If you’re fully vaccinated, you (mostly) don’t need to wear a mask outdoors

New guidance from the CDC says that unless you're in a crowd, vaccinated people don't need to wear masks outside.

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Unless you’re going to a crowded venue, getting fully vaccinated now officially means you can go maskless outdoors. That’s according to updated guidance from the Centers for Disease Control released on Tuesday.

Fully vaccinated, of course, means not just that you’ve had both shots of either the Moderna or Pfizer COVID vaccines (or one shot of the Johnson & Johnson option), but that you’ve waited two weeks after the final dose. It takes that long for your immune system to fully build up a defense. But once at that point, gathering outdoors without masks is an officially sanctioned option. The CDC still recommends that you don a mask for any indoor activities, but once vaccinated even those activities are much lower risk.

The new guidance reflects something we’ve known about SARS-CoV-2 for a while now: The risk of transmission outdoors is much lower than the risk inside. Ventilation is key to preventing the spread of the aerosol droplets that carry the virus, so open-air spaces have always been the safest option. The World Health Organization’s advice since December has been that no mask is required as long as people are able to maintain about three feet of distance between them, even without a vaccine. So the low outdoor risk, combined with the protection of a vaccine, makes socializing outdoors very low risk.

[Read more: How long will we keep wearing masks?]

Visiting indoors with unvaccinated people is also considered fairly safe, though if that person is at high risk for severe COVID-19—like if they’re immunocompromised—it’s still advised to wear a well-fitting mask. And if you’re gathering multiple households together, mask-wearing is still advised indoors. But if you’ve been wearing a mask to go running or to gather outside with your friends, you can feel free to leave it off once you’ve gotten your shots.

Public health experts are noting that incentives like this could be important motivators for those on the fence about getting vaccinated. The more people that get vaccinated, the more of these activities we’ll be able to do maskless.

A less-cited point from the new guidance is that every single activity on the CDC’s chart is marked as safe if you’re vaccinated, including going to an indoor movie theater, singing in an indoor chorus, and participating in exercise classes inside. Though the recommendation is still to wear a mask, this is the first official acknowledgement that virtually all activities are safe once you’re vaccinated. It will most likely require case counts coming down farther, combined with a more vaccinated population, for mask mandates to be lifted for indoor settings. But this is a crucial step towards getting back to normal.

In the meantime, consider getting vaccinated as your ticket to enjoying most part of your life again, albeit with a mask for now.

Sara Chodosh

Sara Chodoshis an associate editor at PopSci where she writes about everything from vaccine hesitancy to extreme animal sex. She got her master's degree in science journalism at NYU's Science Health and Environmental Reporting Program, and is getting a second master's in data visualization from the University of Girona. Contact the author here.