What are the historical uses of asbestos?
Asbestos is the fibrous form of mineral silicates belonging to the serpentine and amphibole groups of rock-forming minerals.
The most common form of asbestos used in Australia is crocidolite (blue asbestos), and chrysotile (white asbestos). Crocidolite and chrysotile account for over 95% of asbestos based materials used in Australia. Other mineral forms of asbestos were not widely used.
As a naturally occurring mineral fibre, asbestos is mined and then broken down from mineral clumps into groups of loose fibres.
Asbestos has excellent fire resistance, insulation properties, fibre strength, durability and flexibility. As a result, it was used in more than 3,000 products, including heat-resistant textiles (cloth, padding and board), asbestos cement products (sheets and pipes), special filters for industrial chemicals, thermal insulation products (pipe and boiler insulation), friction materials (clutch plates, brake linings), gaskets, floor tiles, roofing materials, packing materials, paints and protective paper.
A major historical use was as sprayed thermal insulation on steel beams for fire protection. This sprayed or ‘limpet’ asbestos poses the greatest health risk, because of its highly friable nature.
Asbestos-containing materials (ACM) may still be encountered throughout public and private buildings and structures, especially those built between the 1950s and the late 1970s to early 1980s. Some uses of ACM continued until 2003, notably in friction materials (brakes) and gaskets.
Asbestos training courses are available online.