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]] . The ruler is 1 cm. ]] The word Asbestos is derived from a , Canada , Brazil , Zimbabwe , and South Africa . Russia is also indicated in its production. The Greeks termed asbestos the "miracle mineral" as they admired it for its soft and pliant properties, as well as its ability to withstand heat. Asbestos was spun and woven into cloth in the same manner as cotton. It was also utilized for wicks in sacred lamps. Romans likewise recognized the properties of asbestos and it is thought that they cleaned asbestos tablecloths by throwing them into the flames of fire. Asbestos became increasingly popular to manufacturers and builders in the late 1800s due to its heat resistance, electrical resistance, sound absorbing, tensile strength and chemical resistant properties. When asbestos is used for its resistance to fire or heat, the fibers are often mixed with Cement or woven into fabric or mats. Asbestos is used in Brake shoes and Gasket s for its heat resistance, and in the past was used on electric oven and hotplate wiring for its Electrical Insulation at elevated temperature, and in buildings for its Flame-retardant and insulating properties, Tensile Strength , flexibility, and resistance to chemicals. The Inhalation of Asbestos Fibers can cause serious illnesses, including Mesothelioma . Since the mid 1980s, many uses of asbestos are banned in multiple countries. TYPES OF ASBESTOS AND ASSOCIATED FIBRES Six minerals are defined as "asbestos" including: Chrysotile , Amosite , Crocidolite , Tremolite , Anthophyllite and Actinolite . White asbestos . It is more flexible than amphibole types of asbestos; it can be spun and woven into Fabric . Chrysotile, like all other forms of industrial asbestos, has produced tumors in animals. Mesothelioma s have been observed in people who were occupationally exposed to chrysotile, family members of the occupationally exposed, and residents who lived close to asbestos factories and mines. American Cancer Society Brown asbestos Amosite , CAS No. 12172-73-5, is a Trade Name for the Amphibole s belonging to the '' Cummingtonite '' - ''Grunerite'' Solid Solution series, commonly from Africa , named as an Acronym from Asbestos Mines of South Africa. One formula given for amosite is Fe 7Si8O22(OH)2. It is found most frequently as a fire retardant in thermal insulation products and ceiling tiles. This type of asbestos, like all asbestos, is very hazardous. Blue asbestos Crocidolite , CAS No. 12001-28-4 is an amphibole from Africa and Australia . It is the fibrous form of the amphibole riebeckite. Blue asbestos is commonly thought of as the most dangerous type of asbestos (see above and below). One formula given for crocidolite is Na 2Fe2+3Fe3+2Si8O22(OH)2. This type of asbestos is very hazardous. Notes: chrysotile commonly occurs as soft friable Fibers . Asbestiform amphibole may also occur as soft friable fibers but some varieties such as amosite are commonly straighter. All forms of asbestos are fibrillar in that they are composed of fibers with widths less than 1 Micrometre that occur in bundles and have very long lengths. Asbestos with particularly fine fibers is also referred to as "amianthus". Amphiboles such as tremolite have a sheetlike Crystalline Structure . Serpentine (chrysotile) has a stringlike crystalline structure.1 Tremolite often comtaminates chrysotile asbestos, thus creating an additional hazard. Other asbestos Other regulated asbestos minerals, such as tremolite asbestos, CAS No. 77536-68-6, Ca 2Mg5Si8O22(OH)2; actinolite asbestos (or ''smaragdite''), CAS No. 77536-66-4, Ca2(Mg, Fe)5(Si8O22)(OH)2; and anthophyllite asbestos, CAS No. 77536-67-5, (Mg, Fe)7Si8O22(OH)2; are less commonly used industrially but can still be found in a variety of construction materials and insulation materials and have been reported in the past to occur in a few Consumer Products . Other natural and not currently regulated asbestiform minerals, such as richterite, Na(CaNa)(Mg,Fe++)5(Si8O22)(OH)2, and winchite, (CaNa)Mg4(Al,Fe3+)(Si8O22)(OH)2, may be found as a contaminant in products such as the Vermiculite containing Zonolite insulation manufactured by W.R. Grace And Company . These minerals are thought to be no less harmful than tremolite, amosite, or crocidolite, but since they are not regulated, they are referred to as "asbestiform" rather than asbestos although may still be related to diseases and hazardous. In 1989 the United States Environmental Protection Agency (EPA) issued the Asbestos Ban and Phase Out Rule which was subsequently overturned in the case of Corrosion Proof Fittings v. U.S. Environmental Protection Agency, 1991. This ruling leaves many consumer products that can still legally contain trace amounts of asbestos. For a clarification of products which legally contain asbestos visit the EPA's clarification statement. EPA clarification statement on asbestos (PDF format) PRODUCTION TRENDS | ||||||||||||||||||||||||||||||||||||||||||||||||
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