Check the UV index right now for your location. Hourly UV forecast, peak UV times, protection window, and sun protection tips — anywhere in the world. UV radiation is only one form of radiation and it is measured on a scientific scale called the electromagnetic (EM) spectrum. UV radiation is only one type of EM energy you may be familiar with. uv is backed by Astral, the creators of Ruff. Install uv with our official standalone installer: Then, check out the first steps or read on for a brief overview. uv may also be installed with pip, Homebrew, and more. See all of the methods on the installation page. Ultraviolet (UV) radiation is a form of non-ionizing radiation that is emitted by the sun and artificial sources, such as tanning beds and germicidal lamps. While it has some benefits for people, including the creation of Vitamin D, UV can also cause health risks. Learn about ultraviolet light, which is also known as UV light, ultraviolet radiation, or black light. See its categories and effects. Ultraviolet (UV) radiation covers the wavelength range of 100–400 nm, which is a higher frequency and lower wavelength than visible light. UV radiation comes naturally from the sun, but it can also be created by artificial sources used in industry, commerce and recreation. Ultraviolet (UV) radiation is undetectable by the human eye, although, when it falls on certain materials, it may cause them to fluoresce —i.e., emit electromagnetic radiation of lower energy, such as visible light. Many insects, however, are able to see ultraviolet radiation. Ultraviolet (UV) light has shorter wavelengths than visible light. Although UV waves are invisible to the human eye, some insects, such as bumblebees, can see them. This is similar to how a dog can hear the sound of a whistle just outside the hearing range of humans. Exposure to ultraviolet (UV) radiation is a major risk factor for skin cancers, including basal cell carcinoma, squamous cell carcinoma, and melanoma. Learn what UV radiation is, how exposure happens, what research says about its health effects and cancer risk, and steps you can take to limit your exposure. What is UV radiation? UV radiation is present in sunlight and constitutes about 10% of the total electromagnetic radiation output from the Sun. It is also produced by electric arcs, Cherenkov radiation, and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights.