Mercury Spills

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 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!

Elemental mercury is somewhat volatile and is readily absorbed via the respiratory tract. Elemental mercury vaporizes slowly at room temperature but more quickly in a warm environment. Large volumes of mercury, mercury spilled inside heated equipment, and mercury spilled on fabric or carpet is very difficult to clean and poses increased risk of mercury inhalation. Small volumes of mercury (thermometer sized) are more easily managed with a low risk of mercury inhalation concerns.

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. Instructions for ordering a spill kit via eProcurement are on the ordering spill kits webpage. Because this spill kit is a special item for UW, it is not in the general catalog. This spill kit is also available at the Chemistry Stockroom and Biochemistry Stores and costs about $25. Please keep in mind that this spill kit can only be used only on small spills (less than 10 milliliters of mercury) on hard, nonporous surfaces.

Mercury spill kit
Large nitrile gloves
Ziploc bags 9"x13"
Cloth sponge
Syringe aspirators
Cloth sponge
500g Hg absorbent powder
Small scoop/scraper
Chemical Collection Request
Booklet of UW Hazardous Waste Labels

Small mercury spills on smooth 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.

14. Environmental Health and Safety provides mercury monitoring assistance if there are any concerns that mercury remains even after a cleanup. Call 206.543.7388 to request this service.

Large mercury spills or spills on porous surfaces

vacuuming mercury spill (19K)

In the case of large mercury spills, contact Environmental Health and Safety at 206.543.7388 prior to performing any cleanup actions. Mercury vapor monitoring must occur to determine of respiratory protection is required.

If respiratory protection is required, EH&S can arrange for spill contractor help. The spill contractor will use a mercury vacuum and a mercury absorbent material to clean surfaces and equipment.

If it is safe for the lab to conduct the cleanup, and they have access to a mercury vacuum, it is important that the lab package up the mercury correctly for EH&S hazardous waste collection.

For spill contractor help, or help managing mercury contaminated spill debris, call 206.543.0467.

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 procedure below:

1. Shut off the equipment, and if the equipment is small enough, place it in the fume hood. Then leave the area immediately.

2. Call EH&S at 206.543.0467 to report the spill and discuss cleanup. EH&S will arrange for mercury monitoring and, potentially, spill contractor help.

Mercury monitoring

Mercury monitoring must occur prior to cleanup actions when there is an increased risk of exposure, such as when large volumes of mercury have spilled (manometers and specialized instruments), spills in ovens or other heated equipment, and spills in hard to clean areas like carpet and upholstery.

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 206.543.7388 to initiate mercury monitoring in your workplace.