SAFE HANDLING & DISPOSAL OF
|SAFE HANDLING & DISPOSAL OF
Additional Regulations Affect Demolition Industry: Pre-
Demolition Removal of Mercury-containing devices
from Residential and Commercial Facilities|
By MARK TIBBETTS
Thermostat Recycling Corporation
|Mercury can be found in various devices in
residential and commercial structures. If
not managed properly at the end-of-life,
these devices can break, releasing mercury into
the environment. Prior to demolition, facilities
should be inspected and these devices should be
removed to ensure proper disposal.
Mercury releases can present a serious
environmental and health problem. Inhaling
mercury vapors – which are colorless and
odorless – can cause irreversible damage to the
brain and kidneys. Even very small amounts of
mercury (less than a gram) may cause adverse
The central nervous system, eyes and
respiratory system can also be affected by mercury. Developing fetuses and children are the most sensitive to
mercury exposure. Inhalation of mercury vapor is the most harmful means of exposure. Mercury can also enter
the body through contact with the skin or by swallowing.
If released, mercury can pose a danger to people if not properly cleaned up and removed. It can easily
spread by walking (tracking), sweeping or vacuuming, thereby presenting a potential health threat to others.
Tracking throughout a building or into automobiles has spread mercury contamination to many other locations
in many instances.
Health impacts will increase over time if the mercury is not properly removed. Mercury vapors are heavier
than air and tend to remain near the floor or mercury source, but can get into the ventilation system and be
spread throughout a house or business. Indoors, mercury vapors will accumulate in the air. Children five
years of age and younger are considered to be particularly sensitive to the effects of mercury on the nervous
Mercury Seal Generator
|system since their central nervous system is
still developing. When pregnant women are
exposed to mercury, the mercury can pass from
the mother’s body to the developing fetus; it
can also be passed to a nursing infant through
CLEANING UP MERCURY SPILLS
If released, clean-up costs are significant. It
is not unusual for costs to range from $5,000
up to $300,000 for a single incident. Typical
response to mercury releases in homes has
consisted of relocating the residents and
providing temporary housing, gathering visible
mercury with a special vacuum, and heating
and ventilating the house to drive off the
harmful mercury vapors. In some instances,
walls, carpeting and floors of houses have
had to be removed because they were grossly
contaminated. Personal possessions have also
been discarded if they became contaminated
and the mercury could not be removed.
Contaminated materials are likely to be treated
as hazardous waste and sent to a special landfill
or a mercury retort facility. In a worst case
scenario mercury is spread from the original
release location into vehicles and other homes
via shoes or clothing; spreading contamination
and the scope of clean-up.
DEVICES THAT CONTAIN MERCURY
The three most common devices with significant amounts of mercury in them are mercury-switch thermostats,
gas pressure regulators, and mercury pressure switches.
Facilities that were built prior to 1968 may have a mercury-containing gas pressure regulator adjacent to
the gas meter. Most of these devices were manufactured and installed in the 1940s and 1950s. These devices
contain approximately two teaspoons of mercury. Mercury spills have sometimes occurred during improper
removal of these devices, causing a potentially significant health risk and resulting in costly cleanups.
Some older boiler heating systems have a mercury seal generator or mercury pressure switch(s). These
devices may be found near the boiler or near a radiator on an upper floor. They can contain up to several
fluid ounces of mercury. Mercury spills can occur as a result of improper removal of these devices. A spill can
require a significant cleanup effort. In April 2011, EPA responded to a mercury spill at a home where an old
1920s boiler had been improperly removed, resulting in a spill of about four fluid ounces of mercury.
The most commonly found mercury-containing devices are mercury-switch thermostats. While it its more
likely to find them in residential structures (single and multi-family), mercury-switch thermostats may also be
|found in commercial and light-industrial
facilities. Each thermostat contains up to
12 grams of elemental mercury and is
one of the largest remaining reservoirs
of mercury in residential buildings today.|
LEGAL ISSUES GOVERNING
The management of mercurycontaining
devices is regulated by both
state and federal authorities.
The Superfund Law (Section 104
of the Comprehensive Environmental
Response, Compensation, and Liability
Act (CERCLA) of 1980 as amended,
42 U.S.C. Sec. 9604) provides the US
Environmental Protection Agency (EPA)
the legal authority to respond to mercury
releases. The Superfund law also gives
EPA the authority to identify the party
responsible for the release, order those who improperly handle mercury to take appropriate response, and/or
compel them to pay for a cleanup.
Mercury Gas Regulator
(Courtesy of American Gas Association)
CERCLA also requires that any release amount above the quantity of one pound – one pound of mercury
is approximately two tablespoons – must be reported to the National Response Center.
The Emergency Planning and Community Right-to-Know Act requires that any release of mercury greater
than one pound be reported to the local emergency planning committee, state emergency response commission,
or local response personnel by the owner/operator.
Disposal of these devices may also be regulated by federal law.
Additionally, many states also regulate the disposal of mercury-containing products. Twelve states
specifically ban the disposal of mercury-containing products in solid waste. Additionally, some states, most
notably California and Illinois, require demolition contractors to remove and properly manage all mercurycontaining
thermostats prior to a building’s demolition.
Facilities need to be inspected, and if mercury is present, these devices need to be removed and disposed
of properly prior to a building’s demolition. In the instance of mercury-containing gas pressure regulators, the
removal needs to be coordinated with the gas utility.
In the case of mercury-switch thermostats, they can be managed as a universal waste, reducing costs
associated with transport and disposal. In fact, the manufacturers of mercury-switch thermostats established
a national program in which assumes all costs associated with the transport and disposal of whole
mercury-switch thermostats. For more information on the management of waste mercury thermostats visit