Listen to the podcast below, where we answer the question: Do valves on respirators impact their effectiveness? (Here’s the LinkedIn post that started this conversation, making it a great topic for a podcast.)
The purpose of a respirator’s exhalation valve is to reduce the breathing resistance during exhale; it does not impact a respirator’s ability to provide respiratory protection. The valve is designed to open during exhalation to allow exhaled air to exit the respirator and then close tightly during inhalation, so inhaled air is not permitted to enter the respirator through the valve.
While a valve does not change a respirator’s ability to help reduce a wearer’s exposure to bioaerosols, a person who is exhibiting symptoms of illness should not wear a valved respirator, because exhaled particles may leave the respirator via the valve and enter the surrounding environment, potentially exposing other people.
Also, you can check out the CDC FAQ on this topic here.