Look for mercury in goods and products
Mercury can be found in any number of technical components and
products, which in turn can be found in various types of industrial and
home environments. Here are a number of useful hints as to where and how
you can look for mercury and how you should handle such products when you
come across them.
Which products can contain mercury?
The fact that we still use mercury is because most products containing
mercury have a long life, sometimes more than 40 years. Mercury’s
conductivity, high density and linear expansion with heat has been
utilised in many areas, for example in electrical switches, pressure
gauges and thermometers.
The list of technical components that could contain mercury is
therefore long. Here are some examples:
- Barometers and manometers
- Flow meters
- Strip lights and other light sources
- Sender level switches
- Pressure switches
- Circuit breakers
- Time switches/landing switches
The above mentioned components can in turn be found in many different
types of instruments, apparatus and other products, for example
- Battery chargers
- Cars (automatic lights and collision sensors)
- Central clocks and time clocks
- Dishwashers (electrical switches)
- Freezers (automatic lights)
- Lifts for disabled
- Measuring and control instruments
- Float switches and level meters
- Door bells ("ding-dong")
- Skylifts (levelling)
- Bedside lamps with automatic lights, e.g. for hospitals
- Signal alarms
- Transformers (gas-operated relays)
Note that mercury can be enclosed and hidden from the eye even after
removing covers and casings on products containing the substance, for
example in thermometers and thermostats with capillary tubes.
In which environments can mercury be found?Many
years of frequent use mercury-containing components means that the
substance can be found in all types properties and industries as well
fixedportable mobile equipment. Here are some examples places where
equipment containing mercury often found.
Distributions boxes and electric installations
is often found in relays located in distribution boxes in buildings, e.g.
for regulating stair lights.
Small boiler rooms often contain tube
thermometers and other thermometers. Oil level gauges for remote
measurements are also common.
District heating plants and furnace rooms
housing estates and industrial areas often have a central heating plant
with flue-gas meters, tube thermometers, thermostats, pressure switches,
oil level gauges, flow meters, etc.
Here you can find manometers,
thermostats, thermometers, relays, etc. containing mercury.
Sumps and tanks
In low-lying areas in buildings, for
example, you may find pumping equipment regulating the water level with
sender level switches that can contain mercury. Tanks and cisterns can
also have switches containing mercury.
Within industry there are all
possible types of mercury products installed in distribution boxes,
electrical surrounding equipment, boiler rooms, sumps, machinery,
measuring instruments, etc.
Machinery and equipment
A number of types of machinery
and equipment can contain mercury, e.g. level indicators in skylifts and
mobile ladders, industrial welding equipment, forestry machinery,
gas-operated relays in transformers, manufacturing machinery, etc.
In laboratories and schools mercury has
been used as a reagent for different analyses, as well as in thermometers
and other measuring instruments.
Drains and old waste pipes
In dental surgeries and other
premises where mercury is used, amalgam and metallic mercury can have
collected in waste pipes, leaching mercury into the sewerage.
Printed circuit cards in electrical
components in machinery and equipment can contain mercury. Companies
specialising in dismantling electronic equipment will handle this in an
environmentally safe way.
Checklist: Dispose of mercury in a safe
Property owners, companies, other enterprise and households have a
responsibility to help locate the "hidden mercury stores" and to dispose
of them in a safe way to avoid spreading mercury environment. The
checklist below can be used as an aid for inventory and disposal of
mercury in an environmentally sound way.
According to the "rules of consideration" in Swedish legislation,
persons carrying out an operation must avoid the use of hazardous
chemicals that can damage people’s health and the environment. Therefore,
alternatives to products containing mercury should be used wherever
possible. The rules require knowledge among personnel about substances
that are handled.
Ensure that handling follows routines which met the requirements for
good a working environment and natural environment, all the way from
inventory to disposal.
1. Take stock
Find out where there are components that may
contain mercury. Looking for mercury contained in products is practical
work, often requiring some form of electrical knowledge. In some
environments, only authorised persons are admitted. The inventory often
requires dismantling of lids and casings in order to find the mercury.
Also check stockrooms and old stores.
2. Dismantle and replace
Remove all mercury-added products
that can be dispensed with. Be careful as not to break the products when
dismantling. All components that are or have been in contact with mercury
are hazardous waste.
Dismantled components should be stored safely. One litre of mercury
weighs around 13.6 kg, so even small amounts can pose a strain on
receptacles and other containers. If in doubt, contact someone with
professional experience, e.g. your local refuse disposal.
3. Label and document
If a mercury-containing product in use
cannot be replaced: Label the product clearly so that it is obvious that
it contains mercury. Make a list over all products containing mercury and
where they are found, so that they do not disappear by mistake or through
ignorance when being replaced or in case of rebuilding or demolition. Keep
the list safe with the person responsible for the operation.
4. Collect and hand in
Metallic mercury and
mercury-containing products that are being disposed with constitute
hazardous waste and should be separated from other waste. Handle mercury
waste carefully, so that mercury from broken thermometers, glass phials,
etc. does not leak out. Label the wrapping carefully as to its contents so
that it is not lost or mixed up with other waste.
Prohibited use of certain products containing
The Ordinance on Prohibition in Connection with Handling, Importation
and Exportation of Chemical Products Etc. (Certain Cases), §§9-11 (SFS
1998:944) prohibits the manufacturing and sale of the following
mercury-containing measuring and control instruments, electrical goods and
- Clinical thermometers and other thermometers containing mercury.
- Float switches, pressure switches, thermostats, relays, electrical
contact breakers and contacts for continuous current transmission.
- Measuring instruments other than above.
Products of this kind taken into use before 1 January 1995 that have
been in use since then are exempt from the ban. However, it is not
permitted to reinstall components that have been taken out of operation.
There is therefore no need to keep mercury-containing components and
equipment in stock.
According to the same Ordinance (§8), Sweden introduced a prohibition
on the export of mercury on 1 July 1997.
- Mercury and mercury-containing chemical compounds and preparations
may not be commercially exported.
Contact: Kristina von Rein
Swedish Environmental Protection Agency