The National Occupational Health and Safety Commission (NOHSC) has produced the "Code of Practice for the Safe Removal Of Asbestos 2nd Edition" [NOHSC: 2002(2005)].
The following is an extract from this document which outlines the potential health hazards from asbestos.
PART 6: HEALTH ASPECTS OF EXPOSURE TO AIRBORNE ASBESTOS FIBRES
Asbestos is a known carcinogen. The inhalation of asbestos fibres is known to cause mesothelioma, lung cancer and asbestosis.
Malignant mesothelioma is a cancer of the outer covering of the lung (the pleura) or the abdominal cavity (the peritoneum). It is usually fatal.
Mesothelioma is caused by the inhalation of needle-like asbestos fibres deep into the lungs where they can damage mesothelial cells, potentially resulting in cancer
The latency period is generally between 35 and 40 years, but it may be longer, and the disease is very difficult to detect prior to the onset of illness.
Mesothelioma was once rare, but its incidence is increasing throughout the industrial world as a result of past exposures to asbestos. Australia has the highest incidence rate in the world.
Lung cancer has been shown to be caused by all types of asbestos. The average latency period of the disease, from the first exposure to asbestos, ranges from 20 to 30 years. Lung cancer symptoms are rarely felt until the disease has developed to an advanced stage.
Asbestosis is a form of lung disease (pneumoconiosis) directly caused by inhaling asbestos fibres, causing a scarring (fibrosis) of the lung tissue which decreases the ability of the lungs to transfer oxygen to the blood. The latency period of asbestosis is generally between 15 and 25 years.
Asbestos poses a risk to health whenever asbestos fibres become airborne and people are exposed to these fibres.
Accordingly, exposure should be prevented. The national exposure standard (NES) of 0.1 fibres/mL should never be exceeded, and control measures should be reassessed whenever air monitoring indicates the 'control level' of. 0.01 fibres/mL has been reached (see section 9.8.1 of this code, and also see the Code of Practice for the Management and Control of Asbestos in Workplaces [NOHSC: 2018 (2005)].
Asbestos-Containing Materials (ACM) can release asbestos fibres into the air whenever they are disturbed, and especially during the following activities:
any direct action on ACM, such as drilling, boring, cutting, filing, brushing, grinding, sanding, breaking, smashing or blowing with compressed air (State and Territory legislation prohibits most of these actions, and the relevant laws should be checked before performing any activity on ACM):
- the inspection or removal of ACM from workplaces (including vehicles, plant and equipment);
- the removal of materials from vehicles, plant, equipment or workplaces; and
- the renovation or demolition of buildings containing ACM.
Non-friable ACM that has been subjected to extensive weathering or deterioration also has a higher potential to release asbestos fibres into the air.
Health surveillance is an important part of the monitoring of exposure to hazardous substances, including asbestos, to ensure the health and safety of people in workplaces.
Information on health surveillance requirements for asbestos removalists is provided in section 7.3.6 of this code of practice.