Asbestos materials

Optical microscope asbestos reference standards for use in identifying and quantifying asbestos types are available both from NIST and the Institute of Occupational Medicine flOM) in Edinburgh, Scotland. The lOM materials consists of various asbestos materials actinolite, amosite, anthophyUite, chrysotile (both from Cassiar, Canada and Zimbabwe), crocidolite and tremoUte. 

The NIST material SRM 1866a consists of a set of three common bulk mine-grade asbestos materials chrysotile, amosite and crocidolite, and one glass filter sample. SRM 1867 consists of a set of three imcommon mine-grade asbestos materials antophyllite, tremolite and actinohte. The optical properties of SRMs 1866a and 1867 have been characterized so that they may serve as primary calibration standards for the identification of asbestos types in building materials. 

SRM 1868 consists of a set of two common bulk mine-grade asbestos materials chrysotile and amosite, contained in matrices simulating building materials (calcium carbonate and glass fiber), in quantities at just below the U.S. ERA regulatory limit of I %. This material is certified by weight for the quantity of each asbestos material present. 

Asbestos. EPA issued a proposed rule concerning identification and correction of friable asbestos-containing materials in schools. Based on data voluntarily submitted, EPA estimated that at least 8,600 public schools attended by over 3 million children contain such materials. However, EPA reportedly has no information on another 44,000 schools. Classroom concentrations of asbestos fibers in some schools have been found to approximate concentrations in homes of asbestos workers who do not have shower or laundry facilities at work. Since children exposed to asbestos will live long enough to allow the cancer latency period to elapse, the presence of friable asbestos materials in schools represents a potentially enormous public health problem. The final asbestos rule will reportedly be promulgated in the near future. (The rule was published May 27, 1982.) No other regulations regarding asbestos have been issued. 

Fiber has been given a legal, if not operational definition, at least as it applies to asbestos. Unfortunately tlie definition bears little relationship to the present use of the term. It was essential to set standards to reduce occupational exposure but the detection, identification, and suppression of asbestos materials opened several areas of problems that remain unsolved. For example, six minerals are included in the definition of asbestos. Are they all equally hazardous If not, why not There are many other inorganic particles with diameters of less than 3 micrometers and a diameter-to-length ratio of 1 3. Should we be concerned that they too might be hazardous to our health ... 

The Greek a-mianto was also used to refer to asbestos materials. The... 

Some asbestos materials can break into small fibers that can float in the air, and these fibers can be inhaled. These tiny fibers are small, cannot be seen, and can pass through the filters of normal vacuum cleaners and get back into the air. Once inhaled, asbestos fibers can become lodged in tissue for a long time. After many years, cancer or other sickness can develop. In order to be a health risk, asbestos fibers must be released from the material and be present in the air for people to breathe. A health risk exists only when asbestos fibers are released from the material or product. Soft, easily crumbled asbestos-containing material, previously defined as friable asbestos, has the greatest potential for asbestos release and therefore has the greatest potential to create health risks. 

During the removal of asbestos-containing material, workers should wear approved respirators appropriate for the specific asbestos activity. Workers should also wear gloves, hats, and other protective clothing. The contractor should properly dispose of all of this equipment (along with the asbestos material) immediately after using it. 

Specific regulations exist for the transport of asbestos materials by highway [53]. Asbestos must be loaded, handled, and unloaded using procedures that minimize occupational exposure to airborne asbestos particles released in association with transportation. Any asbestos contamination of transport vehicles also must be removed using such procedures (49 CFR 177.844). Additional motor carrier s safely regulations apply to common, contract, and private carriers of property by motor vehicle, as defined under these regulations (49 CFR Parts 390-397). 

Ward Scientific Company (16) sells mineral specimens including asbestos. The National Institute of Environmental Health Sciences, (NIEHS) (17) supplies asbestos materials that have been characterized. UnTo n Internationale Contre Cancer (UICC) asbestos materials, often used in cancer research, are obtainable in laboratory quantity from Walter C. McCrone Associates, Inc. (18). 

Soil may be contaminated with asbestos by the weathering of natural asbestos deposits, or by land-based disposal of waste asbestos materials. While disposal of waste asbestos to landfills was a common practice in the past, current regulations restrict this practice (see Chapters 5 and 8). 

Strokova B, Evstatieva S, Dimitrova S, et al. 1998. Study of asbestos exposure in some applications of asbestos materials in the chemical industry. Int Arch Occup Environ Health 71(Suppl.) 19-21. 

