EEPROMs with two Es are Electrically Erasable... you're not gonna wipe those in a UV box. Single E are Erasable with UV.
Now UVC is the most highly energetic and you get your EPROMs erased in a short time. UVB will still do it but it will take a lot longer, even UVA will eventually do it. It's also a function of distance to the source so you get the most energy per unit area.
It's a bit like toasting marshmallows on a camp fire. If you've got a really roaring large fire that you can feel your hair crinkling if you get within a couple of feet of it, you can get your marshmallow toasted very quickly and you don't even have to get it that close, starts happening a foot away. That's like UVC... Then say a "normal" small fire, you have to get it a lot closer, find the right glowing coal and carefully rotate and expose marshmallow to heat. UVB.. then there's a tealight candle... you can theoretically roast a marshmallow on it, but you have to get it super close and it takes a very long time. UVA
So if you get a UV cleaner and it gives times in minutes for cleaning, it's probably UVC and keeping the window exposed at a close distance to the source will erase the EPROM in minutes also. If it gives times in hours, it's probably UVB and doing single EPROM per source, with it right up to it, will clear it over many hours. ... UVA is probably not worth bothering with vs leaving chips on a window ledge in full sun for a few days.
Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.