I have been studying the effect of UVC (ultraviolet C) on humans. There are two different explanations for the effects on humans. An article on the Health Physics Society website states that UVC cannot penetrate human dead skin. But, on the other hand, there are a few sources that mention that UVC is the most dangerous wavelength that can cause skin cancer. Please explain further or provide any theory/calculation why UVC cannot penetrate human skin even though the energy is stronger than UVB and UVA.


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