Course Information
Air is composed of 78% nitrogen, 21% oxygen and 1% other gases by volume. As altitude increases, the air pressure decreases, and as a result, the amount of oxygen available to support life functions decreases. At 33.000 ft, the amount of oxygen is almost a quarter less than at sea level. Aircraft cruising at altitudes above 25.000 ft have pressurization systems which provide a cabin altitude that contains sufficient oxygen for passenger and flight crew requirements and those aircraft normally do not need an oxygen supply. However, as a precaution, pressurized aircraft are fitted with built-in oxygen system to provide oxygen in the event of failure of the pressurization system and in the event of smoke or toxic fumes in the cockpit. With some of the smaller and medium size aircraft without cabin pressurization, oxygen equipment may be installed for use by passengers and crew when the aircraft is flown at high altitudes. Courses are constantly monitored and updated when major changes in authority documentation is released.
