When it comes to face masks, not all are equally effective, a new study finds.
Duke University researchers developed a way of testing various types of masks to see which did the best job of stopping droplets coming from people's mouths, preventing spread of the new coronavirus.
They relied on a makeshift apparatus consisting of a box, a laser, a lens and a cellphone camera.
"We confirmed that when people speak, small droplets get expelled, so disease can be spread by talking, without coughing or sneezing," said Martin Fischer, a chemist and physicist at the Durham, N.C., campus. "We could also see that some face coverings performed much better than others in blocking expelled particles."Click here to read the full story on WebMD. Read More