Common question
Are valve masks effective at preventing the spread of COVID-19?
Valve masks have a one-way valve allowing exhaled air to pass through a small round or square filter attached to the front. They only filter air breathed in, not breathed out. So it may protect the wearer from some pathogens in the air, but it does nothing to protect the people around you.
Why shouldn't material masks with exhalation valves be used during the COVID-19 pandemic?
• Do NOT wear cloth masks with exhalation valves or vents since they allow respiratory droplets containing the virus to escape.
