The sun is the major source of ultraviolet light, and most people with lupus know they should avoid the sun and use sunscreen when outdoors. But UV rays also come from indoor lighting, like the new energy-efficient compact fluorescent light bulbs which are increasingly used in residential and commercial buildings. Dr. Richard Sontheimer, professor of dermatology at the University of Utah Health Sciences Center conducted a recent study on the amount of ultraviolet light emitted from both the old fashioned incandescent light bulbs and the new fluorescents.