Miners use them to self-rescue when it is oxygen-poor or toxic gas threats their life in coal mine. It can be also applied by the first aiders or workers from other enterprises or public institutions who works under the condition of oxygen deficit or toxic gas. Model ZYX30 Protect time â?¥30min Capacity of oxygen bottle 0.3L Oxygen storage capacity 56L Inspiratory oxygen concentration 25% Inhaled carbon dioxide concentration 2% Quantitative supply of oxygen 1.2L/min Manual supply of oxygen supply 60L/min Cylinder filling pressure 20Mpa Period of validity 3-5 years Outline dimensions 210*167*80mm