a hermetically sealed White House car.

If you're using a disposable surgical face mask, you can't keep using it. "Surgical face masks, even if kept clean, are not reusable," Quigley says. You should also wash your hands once you dispose of them.

Cloth face masks can be reused but under strict guidelines. "Once the masks are used outside the home, they need to be carefully removed without touching the outside layer and washed immediately in hot/warm soap and water," Dr. Teresa Bartlett, M.D., senior medical officer at Sedgwick, a claims management service, tells Bustle. They should also be washed immediately before being used.

Covering your face don't mean you shouldn't keep your distance. "If you’re in any kind of community setting, the CDC still recommends that you stay at least six feet away from other people, otherwise known as social distancing, even if you’re wearing a face mask," Quigley says. "This is in addition to maintaining good hygiene practices such as frequent hand washing and other everyday preventive actions."

Masks don't mean you can be lax about hand sanitizer, the 20-second hand-washing rule, or any of the other tips we've learned about stopping COVID-19 transmission. It also doesn't mean that you're good to hang out at the park with your besties as long as you're wearing one; you still need to minimize your contact with other people to what's absolutely essential.

The main purpose of wearing a mask, according to the CDC, is to stop you spreading germs in places like the grocery store or bank. However, if you've tested positive for COVID-19, or any person in your household is vulnerable to getting sick, it may be a good idea to wear them inside. "They are a great way to protect others within the home, as the one who has tested positive for COVID-19 should wear the mask indoors," Bartlett says.

DIY face masks are preferable to surgical or N95 masks if you're not a first responder or health care worker, but it's important to make and wear them properly. "Fabric masks should have pleats and can be multilayer to prevent the virus from getting out or penetrating in," Barlett says.

Face masks made at home are most effective, Quigley says, when they fit your face properly. "Be sure that the cloth face masks you’ve created or purchased are wide enough to cover your nose and chin and are snug enough to not create gaps. This tight fit will help keep particles from traveling through the air escaping the gaps," he says. And, he adds, masks do need to cover your chin as well as your mouth and nose.

Even though the CDC recommends using them in a pinch, bandanas and scarves don't offer the recommended pleats, multi-layer protection, or snug fit around your face, so it's worth making your own mask or buying one. In fact, a recent study found that some face coverings people use as masks — like neck gaiters — can spread even more viral particles than not wearing a mask at all.

There's some evidence that the more dense layers you use, the more effective a mask may be — so reinforcing a DIY mask with pantyhose, for instance, may help its effectiveness.

Masks may well be the key to allowing the economy to reopen and letting people out of the house, Burchett says, since there won't be a coronavirus vaccine or treatment for a while. "They are part of the solution," he says. Countries that adopted strict face mask use early, like the Czech Republic and Germany, have claimed that those policies helped keep casualty numbers low. The CDC's new face mask policies are aimed at lowering the transmission rates in U.S. communities, and it will only be clear if it works after months of testing.

"Now is probably time to find a style you like and can tolerate," says Burchett, "because I imagine them in everybody's foreseeable immediate future."

Wearing a mask might be slightly less comfortable than going bare-faced, but it definitely protects against spreading coronavirus, and it definitely doesn't deplete your oxygen levels or cause CO2 retention, as some have claimed. Cloth and surgical masks aren't tight enough to restrict oxygen, and even fitted N95 masks allow oxygen and CO2 to flow, according to Stanford University. “Carbon dioxide molecules freely diffuse through the masks, allowing normal gas exchange while breathing," Dr. Robert Glatter, M.D., an emergency physician at Lenox Hill Hospital, told Healthline. You can breathe easy knowing mask-wearing won't affect healthy adults' oxygen levels, but will reduce the risk of catching coronavirus — or infecting others with it.