Laboratory Safety Manual
Reviewed May 2012
Chapter 1: Emergency Response
Section 1.1 - Chemical Spills
C. Mercury Handling and Spill Clean Up
1. Health Effects
The ACGIH has established a TLV of 0.05 mg/m3, based on an 8-hour day and 40-hour week. The
TLV for mercury also carries a "skin" notation, which indicates that metallic
mercury can be absorbed into the body as well as through inhalation and ingestion into the
skin. Mercury vapors are odorless, colorless, and tasteless. A quantity as small as 1
milliliter can evaporate over time and raise levels in excess of allowable limits. Mercury
poisoning from exposure by chronic inhalation can cause emotional disturbances,
unsteadiness, inflammation of the mouth and gums, general fatigue, memory loss, and
headaches. In most cases of exposure by chronic inhalation, the symptoms of poisoning
gradually disappear when the source of exposure is removed. Improvement, however, may be
slow and complete recovery may take years.
2. Storage and Handling
Because of the health effects of mercury, as well as the extremely difficult and time-consuming procedures
required to properly clean spills, every effort should be taken to prevent accidents
involving mercury. Always store mercury in unbreakable containers that are stored in a
well-ventilated area. When breakage of instruments or apparatus containing mercury is a
possibility, the equipment should be placed in an enameled or plastic tray or pan that can
be cleaned easily and is large enough to contain the mercury. Transfers of mercury from
one container to another should be carried out in a hood, over a tray or in a pan to confine
any spills. If at all possible, the use of mercury thermometers should be avoided. If a
mercury thermometer is required, many are now available with a Teflon coating that will
prevent shattering. Always wash hands after handling mercury to prevent skin absorption or
3. Air Monitoring
Any mercury spill has the potential to generate airborne concentrations in excess of regulated
levels. Contact EHS at 744-7241 for air monitoring of the spill area before cleanup to
determine the airborne concentration. Large spills or spills with elevated vapor levels
may dictate cleanup by a qualified contractor.
4. Protective Clothing
For small spills, a laboratory coat, safety glasses, and gloves should be used. Gloves made of
the following have been rated as excellent for protection against elemental mercury:
- Chlorinated polyethylene (CPE)
- Polyvinyl Chloride (PVC)
- Nitrile Rubber, (also known by several brand names)
- Viton® (Viton® is a registered trademark of DuPont Dow Elastomers)
- Butyl Rubber
If mercury has been spilled on the floor, the workers involved in cleanup and decontamination
should wear plastic shoe covers. EHS should be called immediately if a spill is extensive
enough to require workers to kneel or sit where mercury has been spilled since Tyvek or
similar impermeable clothing will be required
5. Mercury Spill Kits
Special spill kits are available from a variety of sources. If a spill kit is purchased, follow
the manufacturer's directions. Alternatively, a kit can be assembled with the following
6. Clean Up Procedures
- Wearing protective clothing, pools and droplets of metallic mercury can be pushed together and
then collected by a suction pump.
- After the gross contamination has been removed, sprinkler the entire area with zinc powder.
Spray the zinc with the dilute sulfuric acid.
- Using the sponge, work the zinc powder/sulfuric acid into a paste consistency while scrubbing
the contaminated surface and cracks or crevices.
- To minimize contamination of housekeeping items, stiff paper may be used to assist in
cleaning up the amalgam.
- After the paste has dried, it can be swept up and placed into the plastic container for
- Rags, shoe covers, sponges, and anything used for the cleanup should be placed in the trash bag
to be disposed of as contaminated material.
7. Waste Disposal
Emergency Response Radiation Spills