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Glossary of Asbestos-related Terms and Acronyms

These terms generally come from the Framework for Investigating Asbestos-Contaminated Superfund Sites (PDF) (71 pp, 849K) OSWER Directive 9200.0-68, September 2008.

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AAHAU: Airborne Asbestos Health Assessment Update (1986)

ABS: Activity-based sampling
An empiric approach in which airborne concentrations of asbestos are measured during an event where the source material (soil or dust) is disturbed rather than predicted or modeled from source material concentration.

ACBM: Asbestos-containing building materials

ACM: Asbestos containing material

Actinolite: A mineral in the amphibole group. It is generally not used commercially, but is a common impurity in chrysotile asbestos.

AHERA: Asbestos Hazard Emergency Response Act of 1986
In 1986, the Asbestos Hazard Emergency Response Act (AHERA) was signed into law as Title II of the Toxic Substance Control Act. Additionally, the Asbestos School Hazard Abatement Reauthorization Act (ASHARA), passed in 1990, requires accreditation of personnel working on asbestos activities in schools, and public and commercial buildings. See applicability discussion (Section 2).

Amosite: A type of asbestos in the amphibole group; it is also known as brown asbestos.

Amphibole: A group of double chain silicate minerals.

Analytical sensitivity: The sample-specific lowest concentration of asbestos the laboratory can detect for a given method.

Anthophyllite: A type of asbestos in the amphibole group; it is also known as azbolen asbestos.

Asbestiform: Fibrous minerals possessing the properties of commercial grade asbestos (e.g., flexibility, high tensile strength, or long, thin fibers occurring in bundles).

Asbestos: The generic name used for a group of naturally occurring mineral silicate fibers of the serpentine and amphibole series, displaying similar physical characteristics although differing in composition.

Asbestosis: A non-cancerous disease associated with inhalation of asbestos fibers and characterized by scarring of the air-exchange regions of the lungs.

Aspect ratio: Length to width ratio of a particle or fiber.

ASTM: American Society for Testing and Materials

ATSDR (Agency for Toxic Substances and Disease Registry): A principal federal public health agency involved with hazardous waste issues, responsible for preventing or reducing the harmful effects of exposure to hazardous substances on human health and quality of life. ATSDR is part of Center for Disease Control and Prevention which is part of the U.S. Department of Health and Human Services.

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Bulk sample: A sample of suspected media (e.g., soil or dust) is obtained from a site to be analyzed microscopically for asbestos content. Bulk sample analysis can be part of a process to assess the hazard from asbestos at a site.

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CARB 435 (California Air Resources Board analytical method 435): A specialized polarized light microscopy (PLM) method used for testing asbestos content in the serpentine aggregate storage piles, on conveyer belts, and on covered surfaces such as roads, play-yards, shoulders and parking lots. The method includes reporting the asbestos content by performing a 400 point count technique which has a detection limit of 0.25%. Many agencies and laboratories also use this method for measuring asbestos in soil. The method is undergoing revision (completion anticipated in 2009).

Carcinogen: Any substance that causes cancer.

CERCLA: Comprehensive Environmental Response, Compensation, and Liability Act

Chrysotile: A fibrous member of the serpentine group of minerals. It is the most common form of asbestos used commercially, also referred to as white asbestos.

Cleavage Fragment: Fragments that may be formed by crushing, mining, or breaking massive materials.

Contaminant: A substance that is either present in an environment where it does not belong or is present at levels that might cause harmful (adverse) health effects.

Continuous Exposure: Exposure that occurs 24 hours/day, 365 days/year.

Crocidolite: A type of asbestos in the amphibole group; it is also known as blue asbestos.

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Detection limit: The minimum concentration of an analyte in a sample, that with a high level of confidence is not zero.

Direct preparation: In direct preparation, the filter is examined by microscopy. In contrast with indirect preparation, where a filter with too much material undergoes a separation step (commonly dispersion in water) to allow for analysis.

Dose: The amount of a substance to which a person is exposed (air, soil, dust, or water) over some time period.

