[bsder]

As I understand it, the point of 222nm is NOT to sterilize organic tissue directly.

The point of 222nm is to able to use it for sterilization in things like air return ducts, industrial cleaning equipment, etc.

Since 222nm is relatively "safe", you don't have to worry some idiot opening up a system, giving himself a gigantic flux of UV in the face, and winding up in the ER for cornea burns.

Consequently, your maintenance people don't need special equipment or extra training.

[byb]

This is the point of mechanical/electrical interlocks to prevent exposure to energized UVC. This is why I find the attempt to make 'far uv' safe in the public conscious even more dangerous.