Your questions are all over the map.
I think two points will help.
#1:
Different bug species are attracted to different kinds of light sources, UV seems to attract the greatest percentage of them.
https://www.quora.com/Why-are-some-insects-attracted-to-light
Light has different names depending on frequency (wavelength). Starting from long wavelength to short, here are some names applied to the "kinds" of light:
Radio
Microwaves
Visible light (a very tiny part of the spectrum)
UV
X-rays
Gamma rays
#2
UV - Skin damage is determined by:
the intensity of the light,
the wavelength,
bare skin exposure time.
ILT's (insect light traps) have been tested for human damage potential. ILT's give off UV-A (UV-A: 315–400 nm (nm - nanometers - is a unit of length measurement for wavelegth)), and are used indoors in food processing plants. The exposure of UV-A over an 8 shift from these traps indoors is less than what you get from the sun during a short walk on a sunny day.
I think you can read this article:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4867860/
To be clear, you may be confusing this (UV-B) with light traps (UV-A):
BTW: UV-B ( not what an ILT makes) can damage skin but it also makes Vitamin D. And getting UV exposure outside as a Vitamin D source may not be a good choice for some people. An easy read:
http://www.skincancer.org/healthy-lifestyle/vitamin-d/make-vitamin-d-not-uv-a-priority
So. Not all UV light has a good or a bad effect on humans. It is complicated like most of life.
If you are afraid of UV light traps, do not use them.