A new study highlights the importance of wearing masks.
The study, published online for the scientific journal Physics of Fluids, contains images that show a manikin modeling different masks. Researchers used a fog or smoke machine to simulate "respiratory jets" or droplets from coughs and sneezes.
The pictures visualize how far those droplets can travel with a mask or without one, and how much air bleeds or leaks from the sides or top of a mask that doesn't fit properly.
Dr. Mark Cameron, an infectious disease researcher and professor at Case Western Reserve University's School of Medicine, said the study shows that "mask usage was far more effective than no mask at all."