Cleaning Up a Small Mercury Spill
Liquid mercury vaporizes (evaporates) at room temperature causing elevated levels of mercury in indoor air. Mercury vapor is not irritating and has no odor, so people do not know when they are breathing it. Even a tiny amount of mercury from a broken thermometer can cause harm, especially to children, unless it is cleaned up and removed.
Know where mercury may be found in your home
Mercury may be found in thermometers, thermostats, blood pressure units, barometers, and gas pressure regulators. Mercury exposure can occur when people handle or play with the liquid metal or when a measuring device breaks and mercury beads scatter onto floors or other surfaces. Spilled mercury is hard to clean up, especially if it rolls into cracks and crevices or is on fabric, upholstery, or other porous material.
Mercury health effects
- Breathing small amounts of mercury vapor can harm the nervous system of unborn babies, nursing infants, and children.
- Breathing larger amounts of mercury vapor can cause irritability, tremors, or memory loss; shortness of breath; respiratory & eye irritation; chest pain; high blood pressure; kidney damage.
What you should do immediately after a mercury spill.
Avoid contact with the spilled mercury until you decide who will clean it up – you or a professional. You can generally clean up a small mercury spill yourself, such as from a fever thermometer or thermostat. This fact sheet provides a step-by-step guide on pages 3-4 on how to do the cleanup.
it’s recommended that a trained professional, such as a hazardous waste contractor, do the cleanup whenever the amount of mercury spilled is greater than what is typically found in a fever thermometer or thermostat. In other words, if the amount of mercury spilled exceeds 3 grams, or about the size of a green pea, a trained professional should clean up.
Avoid spreading spilled mercury!
- Never use a vacuum cleaner, mop, or broom to clean up a mercury spill.
- Avoid walking through the spill area.
- Take children and pets to another room. Leave any clothing or footwear that came into contact with the spilled mercury in the affected room. If possible, close the room’s doors with the spilled mercury to keep vapors from spreading.
If the amount of mercury is more than what is in a thermometer – consider the following:
- Stay out of the room until you begin the cleanup. If you cannot clean the area immediately, cover the spill and surrounding area with plastic. You can use one or more trash bags, overlapping side by side, to cover the beads until you can clean the spill.
- Lower the room temperature, if possible, to reduce the evaporation of mercury.
- Shut down or close off vents that could spread mercury vapors to other areas.
- Open exterior windows to ventilate any mercury vapors to the outdoors. If possible, place a fan in a window to blow the vapors out but avoid breezes that might blow the mercury vapor back indoors or into other nearby residences. You can run a bathroom exhaust fan or a cooking stove hood, but only if it vents outdoors and only if it is located in the same room as the mercury spill.
Decide who will do the cleanup – you or a professional?
If the spill is… more than the amount in a mercury fever thermometer or thermostat, or if it is widely scattered, or if the spill is on the carpeting which cannot be thrown out, or on upholstered furniture, or other porous items that cannot be bagged… you should call a trained professional. Check your telephone Yellow Pages under “Hazardous waste,” “Engineering services,” or “Environmental engineers”.
If in doubt… contact your local health department or others listed at the end of this fact sheet for more information.
Plan if you have mercury-containing items in your home – get a Mercury Spill Kit
Mercury spill clean-up kits are available for purchase from laboratory equipment suppliers. Carefully follow all the directions provided in the kit. SEE ONE HERE
Mercury spill kits generally contain powders and suction devices. Additionally, it is recommended that you collect the items listed below and keep them with the kit.
List of what can be used to clean up a mercury spill:
- latex or vinyl gloves
- zipper-type plastic bags (several)
- plastic trash bags (at least two)
- wide tape (masking, duct, or clear)
- paper towels
- two index cards or pieces of stiff cardboard
- sulfur powder (see below for details)
- water to moisten paper towels
Sulfur powder (also called flowers of sulfur) can be purchased from agriculture supply stores, garden centers, and some pharmacies.
WARNING – NEVER use a vacuum cleaner, mop, or broom to clean up a mercury spill. The heat from the vacuum cleaner’s motor will increase the mercury vapor in the air. Mops and brooms will spread the mercury, making cleaning more difficult. The vacuum cleaner, mop, or broom will become contaminated with mercury.
NEVER use a washer or dryer to clean clothing contaminated with liquid mercury. The washer and dryer can become contaminated with mercury. If these items are contaminated with mercury, they are very difficult to clean and may have to be disposed of as hazardous waste.
