Oxygen and Cabin Pressure - Travel & Health Tips

During a flight, the air within the cabin is pressurized. However, it is always lower than the air pressure at sea level. Take this example-for an aircraft that cruises at an altitude of 36 000-40 000 feet (11 000- 12 200 meters), the cabin air pressure is equivalent to that at 6000-8000 feet (1800-2400 meters) above sea level. Under such conditions of low pressure, the blood takes up lesser oxygen (hypoxia) and gases within the body expand. While this poses no problems for healthy travelers, those with heart or lung disease and anemic patients may need additional oxygen supply.