The Federal Aviation Administration (FAA) should strengthen how it tracks and explains cosmic radiation risks for pilots and flight attendants, according to a new National Academies report that says the FAA’s current approach is “inconsistent and insufficient” to manage aircrew exposure.
The report says in-flight cosmic radiation should be treated as an occupational hazard, with improved tracking, clearer crew education and practical steps to manage cumulative exposure over a career.
The report was requested by Congress under the FAA Reauthorization Act of 2024 and sponsored by the FAA.
Cosmic radiation is not new, and it is not a risk unique to aviation. But airline crews spend much of their working lives at altitudes where the atmosphere provides less shielding from high-energy particles from space.
Radiation levels vary by altitude, latitude, flight duration and solar activity. Long-haul and high-latitude flying can produce higher doses than shorter domestic flights at lower latitudes.
The issue is cumulative exposure over a career, not the risk from any single flight.
The National Academies said flight crews receive among the highest occupational radiation exposures of any worker group in the United States, but are not covered by the same kind of monitoring and worker-education practices used in some other radiation-exposed jobs.
The National Academies said the FAA should revise its approach to aircrew radiation exposure, improve how information is communicated and consider practical mitigation strategies.
Airliners cannot practically be shielded from cosmic radiation. Instead, researchers say airlines and regulators can model crew exposure by route, altitude, latitude and solar activity, then use that information to manage cumulative dose, especially for pregnant crewmembers.
NIOSH, the National Institute for Occupational Safety and Health, says ionizing radiation is known to cause cancer and reproductive problems. It also says aircrew appear more likely to develop skin cancer and breast cancer, although the causes are difficult to separate from other aviation-related factors, including circadian disruption and ultraviolet exposure.
Studies have not shown a broad, dramatic cancer surge among pilots. Some research has found increased risk for melanoma and other skin cancers, breast cancer among flight attendants, and possible reproductive risks. Researchers have also noted an association between pilot cosmic radiation exposure and nuclear cataracts, a type of cataract that forms in the center of the eye’s lens.
Researchers have not proved that cosmic radiation alone explains those findings.
Pilots are generally healthier than the broader population and receive regular medical evaluations, which can make long-term health studies harder to interpret. Most crews have also not worn radiation detection equipment throughout their careers, so exposure usually has to be estimated from flight history rather than directly measured.
The report does not say airline flying is acutely dangerous. It says the FAA has not done enough to track a known workplace risk or give crews clear information about it.