"“I think it’s highly unlikely that you would pass out from a lack of oxygen with a cloth mask, which generally doesn’t fit tightly to your face. When you exhale or inhale, air can go around the mask as well through the pores in the material. This is why a cloth mask does not absolutely protect you from inhaling the virus, but by disturbing your exhalation flow it tends to protect those around you from aerosols in your breath.”"
"Kelli Randell, MD, an internist and medical advisor at Aeroflow Healthcare, tells Health that prolonged use of any face mask, including the N95 respirator, has not been shown to cause carbon dioxide toxicity in healthy people. “Because breathing is slightly harder with a mask, I do recommend that people who suffer from severe COPD or other lung diseases that make breathing difficult carefully consider the use of face masks,” says Dr. Randell. "