Compact flourescent lightbulbs

OK, Wayne, help me understand how this works. A CFL contains about 3 to 5 mg of mercury, is that right? Is that in vapor form? When a CFL breaks, does the mercury get into the atmosphere as vapor, or is it a solid? I remember the little beads that would result from breaking a thermometer, is it like that? What causes it to vaporize?

The EPA tells you, if a CFL breaks, to open a window and leave the room for 15 minutes or more. Is the vapor going to dissipate in 15 minutes? Then will there still be solid mercury with the broken bulb? How can we tell if we have picked it all up? And what happens if we don't? Will it vaporize at room temperature over a period of time?

I assume it would be more hazardous for small children and small animals than for adults. I have replaced practically all of the light bulbs in my house with CFLs, and I have not had any problems with them so far. I am certainly not in a panic over this, but I do want to know what to do in the event one of them gets broken.

 

http://www.epa.gov/mercury/consumerinfo.htm

 

Yes, that is about the correct amount.

Usually, but that is patially dependent on the temperature. The higher the temperature the more the vapor just like water and water vapor.

Inside a house at the normal temperature range it should all be vapor. If not it will quickly evaporate.

It would be much much smaller amounts so if there were a bead it would be somewhere about the size if a point on a ballpiont pen.

Just like all other liquids, the temperature. For the longest time there was never a thought of mercury having a vapor pressure at ambient temperatures because it was a metal. Once it was discovered the view of mercury changed significantly.

It should dissipate to a safe level immediately but given the potential threat and the possible higher concentration encountered as the vapor diffuses it is a conservative estimate for time.

No, the amount is so small it will vaporize unless the temperature is very low, such as in an unheated garage in a cold winter. When the area heats to a 75+ F temperature it will vaporize.

What will be left will be glass and not mercury. As the total amount of mercury put into the bulb is a bead about the size of this period. It will vaporize fairly quickly.

At normal rrom temperatures, yes, it should be dissipated befroe the 15 minute mark.

Yes, it is a much greater concern for smaller/younger animals of all species.

As has been noted here, ventilate the area, stay away for 15 minutes (or more if you are a child), do not use a vacuum cleaner for immediate clean up, and be careful with the broken glass that you do not cut yourself.

I played with mercury a lot in highschool and college because at the tiem there was not the concern over the vapor as is now. I suffered no significant difficutlies .... 8) :lol:

I have something like 1.25 kilograms of mercury stored in my office we have recovered from our equipment coming back from the field. I also have the 2 year old daughter of one of my employees who loves to come into my office and "share" my lunch or snacks. I would not risk her health for any amount of money and I have nothing but eight foot flourescent lights throughout the building, in addition to the mercury we have recovered, and I do not fear for her safety from that hazard.

 

http://www.epa.gov/mercury/spills/index.htm

 

Halogen bulbs are up to 40% more efficient than ordinary incandescent bulbs. Also, halogen bulbs maintain 95% of their initial light output at end of lamp life. They also last around 1.5 times longer than incandescent. Stay away from the double-ended types used in torchiere fixtures, they're somewhat dangerous.

 

I thought so, I may have misread your original post thinking that you said halogen were more efficient than CFL. Had a mini fire once due to a halogen bulb (poorly designed fixture).

 

http://www.sciencedirect.com/scienc...serid=10&md5=15fd8ebd6ab1decac77a764a411d76b1

The results showed that 34% of the 160 individual total mercury concentrations exceeded 5 ng/m3 – the ambient air quality guideline value recommended by the WHO. The range of total mercury concentrations in the ambient air of Slovakia was: 1.13–3.98 ng/m3 (geom. mean 2.63) in the background area; 2.25–5.27 ng/m3 (geom. mean 3.64) in the agricultural areas; 1.73–20.53 ng/m3 (geom. mean 4.57) in the urban areas; and 1.53–39.85 ng/m3 (geom. mean 5.28) in the industrial areas. The highest mercury levels occurred in areas with metallurgical industry and coal combustion. The predominant form of mercury present in air was vapor mercury.

 

http://www.osha.gov/SLTC/healthguidelines/mercuryvapor/recognition.html

EXPOSURE LIMITS

* OSHA PEL The current Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) for mercury vapor is 0.1 milligram per cubic meter (mg/m(3)) of air as a ceiling limit. A worker's exposure to mercury vapor shall at no time exceed this ceiling level.

