Asbestos is the name given to a group of naturally occurring fibrous silicate minerals found in rock formations that were mined in Australia and overseas. It was used predominantly in building materials (such as asbestos cement) but it was also used in motor vehicles (such as brake pads).
Asbestos fibres were widely used because of their unique chemical and physical properties. They could protect against fire, corrosion, cold, acids, alkalis, electricity, noise, energy loss, vibration, salt water, frost, dust and even vermin. Asbestos also has excellent friction and wear resistance, and so was used extensively in brake linings and clutch facings.
All forms of asbestos were banned in Australia from 31 December 2003. From this date any work with asbestos or asbestos-containing materials must be conducted in line with legislation, including the
- disposal, and
- disturbance of asbestos.
Asbestos-containing materials were commonly used in building materials up until the mid-1980s. As a general rule if your house or workplace was built or renovated:
- before the mid-1980s - it is highly likely that it has asbestos-containing products
- between the mid-1980s and 1990 - it is likely that it has asbestos-containing products
- after 1990 - it is unlikely that it has asbestos-containing products.
Asbestos fibres are strong, heat resistant and have insulating properties. Asbestos-containing building products are classified as either friable (soft, crumbly or loose fibres) or non-friable (bonded or solid). Asbestos does not dissolve in water and does not break down and therefore remains virtually unchanged over long periods.
Non-friable asbestos is generally safe and does not easily release fibres, as long as it remains undisturbed and in good condition.
Non-friable asbestos products are made with a bonding compound (such as cement) mixed with a small amount of asbestos so that the fibres are tightly bound in the product. These products are solid or rigid and cannot be crumbled by hand pressure and therefore the fibres are not normally released into the air. However, products may become friable if they are damaged or badly weathered.
Non-friable asbestos products are considered a very low risk for people who are in contact with them as long as safety precautions are used when materials are disturbed.
Friable asbestos products have been commonly used in commercial and industrial settings since the late 1800's for fireproofing, soundproofing and insulation. Some friable products were also used in houses and may still be found in houses built before 1990.
Friable asbestos products contain loosely bound fibres and, when dry, can be very brittle and crumble with light pressure. Because of its brittle nature, friable asbestos is more hazardous than non-friable asbestos as fibres are more easily released. The fibres are not visible to the naked eye. They are very fine and can stay in the air for long periods or can be carried by the wind over large distances. Research has shown that asbestos fibres are dangerous if inhaled.
Friable asbestos material should only be removed by a Class A licensed asbestos removalist.
Types of asbestos containing materials
Products that include asbestos are known as an asbestos-containing materials.
- asbestos cement roofing (sheets and shingles)
- asbestos cement wall cladding, including ‘brick look’ wall cladding
- asbestos cement fencing
- moulded products such as flues, downpipes, guttering, ridge capping and water pipes
- gable ends and lining under eaves
- asbestos cement wall linings and ceiling linings
- splashbacks and backing to wall tiles
- flooring such as vinyl floor tiles and asbestos backed sheets
- underlay sheeting for ceramic tiles and carpet underlay
- insulation in wood heaters and sheeting beneath wood heater hearths
- insulation to some air-conditioning heating banks
- flues to fireplaces and fireplace surrounds
- loose fill insulation in roof cavity
- sealants, gaskets, adhesives and filters
- brake pads, clutch components and other friction products
- textiles such as oven gloves, ironing surfaces, insulating mats, felts, ropes, fire blankets and woven asbestos cable sheathing
- rubber, plastic and paint products (particularly industrial), epoxy paints
- sprayed insulation materials used for fire-proofing, thermal protection, insulation and sound-proofing
- lagging and insulation materials used in a wide range of electrical, thermal and acoustic settings, including backing for electrical meter boards and ovens.