Asbestos is the name for a group of naturally occurring silicate minerals that can be separated into fibers. The fibers are strong, durable, and resistant to heat and fire. Asbestos materials are also long, thin and flexible, so that they can even be woven into cloth.
Because of these qualities, asbestos has been used in thousands of consumer, industrial, maritime, automotive, scientific and building products. During the twentieth century, some 30 million tons of asbestos were used in industrial sites, homes, schools, shipyards and commercial buildings in the United States.
There are several types of asbestos fibers, of which three have been used for commercial applications: (1) Chrysotile, or white asbestos, comes mainly from Canada, and has been very widely used in the US. It is white-gray in color and found in serpentine rock. (2) Amosite, or brown asbestos, comes from southern Africa. (3) Crocidolite, or blue asbestos, comes from southern Africa and Australia.
Amosite asbestos and crocidolite asbestos materials are called amphiboles. This term refers to the nature of their geologic formation.
Other asbestos fibers that have not been used commercially are tremolite asbestos, actinolite asbestos and anthophyllite asbestos, although these materials are sometimes contaminants in asbestos-containing products. It should be noted that there are non-fibrous, or non-asbestiform, variants of tremolite, anthophylite and actinolite, which do not have the adverse health consequences that result from exposure to commercial forms of asbestos.
What are asbestos-containing products?
What is common to many asbestos-containing products is that they were (are) used to contain heat (i.e. thermal insulation.) It is impossible to list all of the products that have, at one time or another, contained asbestos. Some of the more common asbestos-containing products are pipe-covering, insulating cement, insulating block, asbestos cloth, gaskets, packing materials, thermal seals, refractory and boiler insulation materials, transite board, asbestos cement pipe, fireproofing spray, joint compound, vinyl floor tile, ceiling tile, mastics, adhesives, coatings, acoustical textures, duct insulation for heating, ventilation and air conditioning (HVAC) systems, roofing products, insulated electrical wire and panels, and brake and clutch assemblies.
Some of these products contained a very high proportion of asbestos, while others contained small amounts.
Since asbestos causes many diseases like malignant mesothelioma, pleural mesothelioma, peritonial mesothelioma. People are suggested to be aware of this asbestos and its usage. Of these mesothelioma asbestos diseases is effecting when a person is highly exposed to asbestos.
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Sources of National Cancer Institute Information