Since the ultraviolet rays radiation with a wavelength less than 200 nanometers will be strongly absorbed by the air,
we basically only study ultraviolet rays with wavelengths above 200nm in our applications.
Moreover, the current technological development of the LED industry is not equipped to support the commercial use of ultraviolet products below 200nm.
For promotion, we can divide ultraviolet rays into the following three commonly used wavelengths:
UVA（400nm–315nm）
UVB（315nm–280nm）
UVC（280nm–200nm）

https://www.tank007.com/product-category/uv-flashlight/

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