Asbestos is the generic term used for a number of silicate minerals with fibrous crystalline structures. For more than 4,500 years naturally occurring fibrous minerals have been used by humans for their flexibility, strength, chemical inertness and insulation qualities. The Romans used asbestos for its flame-retardant and insulation properties by weaving asbestos fibers into fabrics and the Ancient Egyptians also used asbestos to improve durability in their clothes.
The Greeks first coined the term asbestos, meaning ‘inextinguishable’. Greek ‘a’ means ‘not’ and ‘sbestos’ means ‘extinguishable’. There are many historical references to the use of asbestos through-out history including a well known story of the Roman Emperor Charlemagne, who reportedly threw a tablecloth into a fire and pulled it out without a mark on it to demonstrate his supernatural powers to guests.
During the reign of Peter the Great, in the 1700s, asbestos was discovered in the Ural Mountains, Russia, and the first factory for manufacturing asbestos products began. Asbestos originated on a commercial scale in Italy at the beginning of the 19th Century. In Canada mining of white asbestos (chrysotile) started in 1878. Blue asbestos (crocidolite) was discovered in South Africa in 1815 and the first crocidolite mines opened near Prieska in 1893. The name ‘crocidolite’ means a stone with a woolly appearance. Amosite (brown asbestos) was discovered in Transvaal, South Africa, and the name was derived from the initials of theAsbestos Mines of South Africa.
The asbestos minerals belong to two distinct mineralogical groups:
- Serpentine including: chrysotile (white asbestos), and
Amphibole including: amosite (brown asbestos) and crocidolite (blue asbestos), as well as a number of less known types such as tremolite, actinolite and anthophyllite.
The distinction between these two groups is important when it comes to asbestos-related diseases. Asbestos fibres are up to 200 times thinner than a human hair. The amphibole fibres are thin and straight and the serpentine are curved fibres.
Asbestos in Australia
Asbestos was mined in NSW from 1940-1979 at Baryulgil on the north coast, at Barraba on the northern tablelands from 1918–23 and 1970–83 and at Wittenoom in Western Australia from 1940-1966.
The widespread use of asbestos during the last century in manufacturing, transport, and building products (particularly sheeting and roofing) has resulted in an increasing number of people developing asbestos-related diseases. Products containing asbestos can still be found widely in the community, they include:
- Asbestos cement sheet pipe and products used for water supply and sewage piping, casings for electrical wires, fire protection material, chemical tanks, electrical switchboards and residential and industrial building materials such as cement sheeting.
- Friction products such as clutch facings and brake linings for cars.
- Products containing asbestos paper such as table pads and heat protective mats, heat and electrical wire insulation, small appliance components and underlying material for sheet flooring.
- Asbestos textile products such as packing components, roofing materials, heaters.
- Other products including ceiling and floor tiles, gaskets and packing, paints, coating and sealants.
Asbestos products were gradually removed from production during the 1980s. Between 1981 and 1983, asbestos flat sheeting was phased out. In 1985, corrugated products (roofing and cladding) were also removed from production. Asbestos-lined piping was not made after 1987 and in 2003 brake pads and linings ceased to contain asbestos.
Legislation in Australia makes it illegal for any new materials to contain asbestos fibres and people are no longer able to import, manufacture, supply, store, transport, sell, use, reuse, install or replace asbestos-containing materials.
Despite an Australia wide ban on asbestos being sold, reused and/or imported into Australia after 31 December 2003, some asbestos materials have been imported into the country, accordingly if you have concerns about a product or material; have it tested by a National Association of Testing Authorities (NATA) accredited laboratory – www.nata.asn.au