The widespread availability, and use, of inexpensive pulse oximeters opened the eyes of many in the aviation community to what the aeromedical folks have been telling us for years: The FARs on oxygen give a false sense of security to pilots. Pilots who are in full compliance with the regs are often oxygen-deprived to a level that adversely affects their ability to operate the airplane. The good news is that there are a number of reasonably priced, high-quality portable oxygen systems to help protect yourself against hypoxia and make your flights safer and more comfortable.
Breathing 101
Oxygen makes up some 21 percent of air. Every pilot knows that as you gain altitude, the air molecules get farther apart so it’s increasingly difficult to convince oxygen to pass through the human lung and join with hemoglobin to oxygenate the bloodstream. As the blood’s oxygen saturation level drops, it leads to hypoxia, an evil, wicked, mean and nasty condition. It causes, among other things, deterioration of mental and physical functions as we’ll as loss of vision. All the while, it neatly obstructs the pilot’s ability to recognize its onset because its most powerful symptom is euphoria—”Everything is great!” For a frightening example of the effects of hypoxia, here’s a recording of a hypoxic Learjet crew talking.