What is Asbestos?
Asbestos is the name applied to six naturally occurring minerals that are mined from the
earth. The different types of asbestos are:
Of these six, three are used more commonly. Chrysotile (white) is the most common, but
it is not unusual to encounter Amosite (brown / off-white), or Crocidolite (blue) as well.
All types of asbestos tend to break into very tiny fibers. These
individual fibers are so small that many must be identified using a
microscope. In fact, some individual fibers may be up to 700 times
smaller than a human hair. Because asbestos fibers are so small,
once released into the air, they may stay suspended there for hours
or even days.
Asbestos fibers are also virtually indestructible. They are resistant to chemicals and heat,
and they are very stable in the environment. They do not evaporate into air or dissolve in
water, and they are not broken down over time. Asbestos is probably the best insulator
known to man. Because asbestos has so many useful properties, it has been used in over
3,000 different products.
Usually asbestos is mixed with other materials to actually form the products. Floor tiles,
for example, may contain only a small percentage of asbestos. Depending on what the
product is, the amount of asbestos in asbestos containing materials (ACM) may vary from
Where is Asbestos Found?
Asbestos may be found in many different products and many different places. Examples
of products that might contain asbestos are:
Sprayed on fire proofing and insulation in buildings
Insulation for pipes and boilers
Wall and ceiling insulation
Putties, caulks, and cements (such as in chemical carrying cement pipes)
Siding shingles on old residential buildings
Wall and ceiling texture in older buildings and homes
Joint compound in older buildings and homes
Brake linings and clutch pads
At OSU, asbestos is most likely to be found in:
Sprayed on insulation in locations such as various mechanical rooms, steel
reinforcing beams, and some ceilings in older buildings
Ceiling tiles in buildings built prior to 1981
Most 9" floor tiles in buildings built prior to 1981
A few 12" floor tiles in buildings built prior to 1981
Insulation around pipes and boilers, and
Interiors of fire doors
Buildings that have asbestos-containing materials in them will have notices posted near
the main entrances, frequently near the fire alarm panel.
Pipe and boiler insulation that contains asbestos will be labeled with identifying stickers
Asbestos-containing ceiling tiles will not be labeled or marked. These tiles cannot be
differentiated from other tile by visual means - they must be analyzed by a laboratory
When is Asbestos Dangerous?
The most common way for asbestos fibers to enter the body is through breathing. In fact,
asbestos containing material is not generally considered to be harmful unless it is
releasing dust or fibers into the air where they can be inhaled or ingested. Many of the
fibers will become trapped in the mucous membranes of the nose and throat where they
can then be removed, but some may pass deep into the lungs, or, if swallowed, into the
digestive tract. Once they are trapped in the body, the fibers can cause health problems.
Asbestos is most hazardous when it is friable. The term "friable" means that the asbestos
is easily crumbled by hand, releasing fibers into the air. Sprayed on asbestos insulation is
highly friable. Asbestos floor tile is not.
Asbestos-containing ceiling tiles, floor tiles, undamaged laboratory cabinet tops, shingles,
fire doors, siding shingles, etc. will not release asbestos fibers unless they are disturbed
or damaged in some way. If an asbestos ceiling tile is drilled or broken, for example, it
may release fibers into the air. If it is left alone and not disturbed, it will not.
Asbestos pipe and boiler insulation does not present a
hazard unless the protective canvas covering is cut or
damaged in such a way that the asbestos underneath is
actually exposed to the air.
Damage and deterioration will increase the friability of asbestos-containing materials.
Water damage, continual vibration, aging, and physical impact such as drilling, grinding,
buffing, cutting, sawing, or striking can break the materials down making fiber release
Because it is so hard to destroy asbestos fibers, the body cannot break them down or
remove them once they are lodged in lung or body tissues. They remain in place where
they can cause disease.
There are three primary diseases associated with asbestos exposure:
Asbestosis is a serious, chronic, non-cancerous respiratory disease. Inhaled asbestos
fibers aggravate lung tissues, which causes them to scar. Symptoms of asbestosis include
shortness of breath and a dry crackling sound in the lungs while inhaling. In its advanced
stages, the disease may cause cardiac failure.
There is no effective treatment for asbestosis; the disease is usually disabling or fatal. The
risk of asbestosis is minimal for those who do not work with asbestos; the disease is
rarely caused by neighborhood or family exposure. Those who renovate or demolish
buildings that contain asbestos may be at significant risk, depending on the nature of the
exposure and precautions taken.
Lung cancer causes the largest number of deaths related to asbestos exposure. The
incidence of lung cancer in people who are directly involved in the mining, milling,
manufacturing and use of asbestos and its products is much higher than in the general
population. The most common symptoms of lung cancer are coughing and a change in
breathing. Other symptoms include shortness of breath, persistent chest pains, hoarseness,
People who have been exposed to asbestos and are also exposed to some other carcinogen
-- such as cigarette smoke -- have a significantly greater risk of developing lung cancer
than people who have only been exposed to asbestos. One study found that asbestos
workers who smoke are about 90 times more likely to develop lung cancer than people
who neither smoke nor have been exposed to asbestos.
Mesothelioma is a rare form of cancer which most often occurs in the thin membrane
lining of the lungs, chest, abdomen, and (rarely) heart. About 200 cases are diagnosed
each year in the United States. Virtually all cases of mesothelioma are linked with
asbestos exposure. Approximately 2 percent of all miners and textile workers who work
with asbestos, and 10 percent of all workers who were involved in the manufacture of
asbestos-containing gas masks, contract mesothelioma.
People who work in asbestos mines, asbestos mills and factories, and shipyards that use
asbestos, as well as people who manufacture and install asbestos insulation, have an
increased risk of mesothelioma. So do people who live with asbestos workers, near
asbestos mining areas, near asbestos product factories or near shipyards where use of
asbestos has produced large quantities of airborne asbestos fibers.
Evidence suggests that cancers in the esophagus, larynx, oral cavity, stomach, colon and
kidney may be caused by ingesting asbestos. For more information on asbestos-related
cancers, contact your local chapter of the American Cancer Society.
Three things seem to determine your likelihood of developing one of these asbestos
1. The amount and duration of exposure - the more you are exposed to asbestos
and the more fibers that enter your body, the more likely you are to develop
asbestos related problems. While there is no "safe level" of asbestos exposure,
people who are exposed more frequently over a long period of time are more at
2. Whether or not you smoke - if you smoke and you have been exposed to
asbestos, you are far more likely to develop lung cancer than someone who does
not smoke and who has not been exposed to asbestos. If you work with asbestos
or have been exposed to it, the first thing you should do to reduce your chances of
developing cancer is to stop smoking.
Organizations that may offer programs, support, or information to help people
stop smoking are:
o OSU Wellness Center
o National Cancer Institute (1-800-4-CANCER)
o American Heart Association (1-800-242-8721)
o American Lung Association (in Oklahoma: 405-524-8471)
3. Age - cases of mesothelioma have occurred in the children of asbestos workers
whose only exposures were from the dust brought home on the clothing of family
members who worked with asbestos. The younger people are when they inhale
asbestos, the more likely they are to develop mesothelioma. This is why enormous
efforts are being made to prevent school children from being exposed.
Because each exposure to asbestos increases the body burden of asbestos fibers, it is very
important to reduce and minimize your exposure.
How to Avoid Asbestos Exposure
In order to avoid being exposed to asbestos, you must be aware of the locations it is likely
to be found. If you do not know whether something is asbestos or not, assume that it
is until it is verified otherwise. Remember that you cannot tell if floor or ceiling tiles
contain asbestos just by looking at them.
The OSU Environmental Health and Safety Department has a laboratory and a licensed
asbestos abatement crew that can take samples from materials in order to determine
whether or not they contain asbestos. If you need to have materials analyzed or tested for
asbestos, please contact EHS at X47241. Never try to take a sample yourself unless you
are licensed to do so.
