Asbestos is a natural mineral that soft, flexible, long-lasting,resistant to heat, fire, electricity and chemical corrosion. The pure asbestosis an effective insulator and it can become stronger after mixed into cement, cloth,paper, plastic and other materials. However, these materials can bring manyconsequences to a human body after human inhale it unconsciously or ingestedaccidentally. The asbestos may lodge inthe soft tissues of the abdomen or lungs after entering the human body. Then, thebody will face difficulty in expelling the fibres and eventually lead to many healthcomplications such as lung cancer, asbestosis and pleural mesothelioma. There are six types ofasbestos fibres which fall into two categories of silicate fibres which are serpentineand 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 butit may also in grey, green, or yellow. This is the most commercially used formof asbestos. Besides that, the examples of amphibole asbestos is amosite,crocidolite, tremolite, actinolite and anthophyllite. These minerals are morehazardous than chrysotile when inhaled or ingested because it composed ofbrittle, rod- or needle-shaped fibres. Moreover,amosite asbestos that acid-resistantare available in brown, ash grey, or green in colour. Crocidolite asbestos that also acid resistant but less heatresistant are appear in bluish colour while anthophyllite asbestos that extremely resistant to acid are availablein green, greyish white, and brownish grey.
Tremolite asbestos that can be found in white or grey colourcan be in non-asbestos form and it is resistant to acids too. Actinolite asbestos is a derivative oftremolite and it also can occur in non-asbestos form. However, it does notresistant to acids and appears as pale to dark green. Figure 1 above shows type of asbestos, from theleft to right (chrysotile, amosite, crocidolite, anthophyllite, tremolite, andactinolite asbestos).
Controlmeasures refer to any action that can be carried out to reduce the exposure potentialto the hazard or to remove the hazard. The table 1 below shows the control measures forasbestos 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 hazard) 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. 5.
Personal protective equipment 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 forcontrol measures against the asbestos. When planning or choosing the suitablehazard controls, people are recommended to choose the first line defence(elimination) if available and do not choose the control measure that can createanother hazard or problem after eliminating one hazard (asbestos).