Elemental mercury
Elemental mercury spills account for about 40% of the spills that UW EH&S receives calls for.
Thermometers, manometers, blood pressure cuffs, and many other instruments contain elemental mercury and are easily broken. In addition, small amounts of elemental mercury are in UV lamps and fluorescent lamps.
Mercury affects the central nervous system and with prolonged exposure can cause brain damage and worse. Mercury is the reason we have the term "mad as a hatter" - top hats used to be made with fur "felted" in an open elementary mercury bath.
Elemental mercury is somewhat volatile and is readily absorbed via the respiratory tract and through skin. Mercury spilled on fabric or carpet is also very difficult to clean and poses increased long term risk of mercury inhalation.
Mercury spill kits
If you have mercury containing items in your laboratory, you must also have a mercury spill kit. Custom UW mercury spill kits are sold by VWR via eProcurement (part #TXMERCURYSPILL). This spill kit is also available at the Chemistry Stockroom and Biochemistry Stores. Please keep in mind that this spill kit only can be used only on small spills (less than 10 milliliters of mercury) on hard, nonporous surfaces.
If you have spilled a small amount of mercury on a smooth surface, follow these directions carefully:
1. If your small mercury spill is on a porous surface, such as carpet, upholstery or concrete, manage it as if it were a large mercury spill (see below.)
2. Mark or tape off the spill to prevent others from walking through or touching the spill.
3. Wear two pairs of chemical resistant gloves (nitrile and/or Silver Shield), a lab coat and eye protection.
4. Using a scraper, push scattered mercury droplets together into a larger droplet. Turn off the lights and use a flashlight to see small mercury droplets.
5. Aspirate the larger mercury droplets with the syringe aspirator and place them into a Ziploc bag or screw top container.
6. Sprinkle mercury absorbent powder lightly over area to absorb the smallest mercury droplets.
7. Spray a water mist over the powder.
8. Using the scraper, mix the materials into a paste.
9. Scoop up the paste and wipe down the surfaces with a scraper and damp sponge.
10. Place the amalgam, sponge, gloves, scraper, scoop, and all other mercury contaminated debris into the Ziploc bag or container.
11. Tape the sharp ends of the glass thermometer and place it into the bag or container.
12. Label the bag or container with a UW hazardous waste label. Identify the waste as "mercury thermometer spill debris, 100%".
13. Complete a Chemical Collection Request and fax it to 206.685.2915.
Large mercury spills or spills on porous surfaces
Instead of using the syringe aspirator as above in step 5, use a mercury vacuum to minimize your exposure to mercury vapors. A photograph of a mercury vacuum is shown at right. Call the EH&S Spills Hotline at 206.543.0467 as soon as possible for a mercury vacuum.
When you have finished vacuuming, continue with step 6 above.
In some instances porous surfaces such as carpets and upholstery cannot be completely decontaminated and are disposed of as hazardous waste. Contact EH&S for mercury monitoring after your cleanup.
Heated mercury spills
When the spill occurs in heated equipment such as an oven or incubator, an exposure to mercury vapor is more likely. In these cases, follow the below procedure:
1. Shut off the equipment and leave the area immediately.
2. Call EH&S at 206.543.7388 to initiate monitoring of mercury concentrations in the area, which is required before cleanup. We will let you know if and when you can clean up the mercury spill.
Mercury monitoring
Post clean-up monitoring must also be conducted by EH&S after all mercury spills, no matter the size. We measure the mercury vapor concentrations in your workplace to ensure that the clean up was thorough. Even trace amounts of mercury left behind can cause unhealthful and illegal ambient mercury concentrations in your workplace. If you've not already contacted EH&S about your mercury spill, call 206.543.0467 or email chmwaste@u.washington.edu to initiate mercury monitoring in your workplace.
UW Medical Center mercury spills
UWMC clinical employees should contact UWMC Environmental Services at 206.548.6181 for assistance with mercury spills. The UWMC has a mercury vacuum for spills in clinical areas.
Free thermometers!
Mercury thermometers should be replaced with alcohol thermometers. We'll collect your old thermometers and other equipment and leave you a new alcohol thermometer.
Click here for a FREE thermometer!
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