DQO: Data Quality Objectives.

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ED (Electron diffraction): A specialized technique used to study matter by firing electrons at a sample and observing the resulting interference pattern. See Appendix C.

EDX: Energy Dispersive X-Ray Analysis

ELCRs: Excess lifetime cancer risks

EPA: United States Environmental Protection Agency

EPC: Exposure point concentration

Exposure: Contact with a substance by swallowing, breathing, or touching the skin or eyes. Exposure may be short-term [acute exposure], of intermediate duration, or long-term [chronic exposure].

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f/cc (Fibers per cubic centimeter): Units of measurement for asbestos in air.

Fibrous habit: Having the morphologic properties similar to organic fibers.

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GOs (Grid openings): An area that overlays a mounted sample to aid in its microscopic examination.

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HASP: Health and safety plan

Hazardous substance: Any material that poses a threat to public health and/or the environment. Typical hazardous substances are materials that are toxic, corrosive, ignitable, explosive, or chemically reactive.

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ICs (Institutional controls): Institutional controls are actions, such as legal controls, that help minimize the potential for human exposure to contamination by ensuring appropriate land or resource use.

Indirect preparation: A method whereby a filter with too much material undergoes a separation step to allow for analysis.

Ingestion: The act of swallowing something through eating, drinking, or mouthing objects. A hazardous substance can enter the body this way [see route of exposure].

Inhalation: The act of breathing. A hazardous substance can enter the body this way [see route of exposure].

IRIS (Integrated Risk Information System: A compilation of electronic reports on specific substances found in the environment and their potential to cause human health effects.

ISO 10312 (International Organization for Standardization Method 10312): See Appendix C for details.

IUR (Inhalation unit risk): The excess lifetime cancer risk estimated to result from continuous exposure to an agent at a concentration 1 µg/m³ in air.

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MCE (Mixed cellulose ester): A type of filter used for air sampling.

Media: Soil, water, air, plants, animals, or any other part of the environment that can contain contaminants.

Mesothelioma: A malignant tumor of the covering of the lung or the lining of the pleural and abdominal cavity often associated with exposure to asbestos.

Microvacuum samples: A microvacuum sample, commonly called microvacuum, as per ASTM D5755, is similar to a wipe sample with the exception that a predefined area is “vacuumed” using a high-volume air pump equipped with a sample cassette that contains a cellulose filter instead of wiping with a wet wipe.

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NCP: National Contingency Plan

NESHAP (National Emission Standards for Hazardous Air Pollutants): Section 112 of the Clean Air Act requires EPA to develop emission standards for hazardous air pollutants. In response, EPA published a list of hazardous air pollutants and promulgated the National Emission Standards for Hazardous Air Pollutants (NESHAP) regulations.

NIOSH (National Institute for Occupational Safety and Health): The National Institute for Occupational Safety and Health (NIOSH) is the federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness. NIOSH is part of the Centers for Disease Control and Prevention in the Department of Health and Human Services.

NIOSH 7400: A light microscopy analytical method, also known as NIOSH Phase Contrast Microscopy [PCM] Method 7400.

NIOSH 9002: A polarized light microscopy (PLM) analytical method useful for the qualitative identification of asbestos and the semi-quantitative determination of asbestos content of bulk samples. The method measures percent asbestos as perceived by the analyst in comparison to standard area projections, photos, and drawings, or trained experience. The method is not applicable to samples containing large amounts of fine fibers below the resolution of the light microscope.

NOA: Naturally occurring asbestos.

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OSHA (Occupational Safety and Health Administration): The Occupational Safety and Health Administration, since its inception in 1971, aims to ensure employee safety and health in the United States by working with employers and employees to create better working environments.

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PC (Polycarbonate): A type of filter used for asbestos air sampling.

PCM (Phase contrast microscopy): A light-enhancing microscope technology that employs an optical mechanism to translate small variations in phase into corresponding changes in amplitude, resulting in high-contrast images. Historically, this method was used to measure airborne fibers in occupational environments; however, it cannot differentiate asbestos fibers from other fibers.

