Our eyes are constantly exposed to UV radiation – even when the sky is heavily clouded. Up to 40 percent of exposure to UV radiation even arise if you do not stay in direct sunlight. Snow, water, sand, clouds, fog, streets, and glass facades, too, reflect UV rays. These slanting rays fall into the eye without your perception of them. Low sun results in strong dazzling reflections. Light reflections of the water increase the UV light by 20 percent, snow even by 80 to 90 percent. In the mountains, the intensity of UV radiation increases per altitude of 1,000 metres by 10 percent.
The large pupils and brighter eye lenses of children absorb even more UV rays than the eyes of adults. Thus, even more UV rays get to the retina and damage the sensitive photoreceptors.