I am not suggesting this simply because I am very sick of wearing a mask at all times outside my home. When it comes to coronavirus spread, evidence shows that being outdoors is very, very safe. A paper published in Indoor Air looked at 1,245 cases in China and found just one instance of outdoor transmission, which involved people having a conversation, which means they had to be close to one another for some period of time and face to face. According to data from the Health Protection Surveillance Centre, shared earlier this month with the Irish Times, of 232,164 cases in Ireland, just 262 were associated with “locations which are primarily associated with outdoor activities.” That is, about 0.1 percent. A meta-analysis published online in November in the Journal of Infectious Diseases suggests it’s possible the upper bound of cases potentially contracted outdoors is higher; it estimates that the total is less than 10 percent. When I called Nooshin Razani, an author on that report and an associate professor of epidemiology and biostatistics at the University of California, San Francisco, she emphasized that the real number of instances of outdoor transmission was “probably lower” than 10 percent, since the cases she and her team counted were sometimes murky: cases that occurred at construction sites, or summer camps where people were sharing bunks. That is, these scenarios likely involved some indoor time as well. They also tended to involve people who were spending time together over a period of days. “Most of the cases that happened outdoors had something about the circumstances you could point to and say, ‘That was a risk,’ ” says Razani. Just one case involved joggers—who were jogging together. Still, Razani said she couldn’t comment on whether it was OK to go maskless on a sidewalk where you’re able to mostly, but not perfectly, stay distanced from others. In an article in National Geographic by science writer Tara Haelle, other experts note that yes, we have data that the outdoors is very safe, and yet, if you can’t distance, even briefly, you might want to pull up your mask, partly out of respect, and also just to be safe. I have to say: I don’t agree! It’s true that nothing is 100 percent safe. But because little particles floating through the air are a main concern with COVID, the outdoors is very, very safe. Anything you exhale will just be diluted very quickly, especially if you’re moving around. Yes, the coronavirus can spread in other ways. As Razani said, “If you’re right next to someone and you spit on them outdoors, it’s not going to magically protect you from their spit.” But that comment illustrates that the risk of getting COVID while briefly coming within 6 feet of someone outside is so small that your exchange of fluids would almost have to be purposeful.