Asbestos is a name given to a group of minerals which occur naturally as
masses of long silky fibres. Asbestos is known for its unique properties
of being resistant to abrasion, inert to acid and alkaline solutions, and
stable at high temperatures. Because of these attributes, asbestos was widely
used in construction and industry. Asbestos fibres are woven together or
incorporated within other materials to create many products.
three main types of asbestos fibres:
silky, flexible white fibres (the most commonly used asbestos in the United
States and Canada). Current evidence suggests that Chrysotile may be less
hazardous than Amosite or Crocidolite, although still considered a carcinogen.
Straight, brittle fibres that are light grey to pale brown (the most commonly
used in thermal system insulation).
Straight blue fibres.
three other types of asbestos fibres: Anthopylite, Tremolite, and Actinolite,
which are found as contaminants in Asbestos Containing Materials (ACM).
Asbestos has been mined and used commercially in North America since 1880,
but its use increased greatly during and after World War II. The building
and construction industry used asbestos for strengthening cement and plastics.
Asbestos was also used for heat insulation, fire proofing, and sound absorption.
Because of its good friction and wear characteristics, asbestos is often
used in brake shoes and clutch pads in cars, trucks, and airplanes.
CAN ASBESTOS BE FOUND ON CAMPUS?
Asbestos containing materials can be classified into one of three types:
Sprayed or trowelled-on material, Thermal System Insulation, or Miscellaneous
or trowelled-on materials used on ceilings or walls:
This surfacing material is found as a white, popcorn textured decorative,
acoustical, and fire proofing cover in homes, buildings, and schools.
2- Thermal System Insulation:
Here asbestos is often found as plaster cement wrap around boilers, on
water and steam pipe elbows, tees, fittings, and pipe runs. Asbestos is
also found on duct systems, and as a cardboard type of material (called
aircell) found on steam pipe runs.
3- Miscellaneous material:
This includes all materials containing asbestos which were not included
in the above groups. For example: floor tile, sheet rock, ceiling tiles,
automotive friction products, rubber tile matting, rubber stair treading
and risers, auditorium acoustical panels and sound proofing, gasket material,
stage curtains, roofing materials, transite siding, caulking, cement pipe,
kiln insulation, electrical panel insulation and wiring, fire brick, tar,
types of ACM are found on campus since many of the University structures
were built prior to the time that government controls were placed on the
use of asbestos in construction materials. The University has procedures
in place to protect employees, students, and the public from exposure
PEOPLE EXPOSED TO ASBESTOS ?
People are exposed to asbestos by the inhalation of asbestos fibres. Asbestos
Containing Materials (ACM's) which can be crumbled, pulverized, or reduced
to powder by hand pressure are known as friable asbestos. When friable
ACM is damaged or disturbed it releases fibres into the air. Airborne
asbestos fibres are small, odorless, and tasteless. They range in size
from 0.1 to 10 microns in length (a human hair is about 50 microns in
diameter). Because asbestos fibres are small and light, they can be suspended
in the air for long periods. People who come in contact with friable asbestos
are at risk of inhaling fibres. People who live or work near asbestos
related operations may also inhale asbestos fibres that have been released
into the air by work activities.
As long as
ACM's remain undisturbed and asbestos fibres are not released into the
air, there is no hazard to people coming in contact with the materials.
THE AMOUNT OF EXPOSURE TO ASBESTOS?
The amount of asbestos a person is exposed to will vary according to several
1- the fibre concentration in the air;
2- the duration of exposure;
3- the worker's breathing rate;
4- the environmental conditions; and
5- whether or not personal protective equipment is worn.
has been so widely used in North America that the entire population has
been exposed to some degree. Air, beverages, drinking water, food, drugs,
dental preparations, and a variety of consumer products all may contain
small amounts of asbestos. In addition, asbestos fibres may be released
into the environment from outcrops of bedrock in the earth. The asbestos
containing rocks release fibres as a result of wind, water and chemical
THE OCCUPATIONAL EXPOSURE LIMIT FOR ASBESTOS?
Asbestos is identified as a designated material by the provincial Workplace
Health Hazard Regulation and therefore is automatically declared as posing
a potential health hazard. The Workplace Health Hazard Regulation (MR
53/88) defines the occupational exposure limit of a designated material
as the level as close to zero as is reasonably practicable, but shall
not exceed the Threshold Limit Value established by the American Conference
of Governmental Industrial Hygienists. Workplace Safety and Health recognizes
the level as close to zero as is reasonably practicable for all forms
of asbestos as 0.1 fibres per cubic centimetre of air.
WHAT ARE THE EFFECTS OF EXPOSURE TO ASBESTOS ?
