Some SAD lights do give off some UV rays while some SAD lights do not give off or at least filter the UV rays.
SAD lamps or lights that are designed for also treating skin disorders may give off UV rays but those SAD lights that are used for depression or the winter blues are usually made to filter out the UV rays they give off.
However you should never look directly into the the SAD lamp or light no matter what type of SAD light you have because they can potentially damage your eyes.
When the SAD lights or SAD lamps are used correctly they pose no health issues and can actually help you with depression.
I have a SAD lamp that does not emit any UV rays and it really helps me on cloudy, rainy days or the winter months when it's very cold and dark outside.
I used to get depressed a lot during cloudy, rainy days and in the winter but after using a SAD lamp the depression has gone away as long as I'm near my SAD lamp often.