Most of the radiation at high altitudes comes from exploding stars in our own galaxy. It is called cosmic radiation and consists mainly of energetic particles (protons, alpha particles and helium nuclei). Cosmic radiation is absorbed by the atmosphere so that only a small amount reaches us on the ground.
Radiation levels at the heights where aircraft cruise are about twenty times higher than at sea level. As a result anyone in the aircraft is exposed to a dose of radiation. The more often a person flies the larger the amount will be. A typical airline pilot receives a larger annual radiation dose than someone working in the nuclear industry.
There is evidence that aircrew can experience damage to their health. They run a risk while their employers and others benefit; the airlines and the tourist industry make profits and passengers fly for convenience or pleasure.
How can radiation damage your health?
Where things went wrong: The Radium Girls
Why do airline pilots and aircrew do this work if they know it is dangerous?
How can their exposure be kept as low as possible?
What else can be done to prevent them becoming seriously ill?
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