Synonyms in a broader sense
UV – light, ultraviolet light, ultraviolet radiation English: uv – radiation
Introduction
The term UV radiation is an abbreviation for “ultraviolet radiation” (also: ultraviolet light or UV light) and describes a certain wave range of light. The most important natural source of UV radiation is the sun, but others can also be the origin of UV light (besides, in the meantime it is also possible to produce artificial UV radiation, for example, to emit UV light). One can divide the sunlight into three areas: On the one hand the radiation visible for us, on the other hand the invisible infrared radiation and the ultraviolet radiation. Ultraviolet means “beyond violet”, which means that the UV light in the color spectrum practically starts below the limit at which people can no longer perceive the color violet.
- Stars,
- Aurora borealis and
- Pulsars
- UV laser
- Welding equipment and
- Mercury vapour lamps
Classification
The UV radiation itself can also be divided into three elements. Firstly, there is UV-A radiation with wavelengths of 315 to 380 nm. This is hardly ever filtered out by the ozone layer and is therefore the part of UV radiation that reaches us on earth most strongly. The UV-B radiation with wavelengths between 280 and 315 nm is intercepted by the ozone layer to almost 90%, so it reaches us only less. UV-C radiation with wavelengths between 100 and 280 nm (below 100 nm one also speaks of “extreme UV light”, EUV, XUV) is almost completely absorbed by the ozone layer and therefore does not actually reach the earth.
Intensity of the UV – radiation
The more short-wave light is, the more energetic it is and can achieve a higher biological effectiveness. How intensive the UV radiation is, however, also depends on other factors, including the time of year (UV radiation is strongest in spring and summer), the time of day (intensive UV radiation occurs mainly at midday), the geographical location (there is a high level of UV radiation, especially at the equator), the state of the ozone layer (a higher proportion of UV radiation penetrates through to humans below ozone holes) and the sky (clouds are also able to absorb a small proportion of UV radiation). In addition, the environment also affects the intensity of UV radiation, since snow or water surfaces, for example, can scatter UV radiation, which also increases its intensity.