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Asbestos
Asbestos is a generic name given to a fibrous variety of
six naturally occurring minerals that have been used for decades
in the development of thousands of commercial products. The
term asbestos is not a mineralogical definition but a commercial
name given to a group of minerals that possess high tensile
strength, flexibility, resistance to chemical and thermal
degradation, and electrical resistance. Asbestos poses no
physical danger while bonded in products, it is when the products
that bond the asbestos fibers become damaged and release Asbestos
into the air that asbestos becomes a significant health hazard.
The six types of asbestos are chrysotile, crocidolite, amosite,
anthophyllite asbestos, tremolite asbestos, and actinolite
asbestos. Today, only one type of asbestos is used: chrysotile.
In addition, the industry now only markets dense and non-friable
materials in which the chrysotile fibre is encapsulated in
a matrix of either cement or resin. These modern products
include chrysotile-cement building materials, friction materials,
gaskets and certain plastics.
Asbestos Uses
Asbestos fibers are fireproof, and do not conduct heat or
electricity. Because asbestos does not conduct heat well and
is resistant to melting or burning, asbestos was used widely
in all types of construction products up to the mid-1970s.
Products made with asbestos, such as insulation and fireproofing
materials, automotive brakes and textile products, and cement
and wallboard materials, were designed principally to contain
heat and sound.
Workers at risk of asbestos exposure
An estimated 1.3 million employees in construction and general
industry face significant asbestos exposure on the job. Heaviest
exposures occur in the construction industry, particularly
during the removal of asbestos during renovation or demolition.
Employees are also likely to be exposed during the manufacture
of asbestos products (such as textiles, friction products,
insulation, and other building materials) and during automotive
brake and clutch repair work.
Asbestos Diseases
The asbestos minerals have a tendency to separate into microscopic-size
particles that can remain in the air and are easily inhaled.
Persons occupationally exposed to asbestos have developed
several types of life-threatening diseases, including lung
cancer. Although the use of asbestos and asbestos products
has dramatically decreased, they are still found in many residential
and commercial settings and continue to pose a health risk
to workers and others.
Asbestos workers have increased chances of getting two principal
types of cancer: cancer of the lung tissue itself and mesothelioma,
a cancer of the thin membrane that surrounds the lung and
other internal organs. These diseases do not develop immediately
following exposure to asbestos, but appear only after a number
of years.
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