Typical concentrations of asbestos fibers (with lengths 5 m) in urban and rural ambient air may be about 0.0001 or 0.00001 fiber/mL, respectively (ATSDR 2001a). In workplace air, recent U.S. regulations have limited asbestos air concentrations to 0.1 to 0.2 fiber/mL to protect against the development of pulmonary fibrosis and cancer (OSHA 1992, 1994). A study of indoor air of homes, schools, and other buildings that contain asbestos materials measured an average asbestos concentration of about 0.0001 fiber/mL (Lee et al. 1992). Most of the fibers in this study were identified as chrysotile 2%... 

EPA (1999b). EPA Asbestos Materials Bans Clarification. US Environmental Protection Agency, Washington, D.C. Accessed at http //www.epa.gov/asbestos/pubs/asbbans2.pdf. 

The health effects of long term or high levels of exposure to airborne asbestos fibres have been well documented since the early 1900s and were reported by the medical profession on many occasions in the first half of the last century. The majority of illnesses that are occurring at the present time are due to exposure forty to fifty years ago during the peak usage and manufacture of asbestos materials for the construction industry. These illnesses include the following fatal diseases ... 

At present, there is no official guidance defining what percentage of asbestos in soil would constitute a health risk and how this figure might depend upon the asbestos type, product, material, friability or moisture content etc. However, the UK HSE is also reviewing the test methods for asbestos materials in contaminated land and may provide additional guidance as part of this future documentation. 

In accordance with the Federal Toxic Substance Control Act, the EPA is to be reported at least 10 days before any asbestos abatement project that contains >1% by weight of friable asbestos material in an area of >3 ft (linear) or 3 ft. Flooding, fire, or any other emergency projects are to be reported 48 hours after the project begins (U.S. EPA... 

Friable Asbestos Materials materials that contain more than one percent asbestos by weight and that can, by hand pressure, be crumbled, pulverized, or reduced to powder, thus allowing for potential release of asbestos fibers into the air. 

Reportable Excess Property excess property that is reportable to the GSA by the holding agency (see definition) on Standard Form 120, excluding Hazardous Waste (see definition). Extremely Hazardous Property (see definition). Scrap (see definition). Controlled substances. Chemicals determined to be appropriate for abandonment or destruction. Nuclear-related and Proliferation-sensitive Property (see definition). National security-sensitive property, NRC-controlled materials, etc. Reportable excess property includes non-hazardous chemicals, drugs and reagents other than controlled substances nonifiable asbestos materials, excluded PCB products (i.e., those containing less than 49 ppm PCBs), etc.. 

Note that the compressibility and compression set are also recorded in this test. The upper curve shown on Fig. 1 refers to the commercial SBR-asbestos material now used for most Saturn LOX gasketing applications. This product is marginal in its sealing properties and requires elaborate pretreatment with a chlorofluorocarbon polymer oil to minimize its potential reactivity with liquid oxygen. 

The only way to determine if a material contains asbestos is to have it tested and analyzed by qualified professionals. In addition to requiring technical expertise to test for asbestos, when samples are incorrectly taken there maybe an increased health risk if fibers are released. Asbestos materials that are intact and in good condition generally do not pose a health risk. The potential for an asbestos containing material (ACM) to release harmful fibers depends primarily on its condition. Dry material that can be crumbled by hand pressure, often referred to as friable ACM, is more likely to release fibers, particularly when damaged. Materials considered nonfriable ACM, such as vinyl-asbestos floor tile, can also release harmful fibers when sanded, sawed, or otherwise disturbed. ... 

Asbestos materials may be encountered by electricians in decorative finishes such as artex ceiling finishes, plaster and floor tiles. It is also found in control gear such as flash guards and matting in fuse carriers and distribution fuse boards, and in insulation materials in vessels, containers, pipework, ceiling ducts and wall and floor partitions. 

Working with asbestos materials is not a job for anyone in the electrical industry. 

Working with asbestos materials is not a job for anyone in the electrotechnical industry. If asbestos is present in situations or buildings where you are expected to work, it should be removed by a specialist contractor before your work commences. Specialist contractors, who will wear fully protective suits and use breathing apparatus, are the only people who can safely and responsibly carry out the removal of asbestos. They will wrap the asbestos in thick plastic bags and store them temporarily in a covered and locked skip. This material is then disposed of in a special land fill site with other toxic industrial waste materials and the site monitored by the local authority for the foreseeable future. 

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