What is Asbestos?
Asbestos is a naturally occurring mineral found in the surface of the earth. It contains strong fibres that have excellent durability, fire resistance and insulating properties. Materials containing asbestos were very common in the Australian residential building industry between the 1940s and late 1980s before their production stopped due to their negative and lethal health implications. The use of all forms of asbestos has been banned nationally since 31 December 2003.
What is ACM?
ACM stands for Asbestos Containing Materials, there are two types:
- Friable Asbestos Containing Materials (ACM): They were primarily used in commercial and industrial settings for fireproofing, soundproofing and insulation. However, they can be found in some old domestic heaters, stoves, hot water systems and associated pipe lagging and in the backing of vinyl and linoleum floor coverings. These materials can be made of up to 100% asbestos. They are quite loose and can be turned to dust with very light pressure, such as crushing with your hand. They are the most dangerous type of ACM, as the fibres become airborne and inhaled.
- Non-friable ACM: They are mainly made up of a bonding compound (such as cement), with up to 15% asbestos. Bonded materials containing asbestos are solid, quite rigid and the asbestos fibres are tightly bound in the material. E.g., fibro sheeting, sealants, asbestos cement, AC sheeting, etc. If damaged, the fibres can be released and potentially become airborne.
What are the types and where were they used commercially?
- Chrysotile is the most commonly used form of asbestos. It can be found today in the roofs, ceilings, walls and floors of homes and businesses.
- Amosite was used most frequently in cement sheets and pipe insulation. It can also be found in insulating boards, ceiling tiles and thermal insulation products.
- Crocidolite was commonly used to insulate steam engines. It was also used in some spray-on coatings, pipe insulation, plastics and cement products.
- Anthophyllite was used in limited quantities for insulation products and construction materials. It also occurs as a contaminant in chrysotile asbestos, vermiculite and talc. It may have a grey, dull green or white colour.
- Tremolite and Actinolite are not used commercially, but they can be found as contaminants in chrysotile asbestos, vermiculite and talc. These two chemically similar minerals can be brown, white, green, grey or transparent.
As a part of Asbestos Awareness Month, Archi-QS are doing our part in educating our industry peers with the knowledge they need to identify and work safely with asbestos or asbestos containing material.
King, D. 2019. ‘Types of Asbestos’ < https://www.asbestos.com/asbestos/types/