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Asbestos - What It Is And How It's Used |
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Asbestos - What It Is And How It's UsedBy Michael Russell Asbestos isn't actually one thing. It is a name given to a group of minerals. These minerals occur naturally in bundles of fibers that can be separated into thin threads. These fibers are completely resistant to heat and any kind of chemical and do not conduct electricity. Because of these attributes asbestos is has been used in many industries. There are basically four types of asbestos that are used. 1. Chrysotile, or white asbestos 2. Crocidolite, or blue asbestos 3. Amosite, which usually has brown fibers 4. Anthophyllite, which usually has gray fibers The problem with asbestos fibers is that they tend to break very easily and the dust made up of these fibers floats into the air and gets on our clothes and in our lungs. When this happens serious health problems can occur. Asbestos was first mined and commercially used in the United States in the late 1800s. During the second world war its use increased dramatically. Since then it has been used in many industries. To give some examples, the building and construction industry uses it to strengthen cement and plastics. They also use it for insulation, fireproofing and sound absorption. The shipbuilding industry uses asbestos to insulate boilers, steam pipes and hot water pipes. The automobile industry uses it in its brake shoes and clutch pads. There are over 5000 products that contain asbestos including sewage piping, roofing and siding, electric switchboards, table pads, heat protective mats, heat resistant blankets and curtains, paints, adhesives, caulking, and the list goes on and on. But when the dangers of asbestos became known in the 1970s the U.S. Consumer Product Safety Commission (CPSC) banned the use of asbestos in wallboard patching compounds and gas fireplaces because the asbestos fibers in these products could be released into the air from its use. Also during that time, asbestos was removed from electric hair dryers. In 1989 the EPA finally banned all new uses of asbestos. Uses prior to 1989, however, are still allowed. Since that time, the EPA has established regulations that require school systems to inspect for asbestos that has been damaged in order to eliminate, or at least reduce, the exposure to students and faculty, by removing the damaged areas. In the year 2000 the EPA concluded that the current risk to children from asbestos in schools was very low, however, it was agreed that their products would have to be reformulated within a year. By August of that same year products were being made that greatly reduced the amount of dust that was released during use. The amount of metric tons of asbestos generated in a year dropped from 719,000 metric tons in 1973 to only 9000 metric tons by the year 2000. In the next instalment we'll go over the health risks from exposure to asbestos.
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