Aerospace Radiation Safety: A Regulatory and Scientific Gap.
As cruising latitude rises, Earth's magnetic field weakens, providing a thin atmosphere and less cosmic radiation shielding. Generally, commercial airlines cruise between 25,000 and 41,000 ft with the radiation dose rate fluctuating between 2 and 12 µSv/h based on the cruising latitude and solar particle events (SPE). Among all the cruising routes, polar and transpolar routes experience the maximum radiation exposure, which can exceed 80 µSv/h during the SPE at high latitude. For better understanding, if we compare it to chest X-rays using a real-world example, a one-way May 2024 flight from San Francisco to Paris recorded a radiation dose rate equivalent to four chest X-rays during the Gannon solar storm.
Why is it so crucial? Typically, an aviation crew logs 800 to 1,000 flight hours a year, resulting in longer repetitive radiation exposure, which can damage DNA sequences, leading to higher long-term cancer risks.
Beyond aviation, with ISS retirement in 2030, there is a greater likelihood of crewed missions extending into cislunar space, leading to a significant increase in cosmic radiation exposure. Despite the awareness of the health risks of prolonged radiation exposure, international standards lack a framework to harmonize safety standards for flight and space crew. Closing this regulatory gap is essential to protecting the people who fly our skies and explore our solar system.
- Aviation: elevated incidence of breast cancer, melanoma, and reproductive risks documented in long-tenured flight crews.
- Spaceflight: scarce human data; cislunar crews face GCR and SPE exposures with no agency-binding limits.
- Regulation: EU EURATOM and ICAO frameworks exist for aviation, but coverage is uneven, and dose monitoring is inconsistent.