Air travel for the chronically ill and the elderly.

The cabin altitude during airline flights is usually 1,500 m (5,000 ft). Medically important factors include the decreased bioavailability of oxygen, the dryness of the air and the properties of gases within the body as stated in Boyle's law. Passengers who are physically compromised by chronic disease, advanced age or mobility impairment can usually have their special requirements met through the cooperation of the family physician and the airline. Special diets, supplemental oxygen, locomotive aids and communication services are provided on advanced request.