A doctor based in Dublin, Ireland, has debunked the idea that a face mask lowers oxygen levels. In fact, he’s shown that even wearing several has no effect.
This July 14 video shows Maitiu O Tuathail putting six masks on his face while recording his blood oxygen saturation levels. As he puts on mask after mask, the meter shows a steady, and healthy, 98-99 percent.
O Tuathail shared the video on Twitter to debunk the misconception that face masks negatively affect oxygen levels. He said he was being asked this regularly by patients, who were citing misinformation they had found on social media. Credit: Maitiu O Tuathail via Storyful