Before cleaning any mercury spills, be sure to read and
follow the precautions
found in the general mercury spill fact sheet.
Contain the Spill
Mercury will bead up and spread readily. If the further spread of
mercury beads is possible, place a barrier such as kitty litter, sand,
towels etc. around the spill site. If powdered sulfur or amalgamating
agent is available, use it to contain the spill. Pay close attention to
floor openings such as air vents and drains. Place barriers or tape around
the site to prevent traffic through it. Be sure to keep children and pets
Note: If the mercury was vacuumed, exposed to heat or entered the
ventilation system, refer to Large Spill
Guidance. Higher mercury vapor
levels may exist and could require additional protective equipment and
Evacuate the Spill Area
Before people leave the spill area, be sure they had not come into contact with
mercury. Avoid traffic going through the spill area. Those who may have
come into contact with mercury should be directed to a nearby location
away from the spill and asked to stay there until contamination can be
assessed and clean up completed. Once immediately outside of the spill
area, contaminated (direct contact with mercury) shoes and clothes should
be removed and double-bagged. Otherwise, mercury could be tracked around
the building or home.
Turn Off Ventilating or Air Conditioning Systems
If feasible, turn off heating, ventilation or air conditioning systems for the parts of the building affected by the spill and seal
the ventilation openings (both vents and returns).
Close Interior Doors to the Room
Close doors leading directly to the spill site and open exterior doors
and windows of the room where the spill occurred. When not occupied, seal
the door with plastic and tape.
Open Windows and Exhaust Room Air to the Outdoors
Place a fan in an exterior room window blowing air
Assemble Clean Up Supplies
Many clean up supplies are available from hardware stores. Mercury
spill kits area also available from suppliers (See the resource links
below). The following are some common household articles that could be
used to construct an in-home mercury cleanup kit:
- eye dropper- to pick up the
- plastic container with lid- to hold the mercury
- plastic sheeting- to provide a clean surface on which equipment can
- powdered zinc or sulfur*- to bind with the mercury
- rubber squeegee- to help recover the mercury and spill powder
- tape; wide, duct, or masking – to seal doors and vents and to help
pick up mercury beads
- tray or box- to hold mercury storage container
- plastic bags with zipper seal – to store mercury-contaminated
debris and equipment
- plastic dust pan- to help recover mercury and spill powder
- rubber gloves- to protect hands from mercury contact
- syringe without needle- to pick up mercury
- trash bags- for containing mercury waste
- playing cards or index cards- for collecting mercury beads
* zinc and sulfur will bind with mercury reducing the amount of
vapor. Sulfur will turn brown on contact with mercury.
Wear gloves (rubber), clothes and shoes that can be discarded if they
become contaminated. Wear safety goggles if available. Place Tyvek
booties, or use plastic bags as booties over shoes, to prevent your
shoes from being contaminated and allowing you to simply remove the bags
from your shoes upon leaving the room.
Pick Up All Visible Mercury Droplets
Inspect the spill area with a bright light to help illuminate any
hidden droplets. Clean up any beads of mercury by using a squeegee or
index card and plastic dustpan. With the card, gently push the mercury
droplets away from any carpet, fabric, or porous surfaces and toward
other droplets to combine them into larger droplets. Slide droplets onto
a sheet of rigid paper like an index card. Never use a broom on a
mercury spill because it will only scatter the mercury droplets, making
them harder to find and pick up.
Gently Place Mercury Into an Unbreakable Plastic Container
Use a plastic jar or double-bagged ziplock baggie, to deposit the
mercury into (avoid using glass because it can easily break). If
necessary, suction off the droplets using an eyedropper or syringe.
Adhesive tape strips may also be used to clean up any tiny remaining
mercury droplets. Place the plastic container inside a plastic bag to
provide additional safety. Tighten each lid securely so that liquid and
vapors will be contained.
Consider Removal and Disposal of Contaminated Carpeting or Other
Consider removal of carpet and other soft items that received direct
It takes very little mercury in air to create unhealthy levels of vapor.
Further, vacuuming any surface with mercury will make more vapor.
