Asbestos is a natural mineral that soft, flexible, long-lasting,
resistant to heat, fire, electricity and chemical corrosion. The pure asbestos
is an effective insulator and it can become stronger after mixed into cement, cloth,
paper, plastic and other materials. However, these materials can bring many
consequences to a human body after human inhale it unconsciously or ingested
accidentally. The asbestos may lodge in
the soft tissues of the abdomen or lungs after entering the human body. Then, the
body will face difficulty in expelling the fibres and eventually lead to many health
complications such as lung cancer, asbestosis and pleural mesothelioma.
There are six types of
asbestos fibres which fall into two categories of silicate fibres which are serpentine
and amphibole asbestos. The serpentine asbestos composed of long and curly fibres.
It only has one example which is chrysotile that appears in white in colour but
it may also in grey, green, or yellow. This is the most commercially used form
of asbestos. Besides that, the examples of amphibole asbestos is amosite,
crocidolite, tremolite, actinolite and anthophyllite. These minerals are more
hazardous than chrysotile when inhaled or ingested because it composed of
brittle, rod- or needle-shaped fibres.
amosite asbestos that acid-resistant
are available in brown, ash grey, or green in colour. Crocidolite asbestos that also acid resistant but less heat
resistant are appear in bluish colour while anthophyllite asbestos that extremely resistant to acid are available
in green, greyish white, and brownish grey. Tremolite asbestos that can be found in white or grey colour
can be in non-asbestos form and it is resistant to acids too. Actinolite asbestos is a derivative of
tremolite and it also can occur in non-asbestos form. However, it does not
resistant to acids and appears as pale to dark green.
Figure 1 above shows type of asbestos, from the
left to right (chrysotile, amosite, crocidolite, anthophyllite, tremolite, and
measures refer to any action that can be carried out to reduce the exposure potential
to the hazard or to remove the hazard.
The table 1 below shows the control measures for
asbestos according to the hierarchy of control measures.
1. Eliminate the hazard
Elimination is the best way to prevent the hazard (asbestos) from
harming a human. Elimination can be carried out by only use non-asbestos
containing product but it is not always achievable because there are still the
risk of exposure to asbestos from the environment such as mines.
2. Substitute the hazard with a lesser risk
Substitute the hazard (asbestos) with materials that is
less hazardous than asbestos may not totally remove the hazards but still
able to reduce the health effects overall. However, if able to substitute the
asbestos with the non-hazardous material then may totally eliminate hazard
from the human.
3. Engineering controls (Isolate the
Isolating the hazard (asbestos) can be achieved by limiting access to
the hazard by securing them away from human under strict controls or changing
the work process by creating a barrier between a person and the hazard in
order to reduce the health risk or remove the hazard from the person.
4. Administrative controls
Administrative controls include providing training to the people who will
expose to the hazard (asbestos). This enables them to know the standard and
safe operating procedures, accurate instruction or information in order to
reduce the potential for hazard.
Personal protective equipment (PPE) usually seen as the last line of
defence and the least effective method because it does not eliminate the
hazard and the involved person will not be protected if the equipment is
inadequate or fails. PPE may cause uncomfortable and exert additional
physical burden or even create more consequences onto the worker too. For
example, the long-term use of respirators can put a pressure on the lungs and
heart especially to the workers who in contact with asbestos, they have to
wear sufficient personal protective equipment all the time during work.
As mentioned above, there are few options for
control measures against the asbestos. When planning or choosing the suitable
hazard controls, people are recommended to choose the first line defence
(elimination) if available and do not choose the control measure that can create
another hazard or problem after eliminating one hazard (asbestos).