Asbestos
Asbestos is a silicate mineral mined from the earth
in much the same way as any other mineral. The wide use of asbestos over thousands of years is due to its resistance to heat and chemicals. Most asbestos went into buildings or ships as pipe and boiler lagging, fire insulations panels and asbestos cement sheets. There are hundreds of other asbestos products and processes.
The health effects of exposure to asbestos fibres are well known today. It is deadly to breathe in asbestos fibre; inhalation of even a small amount can lead to deadly illnesses like cancer and mesothelioma. It is essential that you follow the strict safe working methods and procedures that are legal requirements for any person working with any products containing asbestos in NSW.
What Has Asbestos
Been Used For?
Asbestos has been sprayed in buildings for acoustic
(noise-proofing) and decorative purposes since the 1940's. By the late 1950's,
it became virtually standard practice for all large multi-storey buildings, and
many hospitals and schools, to have asbestos sprayed on their steel girders for
fireproofing. As a result many workers and even children in schools can be at
risk from exposure to asbestos insulation in
buildings.
The main
uses for asbestos were as:
− Insulation material such as pipe lagging
− Asbestos-cement fibro products
− Building insulation materials
− Sprayed on fire-proofing and decorative material
As the serious health effects of asbestos
became apparent its widespread use in buildings has become an enormous problem.
For example, sprayed asbestos will deteriorate
over time, and if uncontrolled will crumble and send fibres into the air where
they could be breathed in by people in the surrounding area and even circulated
around a building by air conditioning systems.
The demolition of buildings with asbestos
insulation or lagging has the potential for the release of massive amounts of
asbestos fibre unless stringent precautions are taken.
Where Is Asbestos
Found?
Most asbestos went into buildings or ships as pipe
and boiler lagging, fire insulations panels and asbestos cement sheets.
There are hundreds of other asbestos products
and processes, including:
− Insulation – sprayed onto structures; fire
blankets, gloves, pads; string, tape, paper; insulation board;
− Friction Materials – clutches; disc brake
pads; brake linings;
− Reinforced Products – asbestos cement
slabs, sheeting, pipes; floor tiles; composite board; roofing felt; underseals,
paints; gaskets, washers,
valve-packing.
Asbestos is likely to be in a
building if:
− It was built or refurbished between 1950 and
1980 in particular;
− It also has a steel frame; and/or
− It has boilers with thermal
insulation.
Types Of
Asbestos
WHITE ASBESTOS (Chrysotile) - Fibres are curly and
difficult to separate. They are white to grey in
colour.
BROWN ASBESTOS (Amosite) The type of
asbestos found most often in sprayed insulation
materials.
BLUE ASBESTOS (Crocidolite) -
Encountered in maintenance and removal work. Its fibres are straight and
coloured dark blue.
In Australia, asbestos has
been in commercial use since 1920. State and Federal Governments have banned the
importation and use of asbestos from January 1 2004.
However, significant quantities of both
CHRYSOTILE and CROCIDOLITE (blue asbestos) remain in installations and exposure
can still occur.
Health
Effects
There is no "safe" level of exposure to
asbestos.
The more asbestos fibres you are
exposed to, the greater the risk of getting asbestos related disease. This is
why it is so important to prevent exposure in the first place.
Asbestos is known to be very toxic, especially
following prolonged exposure. Breathing in very small fibres of asbestos causes
the ill health effects of exposure to asbestos.
Diseases caused by asbestos are asbestosis,
lung cancer, mesothelioma and other cancers. Large numbers of Australian workers
are still being diagnosed with asbestos related illnesses, many years after they
were exposed. Many of these workers will die.
ASBESTOSIS - Progressive scarring
(fibrosis) of the lung, leading to pain, breathlessness, and, eventually death.
The first symptoms can appear 15 to 20 years after exposure. There is no known
cure.
LUNG CANCER - Tumours of the
bronchial tubes and lungs, occurring up to 25 to 30 years after first exposure,
and normally fatal. The risk increases greatly in workers who smoke. The
International Confederation of Free Trade Unions estimate that at least one in
ten cases of lung cancer are caused by exposure to asbestos.
MESOTHELIOMA - Is a cancer of the
lining of the chest (pleura) or of the abdomen (peritoneum). This tumour
thickens the lining and may eventually totally enclose the lung. It is painful
and invariably fatal.
