Aircrew are exposed to ionizing radiation at cruising altitudes, where exposure levels depend on altitude, latitude, and flight duration. Astronauts experience substantially higher exposure due to cosmic radiation of greater energy and linear energy transfer. This review summarizes current knowledge on occupational ionizing radiation exposure among flight and space personnel. A literature search of peer-reviewed and institutional sources was conducted to identify data on exposure levels and regulatory frameworks. Relevant publications and reports from international agencies were examined to compare aircrew and astronaut exposure contexts. Findings indicate that commercial aircrew experience exposure levels well below the established occupational limits, although variations occur depending on flight profiles and routes. For astronauts, space agencies define career dose limits that account for mission type and environment, ensuring exposure management tailored to specific mission conditions. Average effective doses and equivalent doses are reported and discussed for respectively aircrew and astronauts. These limits are established to maintain radiation exposure below levels considered acceptable for professional safety, thereby ensuring regulatory protection under normal operational conditions.
- Open Access
- Review
Occupational Exposure to Cosmic Ionizing Radiation of Aircrew and Astronauts
- Sara Colazzo 1,*,†,
- Mitia Stiscia 1,†,
- Davide Marotta 2,3,
- Alberto Modenese 1
Author Information
Received: 04 Feb 2026 | Revised: 01 Apr 2026 | Accepted: 01 Apr 2026 | Published: 20 Apr 2026
Abstract
Keywords
cosmic ionizing radiation | occupational exposure | aircrew | astronauts
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