Ultraviolet rays are suspected in ozone layer destruction, one of the global environmental issues that has been focused on in recent years.

Near an altitude of 25 km, there is a rather thick ozone layer of 15 parts per million (ppm). This layer absorbs ultraviolet rays with wavelengths of 350 nm and less, thereby preventing them from reaching the earth's surface, where they would devastate life. Part of the ozone layer is being destroyed by chlorofluorocarbons (CFCs) that are used in refrigerators and air conditioners. "Ozone holes," where the level of ozone is extremely low, can be observed in the Antarctic and other places.