Masks—they’re not going anywhere. Currently, 34 states now mandate mask covering in public. Target even devoted a page of their recent Back to School circular to our new favorite accessory. Since we’re in this for the long-haul, you might want to make sure your mask material is the best choice for protection before you pick out your next mask pattern or accompanying chain.
Researchers at Duke University did the hard work for us by analyzing which mask were most effective in preventing the spread of the coronavirus. To conduct a study on the most commonly used types of face coverings, physicists had speakers wearing different coverings speak into a black box with a laser shining inside of it.
As each subject spoke regularly into the box, the team recorded how much light from the laser beam scattered from the respiratory droplets that came through the facial coverings. “We use a black box, a laser, and a camera," explained study author Martin Fischer to CNN. "The laser beam is expanded vertically to form a thin sheet of light, which we shine through slits on the left and right of the box."
Photo Credit: Emma Fischer, Duke University
Of the 14 masks included in the study, each mask was tested 10 times. As a result, the study found that many masks, like bandanas, gaiter mask commonly used by runners and knit masks, were completely useless. Not surprising, N95 medical grade masks, three-layer surgical masks and cotton masks proved to deliver the best protection.
Fleece mask turned out to be the worst kinds of masks because they broke down the droplets into such smaller pieces that it made it easier for particles to travel through the air. "We were extremely surprised to find that the number of particles measured with the fleece actually exceeded the number of particles measured without wearing any mask," said Fischer. "We want to emphasize that we really encourage people to wear masks, but we want them to wear masks that actually work."
