Safe Oxygen Range
Safe Oxygen Range : A minimum oxygen content in air of 19.5 percent by volume under normal atmospheric pressure (equivalent to a partial pressure of oxygen (pO2) of 19.8 kPa (148 mm Hg)), and a maximum oxgygen content in air of 23.5 percent by volume under normal atmospheric pressure (equivalent to a partial pressure of oxygen (pO2) of 23.9 kPa (179 mm Hg)