Hypobaric Hypoxia in Aircrew

Hypobaric hypoxia is caused by insufficient oxygen in the crew due to low atmospheric pressure. It causes hypoxemia and the symptoms of hypobaric hypoxia progressively develop, making the crew unable to perform executive functions. Aircraft accidents due to the development of hypobaric hypoxia in the crew have caused hundreds of casualties in the modern era of aviation, involving different aircraft and in other countries. To prevent such accidents, the aircrews perform simulated hypobaric chamber exercises periodically, in this way, it is possible to introduce the symptoms of hypobaric hypoxia to them in a safe and controlled atmosphere. Consequently, this allows them to remember hypoxia symptoms during an eventual aviation incident. The interval between hypobaric chamber exercises varies between countries. Although they are not mandatory, it is suggested that an interval of between three and six years between hypoxia exercises is appropriate to maintain flight safety concerning hypoxia symptoms. However, it is important to be aware that there is intra- and inter-personal variability in hypobaric hypoxia symptoms.