If you have reason to suspect that something is asbestos, either because it is labeled as
such, or because it something that is likely to contain asbestos (9" floor tile, for example)
DO NOT DISTURB IT.
any asbestos-containing materials or suspected materials.
The EHS Asbestos Abatement Department has surveyed all campus buildings for the
presence of asbestos. If you need to do work that might involve asbestos (lifting ceiling
tiles, repairing insulated pipelines, etc.), check with EHS to find out what can be done
For example, before moving any ceiling tiles to perform maintenance work, it will be
necessary to ensure they do not contain asbestos. If they do contain asbestos, they will
need to be removed by licensed asbestos abatement workers before the work may be
Housekeepers and custodians should never sand or dry buff asbestos containing floor
tiles, and only wet stripping methods may be used during stripping operations. Low
abrasion pads should be used at speeds below 300 rpm.
Broken and fallen ceiling tiles should be left in place until identified. Only after they have
been identified as safe may they be removed. Asbestos tiles will be removed by asbestos
Broken and damaged asbestos floor tiles must also be removed by asbestos abatement
workers. Report any suspect broken tiles to EHS at X47241.
It is important to report any damaged asbestos-containing materials to OSU EHS at
X47241 immediately. If, for example, you discover some sprayed-on asbestos insulation
has been knocked off of a ceiling or wall, this would be considered a "spill." As such it
would need to be cleaned up immediately by asbestos abatement workers. Do not
attempt to clean up spills yourself! Disturb the material as little as possible. Also report
any damaged pipe insulation, ceiling tile, 9" floor tile, fallen clumps of sprayed-on
insulation, etc. Take measures to prevent others from disturbing the spill until the
Asbestos Abatement crew arrives.
By knowing where asbestos is likely to be located and then taking measures not to disturb
it, you will protect yourself and others from exposure to this hazardous substance.
What Is Asbestos?
Asbestos is a naturally occurring mineral. It differs from other minerals in its crystal
development. The crystal formation of asbestos is in the form of long thin fibers.
Asbestos is divided into two mineral groups --- Serpentine and Amphibole. Thedivision
between the two types of asbestos is based upon the crystalline structure. Serpentines
have a sheet or layered structure where amphiboles have a chain-like structure.
As the only member of the serpentine group, Chrysotile( A, B) is the most common type
of asbestos found in buildings. Also known as "white asbestos," Chrysotile makes up
approximately 90%-95% of all asbestos contained in buildings in the United States.
In the amphibole group, there are five types of asbestos. As an acronym for the Asbestos
Mines of South Africa, Amosite is the second most prevalent type of asbestos found in
building materials. Amosite is also known as "brown asbestos." Next, there is
Crocidolite or "blue asbestos," which is an asbestos found in specialized high
temperature applications. The other three types (Anthophyllite, Tremolite, and
Actinolite) are rare and found mainly as contaminants in other minerals.Asbestos
deposits can be found throughout the world and are still mined in Australia, Canada,
South Africa, and the former Soviet Union.
Over the years, asbestos has had many uses. Its primary use is as an insulator or fire
retardant, but can also be used as a binder. Due to this versatility, asbestos can be found
in many types of building materials. Even though the federal government placed a
moratorium on the production of mostasbestos products in the early 1970's, installation of
these products continuedthrough the late 1970's and even into the early 1980's.
Most health information on asbestos exposure has been derived from studies of workers
who have been exposed to asbestos in the course of their occupation. Asbestos fiber
concentrations for these workers were many times higher than those encountered by the
Because asbestos fibers are naturally occurring and extremely aerodynamic, virtually
everyone is exposed to asbestos. To be a significant health concern, asbestos fibers must
be inhaled at high concentrations over an extended period of time. Asbestos fibers then
accumulate in the lungs. As exposure increases, the risk of disease also increases.
Therefore, measures to minimize exposure and consequently minimize accumulation of
fibers will reduce the risk of adverse health effects.
