I #WearAMask for my entire shift in the ER. There are ZERO harmful effects of wearing a mask, and you could save someone’s life. I went in before my shift to perform this demonstration of Oxygen levels while wearing a mask. 💥SPOILER ALERT💥 They’re normal. pic.twitter.com/Zh8tRBFdqT

— Dr. Rob Davidson MD, MPH (@DrRobDavidson) June 29, 2020