摘要： Ultraviolet Radiation (UVR) is significantly higher at aviation altitudes with respect to sea level due to weaker attenuation by the atmosphere. At higher flight levels clear sky conditions cause permanent direct sunlight during the daytime hours. The transmittance of cockpit windshields and the UVR exposure of pilots have become subject of research due to the association of UVR with cataracts, carcinoma, melanoma and accelerated skin aging. In this work, the spectral properties of several windshields under flight conditions are investigated. Only one of the investigated windshields showed good UV-A attenuation. Furthermore, the altitude dependence of UV-A irradiance behind a windshield was measured with high spatial resolution. Measurements of the maximal UV irradiance behind the windshield surfaces and at the pilot’s position are compared to the recommendations by the International Commission on Non-Ionizing Radiation Protection. Some recommended limits were exceeded at the surface of the windshields with direct sunlight and a large field of view. At the pilot’s position, with a more realistic field of view, the unweighted recommended level could have been exceeded within tens of minutes by looking in the direction of the Sun without visor or other protective measures. The weighted recommended maximal UVR exposure was not exceeded, neither with the use of the visor at the pilot’s position nor without it. The use of the visor for filtering direct sunlight was very effective in terms of UV-A reduction.