Asbestos is only dangerous if it becomes airborne. As long as asbestos containing
materials are not damaged, the asbestos fibers do not become airborne and do not pose a
health threat to the building occupants. During an asbestos building survey, inspectors
assess the condition of asbestos containing materials. These conditions do deteriorate
over time. If you find that an asbestos containing item has been damaged, please contact
our office for a hazard assessment.
As asbestos fibers accumulate in the lungs, several types of diseases may occur.
Asbestosis is a scarring of the lung tissue. This scarring impairs the elasticity of the lung
and hampers its ability to exchange gases. This leads to inadequate oxygen intake to the
blood. Asbestosis restricts breathing leading to decreased lung volume and increased
resistance in the airways. It is a slowly progressive disease with a latency period of 15 to
The next type of disease attributed to asbestos exposure is Mesothelioma. It is a cancer
of the pleural lining. It is considered to be exclusively related to asbestos exposure. By
the time it is diagnosed, it is almost always fatal. Similar to other asbestos related
diseases, mesothelioma has a longer latency period of 30 to 40 years.
Lung Cancer is a malignant tumor of the bronchi covering. The tumor grows through
surrounding tissue, invading and often obstructing air passages. The time between
exposure to asbestos and the occurrence of lung cancer is 20 to 30 years. It should be
noted that there is a synergistic effect between smoking and asbestos exposure, which
creates an extreme susceptibility to lung cancer.
Airborne Fiber Concentrations
Asbestos is known to be hazardous based on studies of high levels of exposure to
asbestos workers and laboratory animals. However, the risks associated with lowlevel,
non-occupational exposure are not well established. Therefore, the Environmental
Protection Agency (EPA) concludes that there is no safe level of exposure to asbestos
fibers. On the other hand, the Occupational Safety and Health Administration (OSHA)
has set a Permissible Exposure Limit (PEL) at 0.1 fibers per cubic centimeter (f/cc) for an
8 hour time weighted average. Similarly, the Minnesota Department of Health (MDH)
has set the Clean Indoor Air Standard at 0.01 f/cc.
WHAT IS ASBESTOS?
Asbestos is a name given to a group of minerals which
occur naturally as masses of long silky fibers.
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 fibers are woven
together or incorporated within other materials to
create many products. There are three main types of
1- Chrysotile (White Asbestos): Fine, silky,
flexible white fibers (the most commonly used
asbestos in the United States and Canada).
Current evidence suggests that Chrysotile may be
less hazardous than Amosite or Crocidolite.
2- Amosite (Brown Asbestos): Straight, brittle
fibers that are light grey to pale brown (the
most commonly used in thermal system
3- Crocidolite (Blue Asbestos): Straight blue
There are three other types of asbestos fibers:
Anthopylite, Tremolite, and Actinolite, which are found
as contaminants in Asbestos Containing Materials (ACM).
WHAT IS THE PROBLEM WITH ASBESTOS?
People who work around or disturb asbestos are at risk
for developing asbestos associated diseases. The
occupational groups at the greatest risks for
developing asbestos associated diseases include:
janitors, maintenance personnel, construction workers,
insulators, plumbers, mechanics, telephone workers,
electrical workers, fire fighters, and asbestos
abatement workers. People who work, live, or attend
school in buildings containing asbestos products are
also considered at risk for developing asbestos
The U.S. Environmental Protection Agency (EPA)
considers there is no known safe level of asbestos
exposure. In the fall of 1990, the EPA developed a
policy, contained in the "Green Book" ("Managing
Asbestos in Place - A Building Owner's Guide to
Operations and Maintenance for Asbestos Containing
Materials"). This document summarized EPA's eleven
years of experience with asbestos. EPA recommends that
asbestos containing materials (ACM) in good condition,
can be maintained in place with very slight health risk
to the building occupants.
HOW IS ASBESTOS EXPOSURE CREATED?
ACM which can be crumbled, pulverized, or reduced to
powder by hand pressure is known as friable asbestos.
