Fluorescent disposal

Are these lights safe? Where do you put them when they burn out?

I've heard that compact fluorescent lights contain mercury. Is this true? How do I deal with fluorescent disposal? Are these lights safe to use?

Answer from Green Energy Efficient Homes

In fluorescent lights, a current regulated by a ballast is passed through mercury vapor. The current excites the mercury vapor, which emits photons in ultraviolet light. Since ultraviolet light is not part of the visible spectrum, fluorescent lights are coated with a phosphor that absorbs the ultraviolet light, and that then fluoresces, or emits photons of visible light.

The amount of mercury in fluorescent bulbs is quite small - about 1/100th that found in a mercury thermometer. There are about 5 milligrams in a CFL and around 50 mg in a long-tube fluorescent. As long as the bulb remains intact there is no risk from the mercury.

People throw out around 600 million fluorescent bulbs a year, which does create a problem in terms of mercury contamination. But the bulbs can be safely recycled, and you are better off using these bulbs and then recycling them through a fluorescent disposal service, than sticking with incandescent bulbs. That's because so much of our electricity is generated from coal, which not only contains mercury but produces carbon dioxide, a greenhouse gas. While the electricity saved over the 8,000 hour typical life of a compact fluorescent means less mercury released by coal-fired plants, it's still not as much as the mercury contained in the compact fluorescent bulb. But this misses the point: if you are going to do the environmentally friendly thing, you're not going to throw that CFL in the garbage when it burns out - you're going to recycle it safely. That way you reduce both mercury and CO2 emissions into the environment, which is what we should all be trying to do.

So by all means switch your lights to fluorescent lights - just use a fluorescent disposal service to recycle them when they die, and tell everyone you know to do the same!

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