PCMe (PCM-equivalent): This refers to chrysotile and amphibole structures identified through transmission electron microscopy (TEM) analysis that are equivalent to those that would be identified in the same sample through phase contrast microscopy analysis, with the main difference being that TEM additionally permits the specific identification of asbestos fibers. PCMe structures are asbestiform structures greater than 5 microns in length having at least a 3 to 1 length to width (aspect) ratio.

Personal air monitor: Also known as a low-flow or low-volume sample pump, this is an air sample pump that is portable so that it can be worn by a member of the sampling team during activity based sample collection. The air flow for a personal sample pump is typically 1 to 10 liters per minute.

Pleural fibrosis: The development of fibrous tissue in the pleura.

PLM (Polarized light microscopy): A microscope technology that uses the polarity (or orientation) of light waves to provide better images than a standard optical microscope.

PPE: Personal protective equipment

Prismatic: A term commonly used in descriptions of minerals for crystals having the shape of a prism.

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QAPP (Quality Assurance Project Plan): The EPA has developed the QAPP as a tool for project managers and planners to document the type and quality of data needed for environmental decisions and to describe the methods for collecting and assessing those data. The development, review, approval, and implementation of the QAPP are components of EPA’s mandatory Quality System.

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RfC (Reference concentration): An estimate (with uncertainty spanning perhaps an order of magnitude) of a continuous inhalation exposure to the human population (including sensitive subgroups) that is likely to be without an appreciable risk of deleterious non-cancer health effects during a lifetime. The inhalation reference concentration is for continuous inhalation exposures.

RME: Reasonable maximum exposure

Route of exposure: The way people come into contact with a hazardous substance. Three routes of exposure are breathing [inhalation], eating or drinking [ingestion], or contact with the skin [dermal contact].

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s/cc (Structures per cubic centimeter): Units of measurement for asbestos in air.

SAED (Selected area electron diffraction): A crystallographic laboratory technique, a specialized electron microscopy technique, which can be performed inside a transmission electron microscope (TEM).

SAP (Sampling and Analysis Plan): A plan intended assist organization in documenting the procedural and analytical requirements for a one-time or time-limited project involving the collection of water, soil, sediment, or biological samples taken to characterize areas of potential environmental contamination. It combines, in a short form, the basic elements of a Quality Assurance Project Plan (QAPP) and a Field Sampling Plan (FSP).

Serpentine: A name given to several members of a polymorphic group of magnesium silicate minerals—those having essentially the same chemistry but different structures or forms. Chrysotile asbestos is a member of the serpentine group.

SOP: Standard operating procedure.

Stationary air monitor: An air sample monitor that is placed in a single location and is not moved during one or more sampling events.

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TEM (Transmission electron microscopy): A microscope technology and an analytical method to identify and count the number of asbestos fibers present in a sample. It uses the properties of electrons to provide more detailed images than polarized light microscopy (PLM).  Capable of achieving a magnification of 20,000x.

Tremolite: A mineral in the amphibole group, that occurs as a series in which magnesium and iron can freely substitute for each other. Tremolite is the mineral when magnesium is predominant; otherwise, the mineral is actinolite. It is generally not used commercially in the United States.

TSCA (Toxic Substances Control Act): The Toxic Substances Control Act (TSCA) of 1976 was enacted by Congress to give EPA the ability to track the 75,000 industrial chemicals currently produced or imported into the United States.

TWF (Time Weighting Factor): This factor accounts for less-than-continuous exposure during a year.

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UCL: Upper confidence limit.

UR: Unit Risk.

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Vermiculite: A chemically inert, lightweight, fire resistant, and odorless magnesium silicate material that is generally used for its thermal and sound insulation in construction and for its absorbent properties in horticultural applications. A major source of vermiculite is the mine in Libby, Montana, which has been demonstrated to contain various amounts of amphibole minerals.

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Wipe sample: A wipe sample consists of using a wipe and a wetting agent that is wiped over a specified area using a template.  The wipe picks up settled dust in the template area and provides an estimate of the number of fibers per area.

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