Jeremy Renner is sharing the oxygen treatment he undergoes twice a day.

On Sunday, the 52-year-old actor posted a selfie on his Instagram Story while receiving hyperbaric oxygen therapy as he continues to recover from his Jan. 1 snowplow accident.

“Hyperbaric chamber, 2 atmosphere pressure, high oxygen, 2x daily,” the Hawkeye star wrote over the photo.

Hyperbaric oxygen chambers can be used to treat several medical conditions, including crushing injuries like Renner’s.

Human body tissue needs oxygen to function, and the air people breathe is 21% oxygen. Hyperbaric oxygen chambers create an environment where patients can breathe 100% oxygen, according to the FDA. Once a patient is in the chamber, the air pressure in the unit is raised to a level about 2 or 3 times higher than normal, which helps the lungs collect more oxygen. The oxygen goes through the bloodstream and essentially overflows into tissues, which can speed up the healing process.

In addition to injuries, HBOT can be used to treat other medical conditions like burns, severe anemia, carbon monoxide poisoning, radiation injuries, traumatic brain injuries, and more. It is also commonly used for treating scuba and deep-sea divers affected by the rapid pressure change.

At the beginning of the year, Renner suffered more than 30 broken bones and required multiple surgeries after he was run over by a 7-ton snowplow. He’s kept fans updated on his ongoing recovery in the months following his hospitalization.

Last month, the Avengers actor — who has used a cane publicly since the accident — walked freely, with a bit of support from his friend and fellow actor Casey Affleck, while attending Kate Beckinsale‘s birthday party.

Back in his first interview after the accident, the Oscar nominee told ABC News’ Diane Sawyer that he has “shift[ed] the narrative of being victimized or making a mistake or anything else.” Renner said, “I refuse to be haunted by that memory that way.”

Cited by: People