I see slightly into the infra-red end of the spectrum, and proved it repeatedly in film photography class. When we were rolling negatives for small batch developing in full darkness I could see my classmates, and if they dropped something I could pick it up and take their hand and put the whatever in their hand.
The downside is my resolution in IR requires total darkness, and is very very faint. I didn't believe that I was doing it until I had several experiences with it and some conversations with classmates. I have met another person who also reports a similar experience, so I have to believe it is not terribly uncommon, just uncommon to recognize and not all that useful for most people. I would be unaware of this ability if I never took film photography.
Because your experiences in the UV end of the spectrum are obvious enough during full light I expect that projecting a large rainbow from a prism on a wall and having several people mark the lowest and highest portions of the spectrum will give you results you will find useful. Have them also mark individual color bands and you can calibrate the setup to other people in a repeatable manner.
Phil