Exhalation valve for use in homemade fabric face masks. Comprised of three parts: a plastic base, an inner flexible disk, and a plastic cap.
Masks with exhalation valves. Masks with exhalation valves or vents are not recommended. This is because they allow infectious respiratory particles to spread outside the mask. These masks do not protect others from COVID-19 or limit the spread of the virus.
WHO does not advise using masks or respirators with exhalation valves. These masks are intended for industrial workers to prevent dust and particles from being breathed in as the valve closes on inhale. However, the valve opens on exhale, making it easier to breathe but also allowing any virus to pass through the valve opening.
