Pilots and flight attendants spend their careers working in a unique occupational environment. At cruising altitude, they are routinely exposed to elevated rates of naturally occurring cosmic ionizing radiation, an exposure that has long prompted questions about how it should be monitored, communicated, and studied for flight crew. 

A new congressionally mandated National Academies report is bringing renewed attention to those questions, recommending a more consistent approach to occupational radiation safety across the aviation industry. Assessing Radiation Exposure, Health Outcomes, and Mitigation Strategies for Flight Crewmembers outlines recommendations for developing radiation safety programs, improving education for flight crews, and starting a centralized system to track cumulative radiation exposure over a career. 

Pilot and flight attendant organizations have drawn attention to its recommendations as an important step toward addressing concerns raised by flight crews for years. 

A Routine Part of Flying for a Living 

Approximately 513,000 flight attendants, pilots, copilots, and flight engineers worked between 1999 and 2023. These flight crews were exposed to radiation on a regular basis. The radiation dose flight crews receive during any individual flight is generally low, but accumulate over time and varies based on altitude, latitude, flight duration, and solar activity. For example, long flights at high latitudes result in greater doses than shorter routes or those closer to the equator. 

Additionally, rare solar energetic particle events can temporarily increase exposure on affected flights. Although these events may contribute only a small portion of a flight crewmember's lifetime dose, they may be of particular concern for pregnant workers who have stricter recommended dose limits to their conceptus than non-pregnant workers. 

Overall, flight crews receive among the highest occupational doses of ionizing radiation in the United States, though estimated annual doses generally remain below recommended limits. Questions remain about what cumulative exposure may mean for long-term health. Some studies have reported elevated rates of certain cancers among pilots and flight attendants, but the evidence is not conclusive enough to determine whether occupational radiation exposure is the cause. Other aspects of aviation work, including other types of exposures and circadian disruption, may also affect health outcomes. 

Workers Role in Tracking 

The Federal Aviation Administration has recognized radiation exposure as an occupational consideration for flight crews for decades and provides recommended guidance along with its Civil Aerospace Research Institution (CARI) radiation dose estimation models, which estimate exposure based on flight route, altitude, duration, and timing. However, there are no requirements to the airlines to follow these recommendations.  

Casey Canfield, associate professor in engineering management and systems engineering at Missouri University of Science and Technology and member of the committee that wrote the National Academies’ report, emphasizes this point, stating, "Existing tools can help crewmembers understand the dose received from an individual flight, but there is no system for tracking the cumulative exposure. That’s a problem because the risk is cumulative. There is very little risk from an individual flight, but over a career, that cumulative exposure may be associated with health risks, warranting monitoring over a career." 

Flight crewmembers who want to understand their occupational exposure are often left to estimate and record it themselves. The report found that this lack of systematic tracking also limits researchers' ability to study possible connections between cumulative radiation exposure and long-term health. 

Many previous studies have relied on measures such as years worked or hours flown rather than individual exposure records. A centralized dose-tracking system could give flight crews more useful information regarding their occupational exposure and considerations on how to manage it, if necessary, while providing researchers with the necessary data to better understand occupational radiation exposure and associated health impacts over time. 

Shared Knowledge Could Move Toward Stronger Protections 

The authoring committee recommended that the FAA lead a phased effort to strengthen occupational radiation safety in commercial aviation. Among its recommendations are improving accessibility to the FAA's CARI models through a more user-friendly web-based application, requiring U.S. airlines to establish radiation safety programs, expanding education and training for flight crews, including clearer guidance for pregnant crewmembers as part of those programs, developing a centralized system for tracking cumulative radiation exposure, and investing in long-term characterization of radiation in the flight environment. 

The committee concluded that many of the tools needed to improve occupational radiation safety already exist. Rather than identifying a newly discovered risk, the report argues that a long-recognized occupational exposure should be managed more consistently. Implementing its recommendations would require collaboration among the FAA, airlines, labor organizations, researchers, and other federal agencies. Such coordination would give flight crewmembers better information about the radiation they accumulate over a career while strengthening the scientific foundation for future research.