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Perhaps 222nm is absorbed primarily by dead skin cells - but why is skin the only tissue mentioned? It says nothing about damage to corneal and conjunctival tissues. Eye damage is a major hazard for humans with UV light in particular. "Very low risk" simply doesn't track. "Reduced risk" might.

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Eyes, like skin, have a layer of dead cells, and sufficiently short wavelengths can't get through. If you shine enough 222-nm into eyes they'll get dry and uncomfortable, but we're talking about much lower levels.

Here's an example of some of the research here, where they shined 222 nm vs 254 nm into rat eyes and looked for corneal damage. While 254 had some harmful effects 222 was fine: https://www.tandfonline.com/doi/abs/10.1080/10715762.2019.16...

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