Skin cancer is easy to prevent by not allowing the light to shine directly on anyones skin, and using non-UV reflective enclosures.

Ozone is already a known and easily tested quantity, and generally only happens at 240nm and lower wavelengths. So 222 as listed might produce some, but doesn't seem optimal (180nm seems better).

Found a paper - seems likely that is the case [https://onlinelibrary.wiley.com/doi/full/10.1111/php.13391]

Note scale on the first graph.

edit: ah hah, but many of these lamps have defects that can result in higher freq. light emission and high ozone production! See later parts of the paper.

Far-UVC (~205-222 nm) light can’t penetrate cell walls and thus does not risk DNA damage.

However, our skin heavily depends on friendly bacteria to do useful things. One concern that I have yet to see research testing is the impact of extended Far-UVC exposure on these microbial populations.

Human cells don't have cell walls.

My apologies, the membrane. I went and dug more into this to brush up on the exact specifics and the exact conclusion of the research was that less than 5% of the intensity of the light reached the nuclear envelope, thus avoiding DNA damage. This is the original study: https://ieeexplore.ieee.org/abstract/document/1341520/

However, while I was trying to find the specifics on the DNA damage, I found this: https://mdpi-res.com/d_attachment/ijms/ijms-23-09112/article...

My only grief with this article is the conclusion they draw from the yH2AX staining. I can see several possible reasons for observing the higher proportion of cells with it.

Other than that, the paper raises a boatload of serious points and definitely observes negatively impacted cellular function. I still think FarUVC has incredible potential but just like cellphone towers the exact specifics to interact with it safely need serious further study.