What Is Asbestos?
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 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 There are many historical references to the use of asbestos throughout history including a well-known story of the Roman Emperor Charlemagne, who reportedly threw a tablecloth into a fire and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 the Asbestos 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.
Naturally Occurring Asbestos
Naturally Occurring Asbestos (NOA) is found in some rocks, sediments, and in soils and is not easy to identify. A sample collected by a competent person can be tested by a National Association of Testing (NATA) accredited laboratory to confirm the presence of asbestos in its natural form. Less than one percent of land in NSW is believed to contain NOA within 10 metres of the grounds surface. In rural and regional NSW where NOA is known, or suspected, property owners, managers, workers, and the general public who may disturb the ground surface will need to take appropriate precautions to ensure NOA is identified and managed safely in accordance with regulations.
See Asbestos Awareness for information on NOA Management Plan.