Health Desk- 12 August, 2020: Health experts have determined that face coverings are a vital tool in reducing the spread of coronavirus -- but little research has been done into how different kinds of masks compare.
A new study has ranked 14 types of commonly available mask, finding that medical masks offer significantly more protection against droplet spread than cotton alternatives -- while bandanas and balaclavas don't do much at all.
The findings have public policy implications, particularly in the United States where authorities have encouraged the public to use textile masks and leave the medical products to health care workers because they are in short supply.
Masks are important because some 30-40 percent of people who are infected may not show symptoms but still unwittingly spread the virus when they cough, sneeze or just talk.
A team of scientists at Duke University created an inexpensive setup: people stood in a dark room and spoke the words "Stay healthy, people" five times into the direction of an expanded laser beam, which was recorded with a cell phone camera. A computer algorithm was then used to calculate the number of droplets.