Once inhaled, the small, inert asbestos fibers enter the lungs. They are
deposited and retained in the airways and tissues of the lungs. In the
alveoli, the location of gas exchange, asbestos causes the development
of scar tissue. This thickening of the alveoli wall reduces the amount
of oxygen available to the body. Because asbestos fibers remain in the
body for a prolonged period of time, each exposure increases the likelihood
of developing one or more of the following diseases. All of these conditions
only become apparent many years after the start of exposure.
A chronic lung ailment caused by the build up of scar tissue inside the
lungs. Asbestosis can cause shortness of breath, permanent lung damage,
and increases the risk of lung infections. The development of asbestosis
requires significant prolonged exposure to high concentrations of asbestos
fibers and is rarely seen.
2- Asbestos related pleural fibrosis:
A thickening in the lining of the lungs. This is the most common effect
of asbestos seen today and usually causes no symptoms. This condition
is not cancer, but is a marker of significant asbestos exposure.
3- Lung cancer.
A rare form of cancer of the chest cavity lining or abdominal cavity.
5- Other cancers:
There is evidence to suggest that cancers at some other sites, primarily
gastrointestinal, may be associated with asbestos exposure.
is so ubiquitous we are all exposed to it in minute quantities. However,
to develop disease one must have substantial exposure to friable asbestos.
Usually, such exposure requires working with the friable product over
a long period of time. Generally, asbestos respiratory diseases take two
or more decades to develop from the time of exposure, and then only after
extensive and long term exposure to friable asbestos. The more extensive
and longer the exposure, the more risk an individual has for developing
have shown the combination of smoking and asbestos exposure to be particularly
hazardous. Cigarette smokers exposed to high concentrations of asbestos,
are on the average fifty times more likely to develop lung cancer than
non-smokers who are not exposed to asbestos.
BE TESTED' FOR ASBESTOS?
Workers who have had significant exposure to asbestos, should document
this exposure. There is no specific test to measure asbestos in the body.
Medical surveillance programs have been developed to try to identify whether
workers show any effects of asbestos exposure. These programs involve
taking a work history and a chest radiograph and lung function test. The
University is in the process of developing a surveillance program for
its staff who may have had higher exposures to asbestos for long periods
of time. The details of this program will be provided at a later date.
ARE IN PLACE FOR DEALING WITH ASBESTOS AT THE UNIVERSITY ?
The University recognizes its responsibility to ensure the safety and
health of all employees who may work in the vicinity of, or who may remove,
asbestos-containing materials (ACM) as part of their job duties. The University
also recognizes that every effort must be made to minimize the exposure
of building occupants and maintenance and custodial staff to airborne
asbestos fibres. The University has taken the following steps:
The University has adopted the Workplace Safety and Health Guideline "Guidelines
for Working With Asbestos" and all work procedures must conform to
this standard. Training of University staff and others who may come in
contact, or work with ACM, will continue to be conducted and evaluated.
The survey, inventory and periodic reassessment of all suspect and ACM
will continue to be conducted. The University has an on-going program
to audit University buildings to determine where ACM exist in the buildings.
When repairs and maintenance work are undertaken in these buildings, proper
precautions and procedures are taken to ensure there is no exposure to
workers and others who may be affected by the work. Where maintenance
work is conducted in buildings that have not yet been audited, bulk samples
of potential ACM will be taken and sent to an accredited lab for analysis.
If ACM is found and the material may become disturbed and friable due
to the procedures, proper work protocols will be followed.
The University has developed work practices and procedures that will allow
renovation, construction or emergency maintenance to be performed safely
without exposing employees, building occupants, or members of the public
to airborne asbestos fibres. When major building modifications, additions,
etc. are planned, comprehensive asbestos audits are undertaken prior to
the work to determine the location of asbestos. If ACM is found, it will
normally be removed by an asbestos abatement contractor prior to the construction
The University has an asbestos air monitoring program in place to determine
if there is any asbestos exposures above the recognized provincial standard.
Testing is conducted both in-house and by external asbestos consultants
to ensure that there are no risks to staff and students from exposure
to ACM's. At no time has the University found air monitoring results above
the provincial occupational exposure limits.
The University is in the process of consolidating all the elements already
in place into a documented and comprehensive Asbestos Management Program,
in cooperation with an external asbestos management consultant. The development
of the AMP will include the participation of all interested members of
the campus community.
YOU DO IF YOU HAVE CONCERNS ABOUT ASBESTOS?
Should you have concerns regarding any potential exposure to asbestos,
please discuss this with your supervisor or Department Head. The Environmental
Health and Safety Office (EHSO) may be contacted at: 474-6633 at any time
for assistance and advice on this issue.