Re: Are there any dangers of using a black light as a night light?

A "black light" is so named because a lot of the radiation it emits is 
not visible to the human eye, nor detectable as warmth as are 
infrared rays. The radiation (light, if you will) emitted is ultra-violet, 
also known as UV. These rays are potentially hazardous if absorbed 
in large enough quantities. The UV component of sunlight is what 
gives you a sunburn at the beach and can raise your risk of skin 
cancer. Not knowing anything in particular about the black light that 
your son is using as a nightlight, I recommend that he stop using it 
as such immediately, certainly if he is using it to illuminate the 
bedroom of his children at all. I repeat: he should stop using it 
immediately. Such use is totally inappropriate.