Re: Are 'Black Lights' harmful? Eyes, skin?

Peiman:

The phrase "black light" can refer to either ultraviolet (UV) or infrared (IR) lights. Most commonly the phrase "black light" refers to lights that emit 370 nm UV radiation, this frequency is called UVA, or "near UV".

IR lights are generally not hazardous because you will feel the heat before there is any real chance of injury.

UV lights can be quite hazardous, because they can cause damage without producing any real heat.
How dangerous a UV light is depends on:

• how strong the light is,
• what the frequency range of the light is,
• how close you are to it
• whether there is a barrier (like glass) between you and the light.

So the answer to the question of whether a "black light" is hazardous is, "it depends".

I would advise caution around UV lights unless you know that the strength is very low. Even with a low strength UV source I would advise appropriate eye protection.

Reference: Non-Ionizing Radiation, International Commission on Non-Ionizing Radiation Protection, 1996.

John Moulder
Radiation Biologist
Medical College of Wisconsin