The first indication of asbestos is the age of the material/building. If the building was constructed before 1987 there is a very good chance that it contains asbestos. It should be noted that any building constructed before 31 December 2003 may contain asbestos.
Asbestos is a fibre material. If looking at it with a close eye you can determine what asbestos type it is. It will either be white and straight with splayed ends (Amosite). White wavy with splayed ends (chrysotile) or blue, straight with splayed ends (crocidolite).
The only way to conclusively tell if a material is asbestos and its type is to collect and analyse it under a microscope using AS 4964—2004. The laboratory used must be NATA accredited for the method.
The two regulations specific to the discovery of asbestos in soil (NSW) are listed in the documents below:
Health screening levels are used when assessing the action required. They are taken from the National Environment Protection (Assessment of Site Contamination) Measure 1999 as amended and in force on 16 May 2013.
The health screening levels are assessed by collecting 500 mL of soil and sending them to a laboratory for asbestos concentration determination.
A risk assessment will need to be conducted on the material and that used to develop a management strategy. A management strategy may include one or more of the following:
Friable ACM is any material that contains more than one percent asbestos by weight or area, depending on whether it is a bulk or sheet material and can be crumbled, pulverized, or reduced to powder by the pressure of an ordinary human hand.
Bonded ACM are made from a bonding compound (such as cement) mixed with a small proportion (usually less than 15%) of asbestos. Bonded ACM are solid, rigid and non-friable, and cannot be crumbled, pulverised or reduced to powder by hand pressure. The asbestos fibres are tightly bound in the product and are not normally released into the air.
The results must be rejected. Depending on the time that the flow fault occurred, the results may still be useful in determining the asbestos air concentration.
If the building was constructed before 1987 there is a very good chance that it contains asbestos. But there is the possibility that a building constructed before December 2003 also contains asbestos.
An asbestos building register conducted by a licensed asbestos assessor will conclusively determine the location and type of asbestos present.
Most corrugated asbestos cement roof sheeting around NSW are old. They are fully exposed to the elements. As such many are deteriorating and leaking.
Often the upper surface of the roofing material is deteriorated, resulting in the release of loose fibres. These loose asbestos fibres can accumulate in lichen on the roof, in gutters or down pipes. This material is classed as friable and when it dries the fibres can become airborne.
Leaking asbestos cement roofs can allow drops of water, carrying asbestos fibres, onto the floor of your building. When the water dries the fibres can become airborne. All leaking asbestos roofs should be repaired or replaced promptly.
In general the use of water or gels (such as shaving cream) can help to reduce dust (note that wet methods cannot be used if there is an electrical hazard). Non-powered tools should be used as they make larger (less hazardous) dust particles than power tools. High speed abrasive power or pneumatic tools must not be used. Personal protective equipment and cleanup equipment is required
Asbestos fibres are often present on surfaces adjacent to bonded and friable asbestos products. It is near impossible to remove all asbestos fibres from surfaces adjacent to asbestos materials. Asbestos clearance for friable and bonded asbestos removal works involves the visual inspection of the surfaces for visible dust only.