Broken compact fluorescent bulb

February 27, 2008 2:07 AM

I broke a compact fluorescent light bulb in my bedroom. Rudimentary cleanup, but I'm must go to bed, and my husband's already asleep in there. I saw the scary "leave the room for 15 minutes" mercury warnings on the government cleanup page. Anybody know the science? How bad is this?

Some shards in the carpet. I've cleaned up the shards I could, probably still dust in the carpet; I've opened a window. Suggestions for more cleanup in the morning? Range of "how bad is this"? If it's bad, what will happen (what should we watch for)? No kids or pets involved.

posted by LobsterMitten to health (10 comments total)

Don't worry about it. It's a tiny speck of mercury, which will evaporate by itself and blow away out the window in a few days at most. During that time the air mercury levels right by the actual spill point will probably exceed some safety margin or other, but the dose received by anybody in the room would be trivial even if you tried to concentrate the mercury by sealing the room up.

Organic mercury compounds are Bad News. Metallic mercury, while still toxic, is not nearly so big a deal even if you've spilled a whole thermometer-worth of the stuff.

(That'd be something like 1 to 3 grams of mercury, by the way. A compact fluorescent lamp will contain single-digit milligrams of mercury.)

You can read about my own Mercury Spill Cleanup Adventure here.
posted by dansdata at 2:33 AM on February 27

This was published a couple days ago:

The Maine study, which shattered 65 bulbs to test air quality and clean-up methods made these recommendations: If a bulb breaks, get children and pets out of the room. Ventilate the room. Never use a vacuum -- even on a rug -- to clean up a compact fluorescent light. Instead, while wearing rubber gloves, use stiff paper such as index cards and tape to pick up pieces, then wipe the area with a wet wipe or damp paper towel. If there are young children or pregnant woman in the house, consider cutting out the piece of carpet where the bulb broke. Use a glass jar with a screw top to contain the shards and clean-up debris.

posted by Partial Law at 5:39 AM on February 27 [3 favorites]

Thank you both!

Dansdata, will it really all just evaporate, given some time? So, for example, we don't need to worry about telling our landlords to replace the carpet? All my sense of proportion is blown, here.

With these lamps, is there powder/solid mercury (or liquid mercury?) on the inside, which then releases vapor over a period of time if it's exposed to air? Maine's report talks about this stuff as being "mercury sources" that can stay in a rug over a long period of time; these are little solid bits of powder, or what?
posted by LobsterMitten at 12:18 PM on February 27

will it really all just evaporate, given some time?

Short answer: Yes

Long answer: The fluorescent tube's operation depends on the mercury being evenly distributed throughout the tube in a gaseous state.

It's a tiny amount, already in a gaseous state, and prone to re-sublimate if it's forced into solid (or liquid) form, which wasn't likely to happen in the first place. It's probably gone to the point of reasonable undetectability already.
posted by SlyBevel at 3:42 PM on February 27

...Meaning that you breaking the tube is extremely unlikely to force the gas mercury into a solid or liquid state. The fact that the tube decompresses when it breaks would strongly suggest that gases in it would simply become less dense in the new, larger, and less compressed environment.

Opening the window was a very good idea. I'd try to open more in the house to strategically get air flowing through that room for a day or two.
posted by SlyBevel at 3:45 PM on February 27

Thanks SlyBevel. I'm still kind of freaking out about the whole thing (but no other place to sleep in the house, so slept there last night)...

So is the cut out the piece of carpet if you have kids/pregnant women/pets; seal the debris and anything you used for cleanup into a mason jar and get that jar out of your house advice just overreaction (abundance of caution)?

How does the debris continue to generate more mercury if the only mercury in the thing to begin with was gaseous?
posted by LobsterMitten at 4:17 PM on February 27

The concern is that debris from the broken tube may have mercury clinging to it. Some fluorescents have a dust inside them. The dust and the phosphor coating on the glass would both be porous to some degree, and so could contain some level of mercury after most of the gas has dissipated.

But realistically, you probably eat more mercury in fish in a year than is on your carpet now. Especially if you're into sushi at all (which I am...I have to watch it!).
posted by SlyBevel at 5:02 PM on February 27

...and the mercury in the fish is the amazingly toxic organic compounds, not the far less toxic metallic type.

I think the super-hysteria over trivially tiny mercury "spills" is the result partly of people like the amalgam-haters (who're convinced that mercury in amalgam fillings causes everything from multiple sclerosis to rainy days; see also aspartame, which has its own band of followers who believe it is the cause of every illness known to man), and partly of a chain of cover-your-ass decisions.

Everybody along the chain - a few who actually know what they're talking about, plus lots of administrators and managers and journalists - takes the safest possible course of action to make sure they don't get sued. The end result is homeowners being seriously instructed to take the same sorts of precautions if they break a thermometer - or even a CFL - as you actually need to take if you've just covered your lab floor with five pounds of mercury.

(I also had a shot at the mercury-in-fish numbers, by the way, here.)
posted by dansdata at 6:52 PM on February 27

Thank you guys - I appreciate it.
posted by LobsterMitten at 7:20 PM on February 27

Wow, I just broke a CFL in the bedroom while painting and was about to ask THIS SAME QUESTION. Thanks you, AskMefi Search.

In my case I had to choose between leaving the room immediately like you are supposed to or finishing painting. I was using semi-gloss and had just finished the trim on two weirdly shaped areas... and was running out of semi-gloss... so if I had quit I would have had to both start over and buy more paint.

Sadly, I decided that the inconvenience of buying more paint and re-doing all the trim was worse than breathing elemental mercury for 20 minutes so I opened the windows, put the broken glass in some plastic bags and placed them outside... and then finished painting before leaving the room.

I suck. Suck mercury.
posted by Justinian at 1:58 PM on February 29