OTHER CANCERS -
Cancers of the larynx, stomach, large intestine and possibly of the ovary,
breast, kidney and bone marrow.
Other
indications of asbestos exposure are:
− Pleural plaques - patches of thickening of the
lining of the chest wall and over the diaphragm;
− Pleural effusion – a collection of fluid
within the chest but outside the lung.
Who Is Most At
Risk?
The most serious risk is for workers involved in the
removal of the asbestos itself, the demolition of buildings with asbestos in
them, and maintenance or renovation work on the areas of a building containing
asbestos. By knowing what precautions are
necessary when asbestos work is being done, workers can make sure that their
health is not being threatened by exposure to deadly asbestos
fibres.For more
specific information on legislative requirements and guidelines on safe asbestos
removal see the publications listed under Useful
References at the end of this Fact Sheet.
Smoking And
Asbestos
The health effects of asbestos strike at smokers and
non-smokers alike, but cigarette smoking greatly increases the risk of death
from lung cancer in people who are exposed to asbestos.
Workers exposed to asbestos are 10 times more
likely to develop lung cancer than unexposed general population. In workers who
smoke and have a high exposure to asbestos this risk of lung cancer can be up to
100 times.
What Does The Law Say
About Asbestos?
In NSW the most important laws covering asbestos
come under the NSW Occupational Health and Safety Act 2000 and the NSW
Occupational Health and Safety Regulation 2001
Controllers of Premises
Responsibilities
Under the Occupational Health and Safety Regulation 2001 there are responsibilities for controllers of premises. A
controller of premises that contain asbestos or asbestos containing material
must ensure that Risk Assessment and Control Measures are carried out.
The controller of premises is defined under Clause 33 of the Occupational Health and Safety Regulation
2001 as a person who has control of premises used by people as a
place of work. This includes a person who only has limited control of the
premises and a person who has, under any contract or lease, an obligation to
repair or maintain the premises.
Keeping Register of
Asbestos
A controller of premises must ensure
that:A register, in which the type, condition
and location of all asbestos and asbestos containing material in any workplace
is prepared, recorded and maintained. For example, if it is contaminated roof
tiles or in the walls of a building a register must be kept of these
details.Any action taken to control asbestos
and asbestos containing material in the workplace or in plant at the workplace
is recorded in the asbestos register. The register must be easily accessible to
everyone in the workplace, including contractors and visitors (e.g.
electricians, plumbers and others who may perform work in asbestos contaminated
areas).They must also include details of
assessment concerning the asbestos that took place before any work was carried
out. If a contractor carried out the work
rather than by an employee of the controller of premises then the name of the
person who carried out the work and date on which the work was carried out must
also be registered. For example, was the asbestos disturbed in any way and if so
what measures were put in place to seal any potential
exposure.Employers’
Legal RequirementsEmployers are required
to identify, assess and control both stable asbestos and asbestos in processes.
This involves requirements in the design of workplaces and plant, labelling,
notifying WorkCover in certain circumstances, controlling the exposure,
providing training and consulting with employees and health and safety
reps.An employer must ensure that asbestos
work is carried out within the legal requirements of the NSW OHS
Legislation.The National Code of Practice
for the Safe Removal of Asbestos (National Occupational Health & Safety
Council Australia, 1988) sets out the minimum industrial hygiene
procedures to be used for the removal of asbestos insulation material such as
lagging and sprayed asbestos. Guide to the
Control of Asbestos Hazards in Buildings and Structures [NOHSC: 3002
(1988)], and; Code of Practice for the Safe Removal of Asbestos [NOHSC:
2002 (1988).(If a requirement of clause 51
(Atmospheric contaminants—particular risk control measures) is
inconsistent with a requirement of this subclause, the clause 51 requirement
prevails).There is another requirement under
the clause 51 of the OHS Regulations 2001 that refers to atmospheric
contaminants. This is the clause that has precedence (is more important than)
the NOHSC guidelines.Employers must ensure
that:- Employees and other persons
contracted to carry out asbestos work are informed of the dangers involved and
of any precautions that should be taken.
- Employees must be provided with:
- Training
- Safe Work Method Statements
- Personal Protective Equipment (PPE)
- Facilities to safely wash and remove PPE and clothing
before they leave the workplace.
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- Employees are
notified in writing if asbestos work is being carried
out.
All persons must be warned, by the use of
signs, labels or other similar measures, of the presence of asbestos or
asbestos-containing material in a place at which work is being carried out
around asbestos.
- Employers must identify,
and implement measures to prevent any disturbance of asbestos-containing
material while work is being carried out.
For
example, if asbestos is encapsulated, or sealed, the employer cannot allow any
asbestos fibres to be released into the air – they must seal off the
asbestos and areas where it exists.
An employer
must ensure that procedures are in place for:
-
The cleaning of premises at which asbestos work is carried out,
and
- The laundering and cleaning of personal
protective equipment used for asbestos work,
and
- The containment of asbestos waste,
and
- The disposal of asbestos and
asbestos-containing material safely according to Environmental Protection
Authority standards and guidelines (e.g. disposed of to a legitimate hazardous
waste facility).
An employer must ensure that
no asbestos-containing material, including asbestos cement, is reused in
connection with the carrying out of construction
work.
An employer must not use high-pressure
hoses to clean the surface of asbestos-containing material, including asbestos
cement or any structures that consist of or contain asbestos, during the
carrying out of construction work.
Occupiers’ Legal
Responsibilities
Occupiers also have requirements to identify, assess
and control asbestos, in workplace design and to notify
WorkCover.
Designers,
Manufacturers, Importers And Suppliers Legal Responsibilities
Designers, manufacturers, importers and suppliers
have design and labelling requirements.
Workers Exposed To
Asbestos
If you or other workers are exposed to asbestos the
employer must ensure that:
- Records are kept of exposure
- Provide ongoing medical examinations, and
- Provide ongoing health surveillance
Medical
ExaminationsUnder the NSW Occupational
Health and Safety Regulation 2001, the constructor (or removal contractor)
must arrange for medical examinations for workers exposed to asbestos in removal
or other construction work.
The Exposure
Standard
Legally an employer must ensure that no person at a
place of work is exposed to an airborne concentration of an atmospheric
contaminant that exceeds or breaches a standard referred to in or determined
under clause 51, subclause (2) of the OHS regulation
2001.
The Exposure Standard sets out the
time weighted average fibre concentration in the air breathed by a worker. This
is on the basis of the amount of exposure that an employee may be exposed to
during an eight-hour working day, five-day working week. For example, the
experts place a monitor on a worker to measure the average time that a worker is
exposed to a substance.
The exposure standards
are as follows:
White Asbestos (chrysotile) 0.1
fibre per millilitre of air
Blue Asbestos
(crocidolite) 0.1 fibres per millilitre of air
Brown Asbestos (armosite) 0.1 fibres per
millilitre of air
Monitoring Asbestos
Levels And Health
Your union or the NSW Workers Health Centre (Phone
(02) 9749 7666) can help conduct tests for asbestos exposure
levels.
Health Surveillance
(Monitoring)
Employers must provide health surveillance for each
employee who is exposed to a hazardous substance, including asbestos, if there
is a risk to the health of the employee as a result of
exposure.
An employer must provide biological
monitoring for an employee if there is a reasonable likelihood that the employee
could be exposed to levels of asbestos that could be a risk to
health.
The employer must ensure
that:
- The health surveillance is performed under the
supervision of an authorised medical practitioner, and
- The selection of the authorised medical practitioner
to supervise the health surveillance must be undertaken by the employer after
consultation with relevant employees.
This
health surveillance must be undertaken at the expense of the
employer.
Dust Diseases
Board
The Dust Diseases Board also conducts health
monitoring in the area of asbestos.
The Dust Diseases Board is a NSW statutory authority
established under the Workers' Compensation (Dust Diseases) Act 1942.
Under the Act, the Dust Diseases Board is required to:
• Determine eligibility and award compensation to
workers who are suffering from dust diseases such as mesothelioma, and
dependants of deceased workers.
• Determine the classes of employment in any
industry or process that expose workers to the risk of contracting a specified
dust disease.
• Administer the Workers' Compensation (Dust
Diseases) Fund, the Dust Diseases Reserve Fund and pay all compensation, awards,
research grants, fees, salaries and all other costs of administration of the Act
including the operating expenses of the Dust Diseases Tribunal.
• Make an estimate each year of the amount of
compensation to be paid to workers and dependants of deceased workers.
• Administer the trust funds held on behalf of the
dependants of deceased workers.
The NSW Workers' Compensation Dust Diseases Board can be
contacted on (02) 8223 6600 or Toll Free on 1800 550 027
The Dust Diseases Board also operates the Occupational
Respiratory Screening Service and the Mobile Respiratory Screening Service (Lung
Bus) Tel: 1800 727 333
What To Do About
Asbestos
In Australia and overseas,
there has been much discussion over what should be done about asbestos in
buildings. There are basically four options:
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Label it
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Leave the asbestos intact (but labelled) if it is in
good condition, unlikely to be disturbed and unable to feed fibres into workers'
breathing zones.
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Enclose it
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Enclose the asbestos so that disturbance of the asbestos
material and entry into the enclosure is not possible.
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Seal it
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Encapsulate (or deep seal) the asbestos, if it is in
good condition and unlikely to be disturbed.
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Remove it
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Remove the asbestos if its surface is damaged or
crumbling, or it is likely to be disturbed, for example, by maintenance
work.
Removal of asbestos obviously eliminates
the hazard forever - provided it is done with the best control procedures, with
competent removal experts, good supervision and a well informed workforce. But
often this is not the case in practice.
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The National Code of
Practice for the Safe Removal of Asbestos introduced strict licensing
requirements and regulations for asbestos removal contractors.
There was an argument in favour of temporary
sealing in the past, but now only electrical equipment can be temporarily
sealed.
Easy Guide To Handling
Asbestos
Removal, Treatment or Sealing
Of Asbestos
Where significant amounts of asbestos dust may be
present because asbestos has been broken to remove it from a confined area (e.g.
ceiling of a room) the wearing of disposable overalls and gloves should occur.
Removed asbestos sheets should be disposed in
polyethylene sheeting, wrapped and sealed into appropriate bundles for disposal.
Broken asbestos sheeting and associated wastes
should be placed directly into disposal bins (skips) that have been lined with
polyethylene sheeting or placed in heavy duty, 0.2 mm thick polyethylene plastic
bags.
The bags should be no larger than 1200
mm by 900 mm. Bins and bags should be sealed for removal. To make handling and
sealing easier, bags should only be partially
filled.
Some simple procedures to ensure safety
to all workers when removing asbestos products:
− When asbestos products are being removed, signs
and barriers must be erected to warn of the danger and to prevent unauthorised
people entering.
− All people in the asbestos removal area must
wear disposable coveralls and a suitable half face respirator.
− Asbestos must be sprayed with a poly vinyl
acetate (PVA) solution or kept wet with water during removal. Care must be taken
on roofs because Asbestos Cement sheets are brittle and slippery when wet.
− Non-powered hand tools or portable power tools
incorporating dust suppression or dust extraction attachments designed to
collect asbestos fibres must be used.
− Asbestos products must be removed with minimal
breakage, and lowered to the ground, not dropped.
− Removed sheets are to be stacked on polythene
sheeting, then wrapped and sealed into bundles for disposal, or placed directly
into disposable bins that have been lined with polythene sheeting, and sealed
for disposal.
− Asbestos sheets must not be left lying about the
site where they may be further broken or crushed by machinery or site traffic.
− When removed asbestos sheets are being stacked,
care must be taken not to skid one sheet over another, as this will result in
the release of fibres.
− Roof gutters must be cleaned or sealed prior to
their removal.
− Any asbestos visible residue remaining in the
roof space or within the removal area is to be cleaned up, using an approved
vacuum cleaner if necessary.
− All waste containing asbestos is to be kept wet,
wrapped in polythene or otherwise sealed, and removed from the site as soon as
practicable.
− Used disposable coveralls and masks are to be
placed in bags for removal with other asbestos waste.
Safe Work Method
Statements
If there is any potential exposure of employers,
self-employed, workers or members of the public to asbestos fibres, employers
should ensure appropriate respiratory protection is available.
Airborne asbestos fibre contamination should
be minimised by observing correct work practices.
The employer should ensure that people
involved in the removal or treatment of asbestos-cement sheeting undertake
safety training and familiarisation with the proposed work before
commencing.
All employees involved in the
removal of asbestos cement sheeting must follow the recommended safe work method
procedures, which must be developed by the employer including contractors and
any other personnel involved.
Disposal Of Asbestos
Material
Transport and final disposal of asbestos material
should be carried out in a way that prevents the release of asbestos fibres.
Because there is a risk of the asbestos-cement
waste breaking down resulting in airborne asbestos fibre contamination, all
asbestos materials are to be disposed of at an approved site, which is under the
control of the local authority and, in accordance with the environmental
legislative requirements.
Asbestos- waste
should not be used as fill in the construction or repair of roads and vehicle
parking areas.
Personal Protective
Equipment
In undertaking the removal or treatment of
asbestos-cement sheeting the appropriate personal protective equipment should be
worn.
Personal Protective Equipment Should
Never Be Removed From A Site Where Asbestos
Exists
All personal protective respiratory
equipment (RPE) should be of an approved type.
For example, respiratory protective devices
manufactured to the standard AS/NZS 1716.
Check that all respiratory protective devices
meet this standard.
Respiratory
Protection
There is a wide range of respiratory protection
available for airborne asbestos dust.
In
general, the nature of the asbestos work and the probable maximum concentrations
of asbestos dust that would be encountered in this work determine the selection
of a particular respirator.
The proper fitting
of respiratory protective equipment requires the use of some type of
“fit” test to determine an adequate match between the face piece of
the respirator and face of the wearer.
The
personal characteristics of the wearer will affect the facial fit of the
respirator especially the amount of facial hair, or whether glasses are worn.
The supplier of the respiratory protective equipment should be consulted for
further advice.
Types Of
Respirator
The following list provides, in approximate order of
increasing efficiency, an indication of some respirators, which may be used for
protection against asbestos dust.
− Disposable, half-face particulate
respirators
− Half-face, particulate filter (cartridge)
respirator
− Powered, air-purifying, ventilated helmet or
hood respirator
− Full-face, particulate filter (cartridge)
respirator
− Full-face powered air-purifying particulate
respirator
− Full-face, positive pressure demand airline
respirator
− Full suit or hood, continuous flow, airline
respirator.
Protective
Coveralls
Disposable fibre proof coveralls should be used over
other clothing. If coveralls are not disposable, then the employer is
responsible for laundering contaminated clothing. Coveralls with Velcro type
seals are not suitable for asbestos work
Wear
old clothes beneath your coveralls. When you have finished work put disposable
coveralls into a rubbish bag and seal it. Do this before you remove your mask.
Don't allow anyone else to touch the coveralls. If not using disposable
coveralls ensure that any laundry container for non-disposable coveralls is
firmly sealed. Use of non-disposable coveralls is not
recommended.
Never sweep up. Always use a
vacuum cleaner that has an internal sealed and removable bag. Put the vacuum bag
carefully into a rubbish bag and seal it. Keep your mask on while you do
this.
Put any discarded material in a strong
rubbish bag and seal it. Only Then remove your mask and disposable
coveralls and seal them in the rubbish bag.
Shower thoroughly immediately after finishing
work, on site so as not to carry fibres home to your friends and
family.
Action Plan For Health
And Safety Representatives
Keep the workforce informed at all times.
− Conduct an asbestos risk assessment
− A register of asbestos should be kept by the
controller of premises
− Make sure management identify asbestos, develop
an action plan to deal with it and stick to that plan.
− Assume that walls, ceilings and lagging contain
asbestos unless certain they don’t.
− Insist that all work with asbestos complies with
the Occupational Health And Safety Regulations 2001
− Make sure that any OHS Committee meeting minutes
record all matters relating to asbestos issues, and that these records are kept
in a safe area for future reference.
Other
Useful References
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ASBESTOS REMOVAL CHECKLIST
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YES
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NO
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Before Asbestos work commences is there adequate warning
signage of the dangers and appropriate equipment to be used if entering the work
site.
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Is all equipment used for the removal of asbestos
material inspected before commencement?
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Is personal protective equipment including coveralls and
a suitable respirator used? (Coveralls with Velcro type seals are not suitable
for asbestos work)
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Are there any tools being used on Asbestos i.e., abrasive
cutters and sanders, as these generate dust?
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If the answer to the above question is YES, are hand
tools rather than power tools being used?
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Is there wet methods used to dampen down
material?
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Are suitable vacuum attachments fitted
with
High Efficiency Particulate Air (HEPA) filters
to reduce the release of dust?
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Are all work procedures devised to minimise the release
of dust and fibres?
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Is waste disposed of and dust collected in plastic bags,
which are clearly labelled asbestos waste?
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Are drop sheets used to collect debris, with precautions
taken to prevent slip and trip hazards?
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Is asbestos waste transported in a covered leak-proof
vehicle and/ in a manner approved by the EPA?
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Is asbestos waste disposed of in a manner and at a site
that is approved by the EPA or an appropriate disposal authority?
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Are licensed professionals conducting the asbestos
removal work?
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Are masks used during asbestos removal approved to
Australian Standard AS1715 to protect against asbestos?
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When you have finished work have you showered thoroughly
immediately after finishing work and ensured that any Protective masks and
coveralls have been disposed of securely in plastic PVC bags?
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See Also Fact Sheet
On:
Air
Quality
Material Safety Data
Sheets
Personal Protective
Equipment
Risk Assessment
Frequently
Asked Questions regarding Asbestos
What should you do if you have
already worked with or been exposed to asbestos?
Make sure your employer, your doctor and your union
have a record of your asbestos exposure, and if you get any of the asbestos
diseases, contact your union for assistance in seeking compensation.
Asbestos diseases usually take many years to
appear, so medical checks straight after exposure may detect nothing. Such
checks will not cure asbestos diseases – they just help to identify some
of them earlier. However, some workers may benefit from stopping further work
with asbestos if disease is detected, and some ill-health can be helped by early
detection. Regular medical check-ups must be according to the National
Occupational Health and Safety Commission’s “Guidelines for Health
Surveillance”. You must tell your doctor how you have been exposed to
asbestos dust, where and for how long.
If you
smoke, try to stop or cut down. Your risk of lung cancer begins to drop the day
you stop smoking.
What Is Asbestos?
Asbestos is a mineral which has been mined extensively
and processed for many commercial applications throughout the world. It is
commonly known in its various forms as blue asbestos (crocidolite), brown
asbestos (amosite), or white asbestos (chrysotile).
The resistance of asbestos to fire and chemical
breakdown and its fibrous structure are properties which have made it so useful
in many products. We are familiar with its use in building material as asbestos
cement sheeting, insulation and various fireproof fabrics. It has also gained
entry into homes in other forms such as ironing blankets, simmering pads for the
top of stoves and the contamination of talcum powder.
How Does Asbestos Get Into The
Body?
Asbestos fibres can become airborne because they are
very fine. Some of them are small enough to get through the smallest airways of
the lung (diag. 1a and 1b) to end up in the air sacs where the oxygen gets into
the blood.
Asbestos can also be swallowed.
Inhaled fibres are the cause of asbestos lung diseases.
Also it is possible that swallowed fibres cause peritoneal (abdominal)
mesothelioma.
Is All Asbestos
Harmful?
All types of asbestos are unsafe for
humans.
The three forms of commercial asbestos which have been
used in Australia are all harmful. There is no amount of asbestos exposure low
enough to be guaranteed 100 per cent free of health risk.
As well as causing several diseases affecting health,
asbestos can also cause pleural plaques. These plaques usually are not
associated with any ill effects but occasional individuals may have
pain.
What diseases does asbestos
cause?
It is known that asbestos causes the following
diseases
• Benign related pleural disease
• Lung cancer
• Mesothelioma
• Asbestosis
None of these diseases can be spread to other people
because they are not infectious.
What is benign asbestos related
pleural disease (ARPD)?
ARPD usually begins with an inflammation of the pleura
leading to fluid collecting in the space between the lung and the chest wall.
This may be associated with some discomfort, but most usually it causes
shortness of breath that may come on over days or weeks.
What treatment is available for
benign asbestos related pleural disease (ARPD)?
Removal of the fluid is usually indicated and is
followed by immediate relief of breathlessness. This is a small procedure done
with local anaesthetic and it may need to be repeated if the fluid gathers
again.
The fluid eventually stops coming back if nothing is
done and the lung pleura may begin to thicken. This pleural thickening can be
seen on x-ray of CT scan. Because the thickening of the pleura tends to squeeze
the lung it may cause shortness of breath.
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