Passengers on planes flying near or through lightning storms could be exposed to harmful levels of radiation. Lightning discharges, or a related phenomena known as terrestrial gamma-ray flashes, can jolt airline passengers with a level of radiation equivalent to 400 chest X-rays.
A study was conducted to estimate radiation levels based on satellite and ground observations of X-rays and gamma rays. Terrestrial gamma-ray flashes are mysterious phenomena that are believed to originate at the same flying altitudes as airliners. Scientists believe they are produced in the electric fields above the thunderstorms.
Using computer models to estimate the levels of radiation produced within or near thunderclouds during a lightning storm, researchers concluded that the amount of radiation within immediate proximity to these lightning events could be high enough to be considered a "biologically significant level."