I too have been concerned with the exposure over time to UV light
especially with regard to potential eye damage. The eye can be damaged
by uv radiation and the damage depends on the wavelength. Wavelengths
<300nm typically this takes the form of exposure to an arc welding can
cause a burn of the outer layer of the eye or a keratitis. This is an
acute problem causing eye pain several hours after the exposure.
Wavelengths of 300-400nm can be transmitted thorough the cornea and
absorbed by the lens where they can cause cataracts.
I discussed this problem with an optometrist who specializes in
occupational eye injury. He told me that he had not seen nor read
about eye injuries due to prolonged UV exposure in the printing
/lithography industry which was somewhat reassuring but I personally
either shield off the uv light source, wear protective eyewear or
avoid being in the room when the uv lights are on. In other words take
reasonable precautions.
Larry Shapiro