Asbestos – Definition
Asbestos – a fibrous amphibole; used for making fireproof articles; inhaling fibers can cause asbestosis or lung cancer.
Amphibole – a mineral or mineral variety belonging to the amphibole group.
Chrysotile – a gray or green fibrous mineral; an important source of commercial asbestos.
Tremolite – a white or pale green mineral (calcium magnesium silicate) of the amphibole group used as a form of asbestos.
Asbestos is a family of naturally occurring minerals, found in serpentinite and other metamorphic rock.
Because of its strength and resistance to heat, asbestos was used for insulation, heat-resistant clothing, roofing, and fireproofing. It was also used as an additive to ease the manufacture and application of ceiling and wall finishes, tape joint compounds, floor tiles, and mastics.
Since many building materials can contain asbestos, remodel and repair activity in residential and commercial structures which disturbs asbestos-containing materials may cause the release of asbestos fibers into the air. There is no known health threat if asbestos-containing materials are in generally good condition and are left undisturbed.
Inhaling airborne asbestos fibers can increase the risk of developing certain lung diseases, including lung cancer, mesothelioma, and asbestosis.
In the United States, there are many regulations protecting children, employees, tenants, workers, and others from asbestos exposure. These include AHERA (schools), OHSA (workers), ASHARA (public buildings), and NESHAPS (emissions).
Types of Asbestos
There are two types of asbestos-containing material:
Friable Asbestos-Containing Materials – contain over 1% asbestos and can be crumbled, crushed, or reduced to powder by hand pressure when dry. Common examples of friable asbestos-containing materials are spray acoustic ceilings, acoustic tiles, plaster, pipe and duct wrap, and paper backing of linoleum.
Non-friable Asbestos-Containing Materials – are typically bound up with cement, vinyl, asphalt, or some other type of hard binder. Some examples of non-friable asbestos building materials are cement/transite siding, vinyl floor tiles, and stucco. Non-friable asbestos-containing material may become friable if it is crushed, crumbled, pulverized, or subjected to sanding, drilling, grinding, cutting, or abrading.