What Is Asbestos and Why Is It So Useful?Asbestos is
a natural mineral with unusual qualities. It is strong enough
to resist high temperatures, chemical attack and wear. A poor
conductor, it insulates well against heat and
Asbestos crystals become long, flexible,
silky fibres, so it can be made into a wide variety of forms.
It can be spun into yarn, woven into cloth or braided into
rope. Asbestos can also be added to materials as diverse as
cotton and cement.
This combination of properties gives
asbestos performance capabilities that are difficult to match.
It has been called "the miracle mineral."
What Has Asbestos Been Used For?Asbestos has been
used in hundreds of applications and products over the past
4500 years. The ancient Greeks wove it into oil lamp wicks,
funeral shrouds and ceremonial tablecloths. During the 1800s,
it insulated the hot engines, boilers and piping that powered
the Industrial Revolution.
For half a century, until
the 1980s, asbestos was used in office buildings,
institutions, public buildings and schools. It insulated hot
water heating systems, and was put into walls and ceilings as
insulation against fire and sound.
Asbestos has also
been widely used in transportation and electrical appliances,
frequently mixed with, and encased in, other
Asbestos has also been found in many
products around the house. It has been used in clapboard;
shingles and felt for roofing; exterior siding; pipe and
boiler covering; compounds and cements, such as caulk, putty,
roof patching, furnace cement and driveway coating; wallboard;
textured and latex paints; acoustical ceiling tile and
plaster; vinyl floor tiles; appliance wiring; hair dryers;
irons and ironing board pads; flame-resistant aprons and
electric blankets; and clay pottery.
What Health Problems Are Associated With Exposure To
Asbestos?Asbestos poses health risks only when fibres are
present in the air that people breathe. When inhaled, asbestos
fibres lodge in the lungs, causing scarring that can
ultimately lead to severely impaired lung function
(asbestosis) and cancers of the lungs or lung
Concern for the health of asbestos workers was
expressed as long ago as the late 1800s. The risks became more
evident in the late 1960s, when workers who had been heavily
exposed 20 to 30 years earlier showed increased incidence of
lung disease. Occupational exposure is now strictly regulated
by provincial governments.
How Has the Use Of Asbestos Changed?When it became
evident that regular exposure to asbestos on the job involved
health risks, the public became more concerned about exposure
to asbestos in offices and schools, and, eventually, about all
asbestos products. This concern has led to a dramatic decline
in asbestos use since the early 1980s. The use of asbestos
insulation in buildings and heating systems has virtually
disappeared. Residential use, for roofing, flooring and
appliances, continues to decrease.
alternative products are being developed to replace asbestos,
it has not been banned altogether. It can be used safely, and
public concern has led to improved product design and
manufacture. Asbestos is now better encapsulated and sealed to
reduce the escape of fibres.
Asbestos is valuable in
many applications because it has been difficult to find
comparable substitute materials. For example, it is still an
important component of brake linings and clutch facings.
When Can Asbestos Be A Problem In the Home?Today, far
fewer products in the home contain asbestos. Current products
that do contain the material are better made to withstand wear
and use. However, frequent or prolonged exposure to asbestos
fibres may still bring health risks. This can happen with the
release of fibres into the air when asbestos containing
products break down, either through deterioration as they age
or when they are cut. People can put themselves at risk -
often without realizing it - if they do not take proper
precautions when they undertake repairs or renovations that
disturb asbestos-containing materials. This can occur in a
number of situations:
- Removal of deteriorating roofing shingles and siding
containing asbestos, or tampering with roofing felt that
- Ripping away old asbestos insulation from around a hot
- Sanding or scraping vinyl asbestos floor tiles
- Breaking apart acoustical ceiling tiles containing
- Sanding paint containing asbestos, or sanding or
disturbing acoustical plaster that gives ceilings and walls
a soft, textured look
- Sanding or scraping older water-based asbestos coatings
such as roofing compounds, spackling, sealants - or paint -
or putty, caulking or drywall
- Sawing, drilling or smoothing rough edges of new or old
How Is It Possible To Minimize the Risks Associated With
Asbestos In the Home?If you do not know whether products
in your home contain asbestos, you may wish to have an
experienced contractor inspect them. If the presence of
asbestos is confirmed, the best interim measure (unless the
product is peeling or deteriorating) is to seal the surface
temporarily so that fibres will not be released into indoor
air. If the product is already protected or isolated, simply
leave it alone.
It is a complex and expensive matter to
remove asbestos, and it is best done by an experienced
contractor. When disturbing an asbestos product, maximum
precautions must be taken to safeguard the workers and anybody
else who may be nearby. Asbestos dust must remain within the
work area so that it cannot be breathed in by unprotected
It is essential to take adequate precautions.
Everybody who works with asbestos should always wear an
approved face mask and gloves, along with protective clothing.
Be sure to tape sleeve and trouser cuffs, and wash clothes
separately after use. Keep the work area moist to keep dust
and fibre particles from floating into the air. Isolate the
work space. Reduce the air pressure to prevent asbestos fibres
from escaping from the work area, and filter the exhaust air.
Dispose of all waste appropriately, according to the
guidelines of your provincial Department of the Environment.
Other removal methods may be warranted for special conditions
- consult an expert.
Where Can You Get More Information On Asbestos?For
information on how to minimize exposure to asbestos and avoid
other risks while undertaking home renovations, obtain a copy
of the CMHC publication Avoiding Renovation Hazards, NHA 6560,
from your local CMHC office or the Canadian Housing
Information Centre, Canada Mortgage and Housing Corporation,
700 Montreal Road, Ottawa, Ontario K1A 0P7. Phone (613)
748-2367 Fax (613) 748-4069.
For information on
occupational exposure to asbestos, contact the Inquiries
Service, Canadian Centre for Occupational Health and Safety,
250 Main Street East, Hamilton, Ontario L8N 1H6,
1-800-263-8466 Fax (905) 572-4500.
For contractors who
specialize in asbestos abatement and removal, look in the
Yellow Pages under "Asbestos."