Ultraviolet Radiation (UV Radiation) is a form of electromagnetic radiation in the wavelength range between visible light and X-rays (from 10 nm (30 PHz) to 380 nm (750 THz), shorter than visible light (= light purple) end of the range of colours) that comes from the sun and man-made sources like tanning beds and welding torches, and can be seen by humans wavelength. The Ultraviolet Radiation has some benefits for people, including the creation of Vitamin D, and most of the UV radiation is absorbed by the ozone molecules in the upper atmosphere, but a potentially dangerous amount passes through the ozone hole to cause cataracts, skin cancer, suppression of the immune system, leaf damage, and reduced yields in some crops. (Refer to the UV Index (UVI))
Reference Definition by Greenfacts.org: Ultraviolet Radiation is an electromagnetic radiation of shorter wavelength than visible light but of longer wavelength than x-rays, i.e. ranging from approximately 400 nm to 100 nm. The most common source of ultraviolet radiation is the sun, but it can also be produced artificially by UV lamps. UV radiation is divided into three bands: UVA, UVB, and UVC. All three bands are classified as a probable human carcinogen. UVA: Long-wavelength UVA covers the range 315~400 nm. Not significantly filtered by the atmosphere. Approximately 90% of UV radiation reaching the Earth’s surface. UVA is again divided into UVA-I (340 nm~400 nm) and UVA-II (315 nm~340 nm); UVB: Medium-wavelength UVB covers the range 280~315 nm. Approximately 10% of UV radiation reaching the Earth’s surface; UVC: Short-wavelength UVC covers the range 100~280 nm. All solar UVC radiation is absorbed by the ozone layer.
Related Definitions in the Project: The HSE Management; Property and Unit
