Ultraviolet means "beyond violet" (ultra meaning "beyond" in Latin), and violet being the color of the shortest wavelength of visible light.
Ultraviolet (UV) light is electromagnetic radiation
UV light has a wavelength that is shorter than that of visible light, but longer than x-ray light. It is invisible to the human eye.
Categorized by wavelength
UV can be subdivided based on its wavelength, as measured in nanometers. It is typically divided into near UV (200-380nm) and extreme or vacuum UV (10-200nm)
The sun is the greatest source of UV light
The sun emits ultraviolet light in both near UV and vacuum UV wavelengths, but because of absorption in the atmosphere's ozone layer, 99% of the ultraviolet light that reaches the Earth's surface is 315-380nm (UV-A).
Proven and trusted
UV is widely used to disinfect drinking water and wastewater worldwide, and has been for many years. UV is also extensively used for industrial applications including food & beverage, pharmaceutical, and semiconductor manufacturing.