Asbestos Wikipedia. Asbestos is a set of six naturally occurring silicate minerals,1 which all have in common their eponymousasbestiformhabit i. They are commonly known by their colors, as blue asbestos, brown asbestos, white asbestos, and green asbestos. Asbestos mining existed more than 4,0. Some of those properties are sound absorption, average tensile strength, affordability, and resistance to fire, heat, and electricity. It was used in such applications as electrical insulation for hotplate wiring and in building insulation. When asbestos is used for its resistance to fire or heat, the fibers are often mixed with cement or woven into fabric or mats. These desirable properties made asbestos very widely used. Asbestos use continued to grow through most of the 2. Prolonged inhalation of asbestos fibers can cause serious and fatal illnesses including lung cancer, mesothelioma, and asbestosis a type of pneumoconiosis. Concern of asbestos related illness in modern times began with the 2. By the 1. 98. 0s and 1. Despite the severity of asbestos related diseases, the material has extremely widespread use in many areas. Asbestos continuing long term use after harmful health effects were known or suspected, and the slow emergence of symptoms decades after exposure ceased, made asbestos litigation the longest, most expensive mass tort in U. The National Transportation Safety Board NTSB is an independent U. S. government investigative agency responsible for civil transportation accident investigation. AIB International GMP Inspection Results Report Consolidated Standards for Inspection Prerequisite and Food Safety Programs Contacts US Office. S. history and a much lesser legal issue in most other countries involved. Asbestos related liability also remains an ongoing concern for many manufacturers, insurers and reinsurers. EtymologyeditAsbestos derives from the ancient Greek, meaning unquenchable or inextinguishable. The word is pronounced, or. Types and associated fiberseditSix mineral types are defined by the United States Environmental Protection Agency EPA as asbestos including those belonging to the serpentine class and those belonging to the amphibole class. All six asbestos mineral types are known to be human carcinogens. The visible fibers are themselves each composed of millions of microscopic fibrils that can be released by abrasion and other processes. Chrysotile asbestos. Asbestos fibers. Asbestos. Asbestos. Blue asbestos, teased to show the fibrous nature of the mineral. SerpentineeditSerpentine class fibers are curly. Chrysotile is the only member of the serpentine class. ChrysotileeditChrysotile, CAS No. Its idealized chemical formula is Mg. Si. 2O5OH4. 1. Chrysotile appears under the microscope as a white fiber. Chrysotile has been used more than any other type and accounts for about 9. America. 1. 3 Chrysotile is more flexible than amphibole types of asbestos, and can be spun and woven into fabric. The most common use was corrugated asbestos cement roofing primarily for outbuildings, warehouses and garages. It may also be found in sheets or panels used for ceilings and sometimes for walls and floors. Chrysotile has been a component in joint compound and some plasters. Numerous other items have been made containing chrysotile including brake linings, fire barriers in fuseboxes, pipe insulation, floor tiles, residential shingles, and gaskets for high temperature equipment. AmphiboleeditAmphibole class fibers are needle like. Amosite, crocidolite, tremolite, anthophyllite and actinolite are members of the amphibole class. AmositeeditAmosite, CAS No. The official website of Science Olympiad, one of the largest K12 STEM organizations in the US. Find the latest info on events competitive tournaments here. Array of Aging American Aircraft Attracting Attention discusses the issues that accompany an air force whose fighters have an average age of over 23. South Africa, named as a partial acronym for Asbestos Mines of South Africa. One formula given for amosite is Fe. Image/1202103CoverStoryFig1.jpg' alt='Aib Chemical Control Program Example' title='Aib Chemical Control Program Example' />Si. O2. 2OH2. Amosite is seen under a microscope as a grey white vitreous fiber. It is found most frequently as a fire retardant in thermal insulation products, asbestos insulating board and ceiling tiles. CrocidoliteeditCrocidolite, CAS No. Africa, but also in Australia and Bolivia. One formula given for crocidolite is Na. Fe. 23. Fe. 32. Si. O2. 2OH2. Crocidolite is seen under a microscope as a blue fiber. Crocidolite 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 breadths less than 1 micrometer in bundles of very great widths. Asbestos with particularly fine fibers is also referred to as amianthus. Other materialseditOther regulated asbestos minerals, such as tremolite asbestos, CAS No. Ca. 2Mg. 5Si. 8O2. OH2 actinolite asbestos, CAS No. Ca. 2Mg, Fe5Si. O2. OH2 and anthophyllite asbestos, CAS No. Mg, Fe7. Si. 8O2. OH2 are less commonly used industrially but can still be found in a variety of construction materials and insulation materials and have been used in a few consumer products. Size of asbestos fibers compared to other particles USEPA, March 1. Concentration+Tests.jpg?format=500w' alt='Aib Chemical Control Program Example' title='Aib Chemical Control Program Example' />Other natural asbestiform minerals, such as richterite, NaCa. NaMg, Fe5Si. No more missed important software updates UpdateStar 11 lets you stay up to date and secure with the software on your computer. O2. 2OH2, and winchite, Ca. NaMg. 4Al, Fe. 3Si. O2. 2OH2, though not regulated, are said by some to be no less harmful than tremolite, amosite, or crocidolite. They are termed asbestiform rather than asbestos. Although the U. S. Occupational Safety and Health Administration OSHA has not included them in the asbestos standard, NIOSH and the American Thoracic Society have recommended them for inclusion as regulated materials because they may also be hazardous to health. ProductioneditIn 2. Canada. 1. 5 In late 2. Program Camfrog here. Canadas remaining two asbestos mines, both located in the Province of Quebec, halted operations. In September 2. 01. Province of Quebec halted asbestos mining. In 2. 01. 5, 2 million tonnes of asbestos were mined worldwide. The Russian Federation was the largest producer with about 5. China 2. 0, Brazil 1. Kazakhstan 1. 0. History of useeditEarly useseditAsbestos use dates back at least 4,5. Lake Juojrvi region in East Finland strengthened earthenware pots and cooking utensils with the asbestos mineral anthophyllite see Asbestos ceramic. One of the first descriptions of a material that may have been asbestos is in Theophrastus, On Stones, from around 3. BC, although this identification has been questioned. In both modern and ancient Greek, the usual name for the material known in English as asbestos is amiantos undefiled, pure, which was adapted into the French amiante and Portuguese amianto. In modern Greek, the word or stands consistently and solely for lime. The term asbestos is traceable to Roman naturalist Pliny the Elders manuscript Natural History, and his use of the term asbestinon, meaning unquenchable. While Pliny or his nephew Pliny the Younger is popularly credited with recognising the detrimental effects of asbestos on human beings,2. Wealthy Persians amazed guests by cleaning a cloth by exposing it to fire. For example, according to Tabari, one of the curious items belonging to Khosrow II Parviz, the great Sassanian king r. Persian that he cleaned simply by throwing it into fire. Such cloth is believed to have been made of asbestos imported over the Hindu Kush. According to Biruni in his book, Gems, any cloths made of asbestos Persian, zarshost were called shostakeh Persian. Some Persians believed the fiber was the fur of an animal, called the samandar Persian, which lived in fire and died when exposed to water,2. Charlemagne, the first Holy Roman Emperor 8.