Lip reading is something we do every day whether we realize it or not. Using facial expressions, watching speech movements, and simply watching the talkers face all allow us to enhance the speech we hear. Working in a health office and previously in retail allowed me to relate this to the current COVID pandemic. I distinctly remember people say "sorry I can't hear you, I'm wearing a mask", and at the time, I'd just chuckled and repeated what I said. But after going in deeper to what actually goes into speech perception, I realized that having the majority of our face covered really affects speech communication.
I found an article in The Journal of the Acoustical Society of America which compares different types of face masks (N95, surgical, cloth etc.) and their effect speech perception. This study focused in on acoustic output and speech perception The link is down below: