Facts About Radiation from Air Travel

What to know

Travel by air has become increasingly common, both for business and leisure travel. We are exposed to low levels of radiation when we fly. This amount of radiation is less than the amount of radiation we receive from one chest x-ray.

Airplane wing

Frequently asked questions

Radiation from air travel comes from cosmic radiation, or radiation from space. Cosmic radiation is produced by the stars, including our own sun. You would be exposed to about 0.035 mSv (3.5 mrem) of cosmic radiation if you were to fly within the United States from the east coast to the west coast.

The amount (dose) of radiation you get from air travel is low, but the dose depends on a few factors.

These levels of radiation are small and unlikely to affect human health.

1. Duration of the flight

The longer you are on a flight, the more radiation you receive.

2. Altitude

The higher you are in altitude, the higher the dose of radiation. This is a result of less shielding of cosmic radiation by the atmosphere at higher altitudes.

3. Latitude

The farther north or south you are from the Equator, the more radiation you will receive. This is a result of the Earth's magnetic field deflecting some of the cosmic radiation away from the equator and toward the North and South poles.

Whether you fly or not, a person's average dose from cosmic radiation is 0.33 mSv (33 mrem) or 11% of our yearly exposure to all natural sources of radiation.

Average Annual Dose for Natural Sources of Radiation

Source of Natural Radiation

Average Annual Dose

Percent of Average Annual Dose

Internal (by Inhalation)

2.28 mSv (228 mrem)


External (from Cosmic Exposure)

0.33 mSv (33 mrem)


Internal (by Ingestion)

0.29 mSv (29 mrem)


External (from Terrestrial Exposure)

0.21 mSv (21 mrem)


Average Annual Dose for Natural Sources of Radiation

Reference: National Council on Radiation Protection and Measurements. NCRP Report No. 160, Ionizing Radiation Exposure of the Population of the United States. https://ncrponline.org/publications/reports/ncrp-report-160

Air travel exposes travelers to low levels of radiation.

Radiation from air travel is a result of naturally-occurring radiation from space we are exposed to every day.

Watch this video to learn more about radiation exposure from air travel.