Ultraviolet radiation is electromagnetic radiation whose wavelength ranges from the border of the violet spectrum to the border of x-rays. It is worth noting that the first mention of this phenomenon arose in the thirteenth century. It was then that Indian philosophers in their writings described the atmosphere, which contained violet rays invisible to the naked eye.
At the end of the 17th century, when the infrared spectrum was discovered, scientists all over the world began to study radiation at the opposite end of the light spectrum. That is exactly how the ultraviolet radiation was first discovered and studied. In 1801, I.V. Ritter discovered that silver oxide darkens faster when exposed to invisible light belonging to the violet part of the spectrum.
Around the same time, scientists came to the conclusion that light consists of three separate parts. This is the so-called visible light (or lighting component), infrared and ultraviolet radiation (it is also regenerative). In the future, scientists actively studied the effect of ultraviolet radiation on a living organism, as well as its role in nature.
Ultraviolet radiation: properties and classification
Today, ultraviolet rays are usually divided into three main types, each of which has its own characteristics:
- UV-C, which are better known as gamma radiation. It is worth noting immediately that they are very dangerous for the health of the human body. Fortunately, such radiation is almost completely absorbed by oxygen, the ozone ball and water vapor as it passes through the planet’s atmosphere.
- UV-B is another type of radiation that is also almost completely absorbed by the Earth’s gas envelope. The surface reaches no more than ten percent. By the way, it is under the influence of these rays that melanin is produced in human skin.
- UV A. This type of ray almost completely reaches the surface of the planet and is practically harmless to living organisms. With prolonged exposure, it causes accelerated skin aging.
As for the properties, for starters it is worth noting that ultraviolet radiation is invisible to the naked eye. In addition, it has high chemical activity and is a catalyst for many natural reactions. High concentrations of ultraviolet have antibacterial properties. And, of course, we must not forget that in small doses it positively affects the human body.
Ultraviolet radiation and its effect on the human body
It is immediately worth noting that it is ultraviolet rays that contribute to the formation of vitamin D in human skin, which, in turn, ensures normal calcium metabolism in the body and a good state of the skeletal system. In addition, the rays of this particular spectrum are responsible for the biological rhythms of a living organism. It is proved that ultraviolet in the blood increases the level of the so-called "hormone of vivacity", which provides a normal emotional state.
Unfortunately, ultraviolet radiation is useful and necessary only in small doses. Excessive exposure to these rays causes the opposite effect. For example, with prolonged exposure to the skin, ultraviolet accelerates the aging process, and in some cases causes burns. Sometimes radiation leads to cell mutations, which can subsequently degenerate into malignant tumors.
Enhanced ultraviolet radiation also adversely affects the retina, causing a burn. Therefore, in the sunny season, it is simply necessary to use special safety glasses.