When friable ACM is damaged or disturbed it releases
fibers into the air. Airborne asbestos fibers are
small, odorless, and tasteless. They range in size
from .1 to 10 microns in length (a human hair is about
50 microns in diameter). Because asbestos fibers are
small and light, they can be suspended in the air for
long periods. People whose work brings them into
contact with asbestos may inhale fibers. A worker's
family may inhale asbestos fibers released by clothes
which have been in contact with ACM.
People who live or work near asbestos related
operations may inhale asbestos fibers that have been
released into the air by work activities.
The amount of asbestos a worker (anyone disturbing ACM)
is exposed to will vary according to several factors:
1- the fiber concentration in the air;
2- the duration of exposure;
3- the worker's breathing rate;
4- the weather conditions; and
5- whether or not protective equipment is worn.
Asbestos has been so widely used in the United States
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 fibers are released into the
environment from outcrops of bedrock in the earth. The
asbestos containing rocks release fibers as a result of
wind, water and chemical erosion.
WHAT ARE THE DISEASES CAUSED BY ASBESTOS
Once inhaled, the small, inert asbestos fibers can
easily penetrate the body's defenses. 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, each exposure
increases the likelihood of developing one or more of
the following diseases:
1- Asbestosis: 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
2- Mesothelioma: An asbestos caused cancer of the
chest cavity lining or abdominal cavity.
3- Other cancers: Cancer of the lung, esophagus,
stomach, colon, and pancreas.
Asbestos causes cancer. This is known from studies of
actual groups of asbestos workers, not inferred from
animal studies. The time it takes to develop lung
cancer is often fifteen years or longer. The time
frame for developing asbestosis and mesothelioma is
even longer. Many studies have shown the combination
of smoking and asbestos exposure to be particularly
hazardous. Cigarette smokers exposed to asbestos, on
the average are ten times more likely to develop lung
cancer than non-smokers.
HOW HAS ASBESTOS BEEN USED IN THE U.S.?
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. The
ship building industry used asbestos to insulate steam
pipes, boilers, hot water pipes, and nuclear reactors
in ships. Because of it's good friction and wear
characteristics, asbestos is often used in brake shoes
and clutch pads in cars, trucks, and airplanes.
In 1979, the United States' consumption of asbestos
amounted to 560,000 metric tons. By 1983, the annual
total consumption had dropped to 217,000 tons. This
reduction was due partially to regulatory actions,
which banned the use of asbestos in clothing, wallboard
patching compounds, some construction materials, and in
gas heaters. Asbestos was voluntarily withdrawn by
manufacturers of electric hair dryers in 1979.
WHERE CAN ASBESTOS BE FOUND?
Asbestos containing materials can be classified into
one of three types: sprayed or trowelled-on material,
Thermal System Insulation (TSI), or miscellaneous
1- Sprayed 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- TSI: 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, and
These suspect materials (materials which may contain
asbestos) are found in either a friable (can be crushed
or crumbled by hand pressure) or a non-friable state.
HOW MANY PUBLIC AND COMMERCIAL (P&C) BUILDINGS
ARE THOUGHT TO CONTAIN ASBESTOS?
Asbestos containing materials have been used
extensively in many public and commercial buildings in
the United States. In 1988 the EPA published a survey
of 3.6 million P&C buildings. The EPA survey gave the
following data showing the extent of asbestos use in
public and commercial buildings:
1- Friable asbestos was found in 733,000 buildings
2- Sprayed or trowelled on ACM was present in
192,000 buildings (5%).
3- Thermal System Insulation (TSI) was found in
563,000 buildings (16%).
4- 501,000 buildings (14%) contained damaged ACM.
5- 184,000 buildings (5%) contained moderately
6- 317,000 buildings (9%) contained severely
Of the 733,000 public and commercial buildings
containing friable asbestos, the following was found:
1- 511,000 buildings (70%) were private, non-residential
2- 208,000 buildings (28%) were apartments with ten
or more units.
3- 14,000 buildings (2%) were Federal Buildings.