* NIOSH REL

The National Institute for Occupational Safety and Health (NIOSH) has established a recommended exposure limit (REL) for mercury vapor of 0.05 mg/m(3) as a TWA for up to a 10-hour workday and a 40-hour workweek. NIOSH also assigns a "Skin" notation, which indicates that the cutaneous route of exposure, including mucous membranes and eyes, contributes to overall exposure [NIOSH 1992].
* ACGIH TLV

The American Conference of Governmental Industrial Hygienists (ACGIH) has assigned mercury vapor a threshold limit value (TLV) of 0.025 mg/m(3) as a TWA for a normal 8-hour workday and a 40-hour workweek and considers mercury vapor an A4 substance (not classifiable as a human carcinogen). The ACGIH also assigns a "Skin" notation to mercury vapor [ACGIH 1994, p. 25].
* Rationale for Limits

The NIOSH limit is based on the risk of central nervous system damage, eye, skin, and respiratory tract irritation [NIOSH 1992].
The ACGIH has not published documentation for the current TLV for mercury vapor. The 1991 Documentation of Threshold Limit Values (6th edition) discusses the basis for the prior TLV of 0.05 mg/m(3), but does not discuss the current TLV for mercury vapor [ACGIH 1991, p. 881].

 

1 Milligram = 1000000 Nanogram

The lowest level listed is 0.025 mg/m(3) as a TWA for a normal 8-hour workday and a 40-hour workweek

Thus, the lowest level is 25,000 ng/m3 compared to the 5 ng/m3 – the ambient air quality guideline value recommended by the WHO.

From the Junkscience article ... The specialist found mercury levels in the bedroom in excess of six times the state’s “safe” level for mercury contamination of 300 billionths of a gram per cubic meter

The level noted by the specialist of 300 ng/m3 is 60 times the ambient air quality guideline recommended by the WHO and 0.012 of the lowest TWA listed. The actual levels measured were 6 times this limit or 360 times the ambient air limits or 0.072 of the lowest TWA.

Given mercury is a liquid metal with a vapor pressure of 0.00185 mm at 25 degrees C. This corresponds to a saturation concentration in air of 20 milligrams of mercury per cubic meter of air or 2.4 ppm which means the mercury would continue to vaporize until the saturation point. With adequate ventilation the saturation point would never be reached and all of the mercury would vaporize. A ~12' X ~12' X ~8' room will contain ~33 m3 in which a 3 mg weight of Hg were vaporized would correspond to a ~90909 ng/m3 concentration or nearly 4 times the exposure limit. Now if the air is replaced through ventalation the concentration will drop accordingly. A single slow replacement would in theory reduce the concentration to ~45,000 ng/mg which would only be accurate for the average. Each time the air volume is slowly replaced the concentration is reduced by one half on average. In a normal house the diffusion would be greater because there is not a complete seal, so the air is replaced even without the active ventilation and the ventilation can be more robust than this just by opening a window.

 

From The Johnston County Department of Utilities

A response from my email to the Johnston County Department of Utilities.

 

you're more likely to be harmed by the mercury in your tuna from what i can tell

http://www.mercurypolicy.org/new/documents/CanTheTunaReleaseFinal061903.pdf

 

Are they really saying, "Go ahead and throw them in your regular garbage?" What about the garbage men who are unknowingly and unprotected, handling these bulbs in yours and mine and everyones garbage? Can you imagine the amount of mercury vapor that will escape from the back of those trucks when they open the door to dump all those compacted (broken) bulbs? Will these guys become the next "Mad Hatters"? There's a class action suit waiting to happen!

 

BTW, How many 40/42ers does it take to change a light bulb?

 

Dan, I believe it is currently legal in almost, if not all, states to dispose of CFL's and batteries in public landfills for residential users. The Universal Waste rules are different for commercial applications.

 

Recently our church changed one of our rooms over and the answer to "How many Unitarian-Universalists does it take to change a light bulb? is "Too many"

 

Which brings us to this question: Why is it that the government warns pregnant women not to eat certain fish because mercury is harmful to their unborn babies, yet the government allows pharmaceutical companies to use mercury as a preservative in vaccines to be injected into infants and toddlers?

 

All garbage workers should wear protective clothing and gloves at all times, under the assumption that there may be hazardous waste in anybody's trash can. But I doubt that they actually take such precautions.

The EPA says to put discarded CFLs in 2 sealed plastic bags before putting them in the trash. We should at least observe that precaution for the sake of those who do our dirty work for very little pay and very little appreciation.

 

Probably about this many:

 

I believe that use has been changed, but I am not positive.

 

Not that much vapor compared to the background levels from all other uses. They would not be exposed to high enough concentrations for long enough to cause such a problem even in a worst case scenario.