Factors that affect the severity of risk from mercury in carpet or
soft-surfaced items include the amount of mercury spilled, how much was
recovered, the type of room and whether young children or pregnant women
frequent the room. Local health departments and spill response
contractors may be able to monitor for the presence of mercury vapor on
contaminated items. However, private testing may be costly. The value of
the item should be weighed against such cost and the piece of mind
offered by the testing and/or removal of the contaminated item. When
removing contaminated items, double wrap them in plastic trash bags and
contact your local health department or Wisconsin Department of Natural
Resources below for proper
disposal. (Do not expose to heat or incinerate.)
Sprinkle Powdered Sulfur or Zinc on the Spill Site
Powdered sulfur or zinc will bind to any remaining mercury. These materials are supplied
in commercially available mercury spill kits (See spill kit sources
under Resources. Sulfur can often be purchased separately
from garden supply stores. Apply over hard to reach areas such as cracks
and crevices to minimize the release of mercury vapors. In instances
where furniture or carpet has been exposed to mercury, seek advice from
your local health department, the Department of Health
Services or a spill response contractor. Once
used to collect mercury, the powder must be disposed properly. Vapor
suppressing solutions are also available. See under Resources. (The use of powders on carpets is not
recommended, as later vacuuming will produce more mercury vapor).
Check Carefully for Missed Mercury
A very bright flashlight may be used to better illuminate mercury
beads in the spill area. Sprinkling powdered sulfur over the spill area
may also help identify missed mercury, as the powder will turn brown on
contact with mercury. Collect the powder as was done with mercury beads.
Special precautions should be taken if mercury was spilled in a high
traffic area or a confined area where children or infants play. Young
children playing on the floor are particularly at risk to mercury’s
effects on the central nervous system. Call the Department of Health Services, Bureau of Environmental Health at 608-266-1120 or your
department to see if additional testing or other measures may be needed.
Set Aside Everything You Think Might Be Contaminated With Mercury
Package materials securely and label as
"Mercury-Contaminated." Specific labeling and disposal
requirements may differ depending on whether the spill occurred at a
household or at a regulated business. Clothing or personal belongings
that may be contaminated can be tested following the guidance under Large Spills to see if they can be safely returned for use. Contact the disposal references
listed under Resources for assistance.
Monitor Spill Zone for Mercury Vapors
Even if the impacted area appears clean, there may still be
microscopic beads or hidden residual quantities of mercury present that
emit vapors. For larger-sized spills, it may be necessary to
professionally test mercury vapor levels in the immediate area. If
mercury is detected, re-clean the impacted area using previously
mentioned procedures and repeat testing until levels fall to within safe
parameters. If mercury vapor levels remain high even after repeated
cleaning, a more aggressive action is probably needed. Guidance for
acceptable levels for re-occupancy is offered below. Contact the
Department of Health Services, Bureau of Environmental Health
at 608-266-1120 or the
contractors under Resources for assistance.
Ventilate as much as possible to completely air out the room or spill
zone with outside air.
Airborne Exposure Levels
Units of measure are very important in evaluating mercury spills.
Airborne levels are reported in weight per cubic meter of air (m3).
Weight can be expressed as milligrams (abbreviated as mg, a thousandth
of a gram), microgram (abbreviated as ug, a millionth of a gram) or
nanograms (abbreviated as ng, a billionth of a gram).
Reference Concentrations for Airborne Mercury Exposure
Exposure Value (micrograms
per cubic meter)
Immediately Dangerous to Life or Health (IDLH) value allowable
for a maximum of 30 minutes in emergency situations only
Occupational Safety and Health Administration (OSHA)
Enforceable workplace standard, assuming 8 hours/day, 40
National Institute of Occupational Safety and Health (NIOSH)
Agency for Toxic Substances and Disease Registry (ATSDR)
Level at which residents are advised to not occupy the affected
area. Also a screening level for bagged clothes
Target cleanup level for commercial environments
Target cleanup level for residential environments
Chronic level of exposure at which adverse effects would not be
expected. Assumes exposure time of 24 hours/day for 30 years
Typical background level
Inventory All Remaining Mercury-Containing Devices and Replace Them
With Mercury-Free Alternatives
The best way to address a mercury spill is to prevent it from ever
happening in the first place. For assistance with reducing mercury use
contact the Wisconsin Department of Natural Resources at 608-267-7639.
If significant exposure is believed to have occurred, you should
discuss with your family doctor whether urine mercury tests should
be conducted for the people who use the area the most. Results should not
be above 20 micrograms per liter of urine (20ug/L).
to Mercury Spill Response Home
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August 12, 2014