Work out radiation exposure from flight instantly with clear inputs, formula shown and shareable results.
Cosmic radiation intensity roughly doubles every 2000 m of altitude and is higher near the poles because the geomagnetic field deflects less there. At 11 km on a mid-latitude route the rate is about 5 uSv/h, so an eight hour flight delivers 40 uSv - two chest X-rays, or 1.7% of the 2400 uSv annual natural background.
Dose rate scaling
roughly doubles per 2000 m of altitude
Total dose
dose = rate x flight hours x route factor
Aircrew are classified as occupationally exposed in many countries, typically accumulating 2-5 mSv a year - comparable to natural background but monitored.
Because Earth's magnetic field funnels charged particles towards the poles rather than deflecting them, so shielding is weakest there.