As long ago as 100 AD, the Roman naturalist Pliny the Elder remarked that workers in asbestos mines developed a sickness of the lungs. But the use of asbestos stretches back into pre-history, with asbestos mines discovered that date back to 5,000 BC. The fibres were apparently used as lamp wicks, while the Egyptians and subsequent civilisations recognised the fire retardant and preservative nature of asbestos, which was woven into shrouds and household textiles.
In Australia, asbestos was used in a variety of building materials for fireproofing up until the 1980s, when the medical evidence became too overwhelming to ignore – asbestos was a silent killer. Today, asbestos still lurks among us in the form of old roofs, ancient insulation and crumbling backyard sheds, and asbestos detection is a major industry. You should never try to remove any material you suspect of being asbestos, as to do so could generate particles that you may inhale.
Monitoring asbestos levels and enclosures
After asbestos inspection has been conducted and its presence confirmed, the removal procedure begins. To stop any airborne particulate escaping the immediate area, the space containing the asbestos is enclosed and negative air pressure applied to it, which draws escaping particles back inside. Safety guidelines for asbestos removal call for constant air monitoring, and if a presence of 0.02 asbestos fibres per millilitre of air is detected, the removal process must be halted and reviewed – an indication of how serious the threat is.
Wet method of asbestos removal
Like any dust or fibre, asbestos responds to dampening down, and the wet method of removal is preferred, although there are cases where this is impossible. A fine, low pressure spray of water is applied to surfaces before removal and a wetting agent such as detergent is added to help bind the water to the fibres. This spray is applied to the material at the point where it is being cut. In cases where the asbestos is so thick that the spray cannot reach far enough into the material, a method of saturation is used where water is injected into the material through a series of holes.
Asbestos vacuum cleaners
You cannot use your household vacuum cleaner on asbestos, even if it is a Dyson! The filters are simply not safe enough to contain all the particles. Specialist companies hire out asbestos vacuum cleaners, since getting rid of the contents of the vacuum cleaner is also a hazardous task. During the use of the vacuum cleaners, and during the entire extraction process, asbestos removalists must wear protective clothing that is made from a dust repellent fibre. Wool is not a suitable fibre, for example, because it traps dust. Coveralls used during removal are disposable, but if they need to be reused, they must be sent to a commercial laundry for specific type of treatment. Respirators must be used during asbestos removal.
Facilities for asbestos removalists
There are three contamination areas that need to be set up at the removal site: one ‘dirty’ and two ‘clean’. The dirty area, where workers first go when they emerge from an enclosure, consists of racks for shoes and clothing, waste bags for removal of contaminated attire, and a shower. The first clean area is where respirators are stored, and contains another showering facility, with negative airflow back to the dirty area. Finally, there’s a second clean area where workers’ clothes and personal items are kept. Entering or leaving the site, removalists pass through these three phases.
The removal of asbestos is a complex task requiring specific equipment and adherence to safety standards set down by the Australian Government. While asbestos remains with us for the time being, its removal should pose no harm to us if done according to industry standards. Contact us to find out more about asbestos identification and removal.