UV-C Light / UV-C Radiation
The short-wave UV-C radiation is almost completely absorbed or reflected by the earth’s ozone layer, so almost nothing arrives on the earth. A good thing is because the high-energy, short-wave UV-C radiation is harmful. It can penetrate the tissue layers of the skin (and the eye) and lead to changes in the cells there. In the worst case, the genetic information (the genes) is affected, so that the cells can either no longer divide – or they begin to divide in an uncontrolled manner (this is then called a malignant tumor, i.e., cancer). It is all the more important that we humans make sure that the ozone layer is not destroyed.
Ultraviolet radiation, in short: UV radiation or the UVGI system (ระบบ uvgi which is the term in Thai) is a part of the electromagnetic radiation that is not visible to humans, but for some animal species (e.g., bees). The electromagnetic radiation around us comes primarily from the sun.
Only the part of the electromagnetic radiation in the range between 380 and 780 nanometers is visible to the human eye.
The term UN-C light is incorrect because “light” is the part of electromagnetic radiation that we humans can perceive with the help of our eyes.
Why Is UV-C Radiation Harmful
The shorter-wave radiation, the more energetic it is. You can think of it as if a tennis ball machine fired balls: the faster and harder it fires individual balls, the harder it is to fend them off.
The high-energy radiation can damage the highly sensitive human cells. The most dangerous is the change in the genetic material (DNA). The human skin tries to protect itself against UV radiation and forms a dye (melanin) that darkens the skin. This is intended to absorb parts of the UV radiation so that they cannot penetrate the lower-lying cell layers.