You might be getting some UV exposure long after the sun goes down — some new fluorescent light bulbs give off UV light.
Fluorescent light bulbs are everywhere now that people are trying to be more green. Most popular are the ice-cream-twist compact fluorescent bulbs called CFBs. CFBs create light by energizing a gas and exciting a phosphorous coating on their glass. The coating prevents most of the ultraviolet light from reaching you, but not entirely; some UV radiation leaks out of any fluorescent bulb. In some CFBs, the emission of UV light is so high that it exceeds the safety limits of the International Commission of Non-Iodizing Radiation.
So, should you be applying sunscreen before turning on your CFB reading light at night? No. Nor should you switch your CFBs back to energy wasting incandescent bulbs. The amount of UV exposure that you get from the light bulb is small compared to the UV exposure you get from just being outside; for most people it is not significant.
However, some people are exquisitely sensitive to ultraviolet light. Auto immune diseases such as lupus, inflammatory disease such as rosacea, and certain drugs such as HCTZ can be triggered by even small amounts of UV light from CFBs.
If you are particularly sensitive to UV, then select CFBs that have a double envelope instead of single, as it will block most of the UV light. And always stay at least one foot away when using fluorescent bulbs of any sort.
Also, remember to sit back from your TV (which my mother taught me to do when I was a kid). Of course, now with HDTVs, you get the best picture when you’re sitting a distance of 3 times the diameter of your TV. If you just bought a 60 inch HDTV, you might need to be in your neighbor’s living room to watch it. This, fortunately, should be safely away from any radiation.
Photo: Steven Fernandez (flickr)