The term asbestos comes from the Greek word for “inextinguishable” or “indestructible.” Asbestos is a fibrous mineral with thermal and chemical resistance, flexibility, and high tensile strength properties. Although its use has been reduced since the 1970's, today asbestos is still present in many common household items and old buildings.
The first use of asbestos dates back to 2500 B.C., when it was used as a wick material for oil lamps and also in pottery making. Asbestos was also used in cloths for retaining the ashes of the dead during cremation. Mats were also made from asbestos by both the Chinese and Egyptians. Combining asbestos with clay and other materials was also one of its earlier applications.
Asbestos is classified into many different types, which include; chrysotile (white asbestos), crocidolite (blue asbestos), amosite (brown asbestos), tremolite, anthopyllite, and actinolite.
However, only chrysolite is the most widely used asbestos type in the United States. Other asbestos types used commercially are crocidolite and amosite, but in a limited capacity. Tremolite, anthopyllite, and actinolite are the most abundant, but they have been used primarily as contaminants of other minerals, such as chrysotile, verniculite, and talc.
Since its discovery, asbestos has found widespread use in part due to its unmatched engineering and commercial performance. Due to its thermal resistant qualities, asbestos has been used as a frictional material in break pads. It has also been used in specialized products such as gaskets, pads, fabric sheets, and asbestos paper due to the length and pliability of its fibers. Mixed into a slurry, asbestos has been applied to building surfaces for fire protection and heat retention, such as in furnaces and kilns. As a fortifying additive, which is it's major present day use, asbestos is a component of cement, concrete, paint, vinyl, and tar mixtures, accounting for 70% of current applications worldwide.
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