Facial hair and home oxygen therapy can prove a dangerously combustible combination, according to a Mayo Clinic report published in the peer-reviewed medical journal Mayo Clinic Proceedings. To reach that conclusion, researchers reviewed home oxygen therapy-related burn cases and experimented with a mustachioed mannequin, a facial hair-free mannequin, nasal oxygen tubes and sparks. They found that facial hair raises the risk of home oxygen therapy-related burns, and encourage health care providers to counsel patients about the risk.