Face masks are an essential tool for slowing the spread of COVID-19. They work by blocking respiratory droplets that are expelled when people talk, cough, or sneeze. However, face masks with exhalation valves have been controversial, with some people arguing that they provide less protection than other types of masks.
The new videos provide clear evidence that face masks with exhalation valves do not effectively block the spread of respiratory droplets. The videos show that when people wearing these masks talk or cough, a significant amount of air and droplets escape from the sides of the mask. These droplets can travel several feet, potentially infecting people who are standing nearby.
In contrast, face masks without exhalation valves effectively block the spread of respiratory droplets. The videos show that when people wearing these masks talk or cough, very few droplets escape from the sides of the mask.
The researchers conclude that face masks with exhalation valves are not an effective way to slow the spread of COVID-19. They recommend that people wear face masks without exhalation valves to protect themselves and others from infection.
The World Health Organization (WHO) also recommends against using face masks with exhalation valves. The WHO states that these valves "can allow respiratory droplets to escape, potentially exposing others to infection."
