April 22: MIT Medical answers your COVID-19 questions. Got a question about COVID-19? Send it to us at email@example.com, and we’ll do our best to provide an answer.
I’m wondering how wind might affect the six-foot social-distancing recommendation when I am outdoors? In particular, if I’m directly downwind of someone, should that distance increase?
We’re going to say, “probably not.”
But that answer comes with a few caveats. The first is that that the six-foot recommendation is not carved in stone. Rather, it has to do with the maximum distance that large respiratory droplets from a sneeze or cough are thought to travel, based on research done in the middle of the last century. However, more recent research shows that smaller droplets from coughs or sneezes may travel much farther than six feet. And wind could cause respiratory droplets of any size to travel farther still.
On the other hand, it’s not clear how this newer research applies to COVID-19 or if viral particles that have traveled a great distance would still be stable and concentrated enough to be infectious. A recent study showed that COVID-19 viral particles disperse, or break apart, relatively quickly in the air under normal conditions. Wind would make these particles diffuse even faster.
And, of course, though masks don’t negate the need for social distancing, they do keep those large respiratory droplets from traveling very far in the first place. Your mask protects other people, and their masks help to protect you.
But as far as the question of wind and social distancing, in all likelihood, it’s pretty much a wash. Although viral particles can be carried farther on a windy day, the wind would also offset that potential danger by dissipating those particles to the point where they’d pose very little risk. So, unless you are downwind of someone who is actively coughing in your direction, you’re probably safe maintaining a six-foot distance. And, meteorological conditions aside, if you’re anywhere in the vicinity of someone who is actively coughing and not covering that cough in any way, you should immediately put as much distance between yourself and that individual as possible.