What is asbestos?
Asbestos is the name of a group of minerals that occur naturally in the environment as bundles of fibers that can be separated into thin, durable threads.
These fibers are resistant to heat, fire, and chemicals, and no driver. For these reasons, asbestos was widely used in many industries.
Chemically, the silicate minerals are asbestos-containing compound of silicon and oxygen atoms in its molecular structure.
Asbestos minerals are divided into two main groups: serpentine asbestos and amphibole asbestos. Containing serpentine minerals chrysotile asbestos, which has long, curly fibers, which can be woven. Chrysotile asbestos is a form that is widely used for commercial purposes. Amphibole asbestos minerals include actinolite, tremolite, anthophyllite, amosite and crocidolite. Amphibole asbestos straight, needle-type fibers, which are more fragile than serpentine asbestos and are more limited in their ability to produce.
How to use asbestos?
Asbestos was mined and used commercially in North America since late 1800. Increased their use during World War II . Since that time, asbestos was used in many industries. For example, in building and construction industry is used to strengthen cement and plastics, and insulation, roofing, fire protection and sound absorption.
In the shipbuilding industry used asbestos to insulate boilers, steam and hot water pipes. In the automotive industry uses asbestos in vehicle brake shoes and clutch pads. Asbestos was used in the ceiling and floor tiles, paints, coatings and adhesives, and plastics. Additionally, asbestos is found in the vermiculite, and garden products containing talc-containing crayons.
In late 1970, the U. S. Consumer Product Safety Commission (CPSC) banned the use of asbestos in the correction of compound wall and gas fireplaces because the asbestos fibers in these products can be released into the environment during use. In addition, manufacturers of electric hairdryers voluntarily stopped using asbestos in their products in 1979.
In 1989, the U. S. Environmental Protection Agency (EPA) banned all new uses of asbestos, but uses established prior to 1989 are still allowed. The EPA established regulations that require school systems to check the damage to the building of asbestos and to eliminate or reduce exposure to asbestos at the residents by removing the asbestos or encasing.
In June 2000, the CPSC concluded that the risk of childhood exposure to asbestos fibers in the smaller is very low. However, U.S. manufacturers these crayons agreed to eliminate talc from their products.
In August 2000, EPA conducted a series of tests to assess the risk to consumers from the adverse health effects associated with exposure to asbestos-contaminated vermiculite. The EPA concluded that exposure to asbestos in vermiculite products poses only a minimal health risk.
The EPA recommends that consumers reduce the risk associated with low occasional use of vermiculite in gardening activities by limiting the amount of dust in the use of vermiculite. In particular, the EPA suggests consumers use vermiculite outdoors or in well-ventilated place, keep moist vermiculite, and use it to avoid the dust of vermiculite in the house on clothing, but also uses pre-tension of land, which is less likely that the powder.
The rules described above, and other actions, coupled with widespread concerns about the health risks of asbestos, have resulted in a significant annual decline in U.S. the use of asbestos. Domestic consumption of asbestos amounted to about 803,000 tons in 1973, but fell to 2,400 metric tons in 2005.
These fibers are resistant to heat, fire, and chemicals, and no driver. For these reasons, asbestos was widely used in many industries.
Chemically, the silicate minerals are asbestos-containing compound of silicon and oxygen atoms in its molecular structure.
Asbestos minerals are divided into two main groups: serpentine asbestos and amphibole asbestos. Containing serpentine minerals chrysotile asbestos, which has long, curly fibers, which can be woven. Chrysotile asbestos is a form that is widely used for commercial purposes. Amphibole asbestos minerals include actinolite, tremolite, anthophyllite, amosite and crocidolite. Amphibole asbestos straight, needle-type fibers, which are more fragile than serpentine asbestos and are more limited in their ability to produce.
How to use asbestos?
Asbestos was mined and used commercially in North America since late 1800. Increased their use during World War II . Since that time, asbestos was used in many industries. For example, in building and construction industry is used to strengthen cement and plastics, and insulation, roofing, fire protection and sound absorption.
In the shipbuilding industry used asbestos to insulate boilers, steam and hot water pipes. In the automotive industry uses asbestos in vehicle brake shoes and clutch pads. Asbestos was used in the ceiling and floor tiles, paints, coatings and adhesives, and plastics. Additionally, asbestos is found in the vermiculite, and garden products containing talc-containing crayons.
In late 1970, the U. S. Consumer Product Safety Commission (CPSC) banned the use of asbestos in the correction of compound wall and gas fireplaces because the asbestos fibers in these products can be released into the environment during use. In addition, manufacturers of electric hairdryers voluntarily stopped using asbestos in their products in 1979.
In 1989, the U. S. Environmental Protection Agency (EPA) banned all new uses of asbestos, but uses established prior to 1989 are still allowed. The EPA established regulations that require school systems to check the damage to the building of asbestos and to eliminate or reduce exposure to asbestos at the residents by removing the asbestos or encasing.
In June 2000, the CPSC concluded that the risk of childhood exposure to asbestos fibers in the smaller is very low. However, U.S. manufacturers these crayons agreed to eliminate talc from their products.
In August 2000, EPA conducted a series of tests to assess the risk to consumers from the adverse health effects associated with exposure to asbestos-contaminated vermiculite. The EPA concluded that exposure to asbestos in vermiculite products poses only a minimal health risk.
The EPA recommends that consumers reduce the risk associated with low occasional use of vermiculite in gardening activities by limiting the amount of dust in the use of vermiculite. In particular, the EPA suggests consumers use vermiculite outdoors or in well-ventilated place, keep moist vermiculite, and use it to avoid the dust of vermiculite in the house on clothing, but also uses pre-tension of land, which is less likely that the powder.
The rules described above, and other actions, coupled with widespread concerns about the health risks of asbestos, have resulted in a significant annual decline in U.S. the use of asbestos. Domestic consumption of asbestos amounted to about 803,000 tons in 1973, but fell to 2,400 metric tons in 2005.
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