Introduction: An evaluation of the ultraviolet (UV) flux incident on the Martian surface is important for a number of issues. UV-induced photolysis of wa-ter changes the chemistry of the soil and atmosphere, inducing its oxidizing nature [e.g., 1]. Alternatively, UV may directly affect surface chemistry by generat-ing silicate defects [2]. The human cornea blocks solar radiation with wavelengths shorter than 290 nm (). 3 The lens absorbs essentially all the UVR and, age dependently, shorter VIR wavelengths that are transmitted by A greenhouse's glass enclosure allows visible light to enter and be absorbed by the plants and soil. The plants and soil then emit the absorbed heat energy as infrared radiation. The glass of the greenhouse then absorbs that infrared radiation, emitting some of it back into the greenhouse and thus keeping the greenhouse warm even when the There are two types of UV radiation from the sun that cause damage that can lead to skin cancer: UVB rays, which mainly cause sunburn, and UVA rays, which mainly cause tanning and premature aging. All glass windows block UVB radiation fairly well. Windshields are made of a laminated glass that can block over 90 percent of UVA radiation, too. Originally Posted by Jedi. CR-39 does in fact block UV light, but only up to 360nm. I believe the big reason that CR-39 does not block up to 400nm by itself is the UV filter at that point would cause the lens to be tinted light yellow, which is cosmetically unappealing. CR39 used to go yellow in the 1970's because of UV influence. After absorbing UVB radiation previtamin D 2 is produced. Its absorption spectrum with a wavelength maximum at 260 nm overlaps the UV absorption spectrum for both DNA and RNA and thus would be able to protect DNA and RNA from photodamage (Fig. 2). 2 When previtamin D 2 is exposed to UVB radiation it is converted to tachysterol 2 which has a UV absorption spectrum with a wavelength maximum at Approximately 4 percent of the total radiation output from the sun is as UV, and most is as UV-A. In greenhouses, transmission of UV depends on the glazing material. Ordinary glass transmits 65 to 75 percent of UV-A but 3 percent or less of UV-B. Most plastics used to glaze greenhouses contain UV stabilizers to retard their degradation, but Photographic film responds to ultraviolet radiation but the glass lenses of cameras usually block radiation shorter than 350 nm. Slightly yellow UV-blocking filters are often used for outdoor photography to prevent unwanted bluing and overexposure by UV rays. For photography in the near UV, special filters may be used. .

does glass block uv radiation