Which statement is correct about ionizing radiation exposure for aircrew?

The statement that the dose of ionizing radiation exposure is higher at the poles is correct because of several factors related to the Earth's magnetic field and atmosphere. At higher latitudes, particularly near the poles, the protection against cosmic radiation diminishes. This occurs because the magnetic field lines converge at the poles, allowing more high-energy particles to penetrate the atmosphere compared to regions closer to the equator. Additionally, the thinner atmosphere at higher altitudes provides less shielding from cosmic rays, resulting in increased exposure to ionizing radiation for aircrew flying over these areas.

Understanding the geographic variation in radiation exposure is important for flight safety and health monitoring of aircrew. The other options do not accurately reflect key principles of radiation exposure relative to altitude, geographic location, or specific aviation operations involving aircrew.