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What is the average amount of cosmic radiation that flight crew members receive per year?
  • A
    the same as the radiation received during a chest X-ray.
  • B
    equal to the amount of background radiation.
  • C
    half the amount of background radiation.
  • D
    double the amount of background radiation.

Background radiation is the natural radiation that is always present in the environment. It includes cosmic radiation which comes from the sun and stars, terrestrial radiation which comes from the Earth, and civilisation radiation which results from medically applied radiation, household radiation, etc. This adds up to about 3.9 to 4.0 mSv per year in Europe.

As stated above, everyone, everywhere, is exposed to cosmic radiation. We are protected from cosmic radiation by Earth’s magnetic field and atmosphere. However, at higher altitudes in an airplane and particularly when closer to the North and South poles, the protection is less. During a commercial flight, cosmic radiation is several times higher than on the ground. According to studies, 1 h of flight time at cruise altitude cause an additional amount of 0.01 mSv of cosmic radiation, which means that the annual exposure of flight crew members adds up to about the same amount of background radiation.

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  • Austro Control
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  • United Kingdom