The next time you hear an “achoo!” nearby, shield yourself.
A new study shows people blow out gas clouds when they sneeze or cough – and these clouds propel germs further than previously thought.
Scientists at MIT studied how coughs and sneezes move in slow motion using high-speed imaging, in addition to mathematical modeling techniques and simulations. They found that coughs and sneezes have two phases: A quick, jet-like propulsion of droplets, and then a “puff” in which the droplets are suspended in a gas cloud.
When the researchers analyzed the trajectory of the expelled particles, they found that relatively large droplets in the clouds – measuring 100 micrometers in diameter – moved five times further than previous studies had shown. The smaller ones, 10 micrometers across, traveled 200 times farther.
So stop the spread of disease by covering your coughs and sneezes.