We perform air monitoring and visual examinations for pre-existing mercury spills, leaks, and
contamination. We also respond to mercury spills and help building owner prepare plans and
a scope of work (mercury remediation plan) for contractors to follow.
Generally, mercury spills or leaks occur from a few different sources. Thermostats, gauges, thermometers, meters, and
switches contain several grams of mercury in fragile glass bulbs or ampoules.  These ampoules (as well as mercury
containing thermometers) may break, releasing droplets of toxic mercury. Fluorescent lamps, including energy saving
compact fluorescents, contain mercury.  When a lamp breaks, it releases mercury into the air.

Handling of small spills (< 1 pound or 2 Tablespoons)

The Massachusetts DEP has developed a set of procedures that is suggested as a guide to be used if small spills (< 1
lb.) of elemental (liquid) mercury is spilled on a hard surface (e.g., concrete, vinyl or ceramic tiled floors). No re-
occupancy cleanup levels via mercury vapor screening or ambient air monitoring are included.

Handling of large spills (over 1 pound or 2 Tablespoons)

  • Immediately evacuate everyone from the room and close the doors.  Turn off central heating or cooling system.

  • Call FTL at 413-221-8233 and DEP’s emergency response hotline at 617-556-1133 or 888-304-1133 (24 hours)
    to report the spill.  DEP personnel will advise you how to clean up the spill or call for assistance, based on your

  • If the spill involves one pound of mercury (about two tablespoons) or more, responsible persons must report the
    spill to the MassDEP within two hours from the time when they became aware of the release.


Currently, no Massachusetts regulations exist that regulate cleanup procedures, training, indoor air quality limits, or re-
occupancy cleanup levels following a low-level mercury-release cleanup in residential, commercial, or educational

The Illinois Department of Public Health (IDPH), the U.S. Environmental Protection Agency (USEPA), Region 5, and
the Agency for Toxic Substances and Disease Registry (ATSDR) worked together to respond to the problem of
elemental mercury contamination in residential homes in northern Illinois. In this health consultation report, ATSDR
and IDPH established a cleanup clearance level of 1 microgram per cubic meter of air (ug/m) (equivalent to 1,000
ng/m3 or 0.001 mg/m3), and a relocation action level of 10 ug/m (equivalent to 10,000 ng/m3).

Instantaneous, direct-read screening for mercury vapors is conducted utilizing a Lumex RA-915+ Mercury Analyzer,
calibrated with standard units traceable to NIST.  Mercury vapor concentrations of ambient air are recorded by reading
the LCD display in nanograms per cubic meter (ng/m3) in On-Stream survey mode over a period of every 20 seconds,
with a Detection Limit of 2 ng/m3 of mercury, at a flow rate of 20 liters per minute (lpm). Readings are capable of
being maintained accurately between samples without baseline drift +/- 20%.

Our Industrial Hygienist can perform mercury vapor screening before, during, and after the remediation work (post-
remediation or “re-occupancy”). Re-occupancy screening can be performed only after a final visual inspection of the
remediation work reveals a condition of no visible liquid mercury droplets at the points of release/deposit and cleaned
areas. Post-remediation screening results can be compared to: 1) the ATSDR Occupational/Commercial Re-occupancy
level of 3.0 μg/m3 (3,000 ng/m3), 2) the OSHA Ceiling Limit (PEL) of 0.1 mg/m3 (100,000 ng/m3), and 3) the
Massachusetts Department of Environmental Protection reportable concentration for surface soil of 164 mg/m3
(164,000,000 ng/m3).
Asbestos Consulting & Testing

Indoor Air Quality Investigations

Mold Investigations

Lead Paint Sampling

PCB Testing & Consulting

Industrial Hygiene Services

OSHA Health & Safety Training

Mercury Screening & Spill Cleanup
Forbes & Wheeler
Serving Connecticut, Massachusetts, Rhode Island, New Hampshire, Vermont