Stay 6 feet apart, we’re told. But how far can air carry the coronavirus?
The rule of thumb, or rather feet, has been to stand six feet apart in public. That’s supposed to be a safe distance if a person nearby is coughing or sneezing and is infected with the novel coronavirus, spreading droplets that may carry virus particles.
And scientists agree that six feet is a sensible and useful minimum distance, but, some say, farther away would be better.
Six feet has never been a magic number that guarantees complete protection. The Centers for Disease Control and Prevention, one of the organizations using that measure, bases its recommendation on the idea that most large droplets that people expel when they cough or sneeze will fall to the ground within six feet.
This 3-D Simulation Shows Why Social Distancing Is So Important
We visualized a cough to show how far respiratory droplets can spread. If you haven’t been keeping your distance to fight the coronavirus, this may persuade you.
But some scientists, having looked at studies of air flow and being concerned about smaller particles called aerosols, suggest that people consider a number of factors, including their own vulnerability and whether they are outdoors or in an enclosed room, when deciding whether six feet is enough distance.
“Everything is about probability,” said Dr. Harvey Fineberg, who is the head of the Standing Committee on Emerging Infectious Diseases and 21st Century Health Threats at the National Academies of Sciences, Engineering and Medicine. “Three feet is better than nothing. Six feet is better than three feet. At that point, the larger drops have pretty much fallen down.”
Reporting was contributed by Karen Weintraub, Knvul Sheikh, James Gorman and Kenneth Chang