UVB (315nm-280nm):
Medium wavelength with medium penetration, its shorter wavelength part will be absorbed by transparent glass.
Most of the medium-wave ultraviolet rays contained in sunlight are absorbed by the ozone layer.
And only less than 2% can reach the surface of the earth.
UVB ultraviolet rays have an erythema effect on the human body
It can promote the metabolism of minerals and the formation of vitamin D in the body.
Ultraviolet rays of UVB wavelength are mainly used in medical treatment, such as skin diseases.

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