Minimally invasive arthroscopic procedure to remove articular cartilage in the knee. Articular cartilage is a firm rubbery tissue that covers the ends of bones. It provides a smooth gliding surface for joints and acts as a cushion between bones. Cartilage can break down due to overuse or injury.
While normal atmosphere contains between 20.8 and 21 percent oxygen, OSHA defines as oxygen deficient any atmosphere that contains less than 19.5 percent oxygen, and as oxygen enriched, any atmosphere that contains more than 22 percent.
Oxygen is naturally present at a concentration of 21% in the. air we breathe. The health effects described in this Fact Sheet. may occur when breathing pure Oxygen or concentrations. greater than 40%. * OSHA defines an Oxygen-deficient atmosphere as having. less than 19.5% Oxygen by volume.