Practical Information about mercury
A mercury spill usually forms several pools and many beads of mercury. Mercury does not stick to most materials other than some metals. Mercury beads roll very quickly, often scattering long distances from the original location of the spill and getting into cracks and crevices where it can be very difficult to remove them. Cleaning up a mercury spill requires patience and attention to detail to recover the mercury and limit your exposure to toxic mercury vapors.
Before you start to do a mercury spill cleanup!
You should have read the previous sections in this fact sheet that describe a small mercury spill, what you should do immediately after a mercury spill, and what you need to know if you decide to do the spill cleanup yourself. The following section is a general step–by–step guide on how to clean up a small mercury spill. You should complete the following steps to recover the spilled mercury and remove the contamination. Any mercury not removed will continue to be a source of potentially harmful mercury vapors.
Ten Steps for Cleaning Up a Small Mercury Spill
- Before cleanup, remove metal items like jewelry and watches since mercury can permanently damage them. Put on old clothes, old shoes, and latex or vinyl gloves. Put a clean change of clothes and shoes and a clean trash bag in a safe place outside the contaminated area. You will change out of your old clothes and shoes and put them in the trash bag at the end of the cleanup.
- Identify items in the spill area that can be cleaned and those that cannot. Non-porous surfaces (finished wood, plastic, or concrete) can be cleaned following this guidance. Porous surfaces or fabric-covered items (upholstery, carpeting, stuffed animals, pillows, backpacks, unfinished wood, cork, cardboard) are challenging to clean because mercury beads may be trapped in these materials. If you cannot clean these items, place them in plastic trash bags or cover or wrap them in a double layer of plastic and carefully seal them with tape. Place the wrapped items in a secure place, preferably outdoors and out of the reach of children and pets. You should consult a trained professional about safely decontaminating or disposing of these items.
- Wear gloves to carefully pick up the larger pieces of broken glass and what remains of the broken device and place them on a paper towel. Gently fold the paper towel around these pieces so you can pick the bundle up and place it in a zipper-type plastic bag. Use index cards or stiff cardboard to push smaller pieces of glass and mercury beads into a pile. Shine a flashlight at an angle to locate beads of mercury. The beads will reflect light from the flashlight. Check for mercury in cracks or hard-to-reach areas where beads may be hidden or trapped. Check a wide area beyond the spill.
- Use the eyedropper to collect mercury beads and place them in the plastic bag. Hold the eyedropper at an angle to draw the mercury into the tip. Keep the eyedropper at an angle to stop the mercury from rolling back out until you can put the mercury into the plastic bag. Wrap tape (sticky side out) around your gloved fingers and carefully use it to pick up any remaining glass or beads. Check again with the flashlight to ensure no mercury beads remain.
- At this point, mercury beads may still be trapped in cracks or crevices on irregular surfaces. Sprinkle sulfur powder over the contaminated area and rub it gently all over the surface and into the cracks with a paper towel. Sulfur powder binds with mercury. Use a paper towel dampened with water, followed by wiping with another damp paper towel to clean up the sulfur and mercury. Place the used paper towels in a zipper-type plastic bag.
- Put all the items used to pick up the mercury, including index cards or cardboard, eyedropper, contaminated tape, paper towels, and zipper-type bags, into the trash bag. Carefully remove rubber gloves by grabbing them at the wrist and pulling them inside out as they come off. Place the used gloves in the trash bag.
- Carefully seal the trash bag containing mercury-contaminated waste and put it in a secure place, preferably outdoors and out of reach of children and pets, until it can be disposed of safely.
- If possible, open a window and use a fan to ventilate the area to the outdoors for 24-48 hours before resuming normal use. If possible, heat the area (for example, with a space heater) while still ventilating to the outdoors. Avoid blowing the exhaust back indoors or into other nearby residences.
- Clothes or shoes that did not come in direct contact with liquid mercury should be removed and put into the trash bag that was left outside the contaminated area at the beginning of the cleanup. Close the trash bag and take it outdoors. Carefully remove the shoes and/or clothing from the trash bag and air them outdoors for 24 to 48 hours. After the outdoor airing, washable items can then be laundered.
- Dispose of contaminated items properly! Mercury-contaminated items should not be placed in regular household trash. Contact your town or county officials for information about hazardous waste disposal in your community.