1、Designation: D7712 11Standard Terminology forSampling and Analysis of Asbestos1This standard is issued under the fixed designation D7712; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parent
2、heses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This terminology standard is a collective vocabularyrelating to sampling and analysis of asbestos.As a convenienceto general interest, it contains most
3、 of the standard terms,definitions, and nomenclature under the jurisdiction of Com-mittee D22.1.2 Many of the entries in this terminology are copied (withattribution) from the standards of origin referenced in Section2. The standards of origin are noted in bold type at the rightmargin of the applica
4、ble definition.1.3 Certain terms in the common language that comprisemultiple concepts are included herein with the definitionspecific to standards and practices of Committee D22. Alter-native definitions for starred terms may be found in the USGSTabulation of Asbestos-Related Terminology, Open-File
5、 Re-port 02-458.2. Referenced Documents2.1 ASTM Standards:D1356 Terminology Relating to Sampling and Analysis ofAtmospheresD2946 Terminology for Asbestos and AsbestosCementProductsD5755 Test Method for Microvacuum Sampling and Indi-rect Analysis of Dust by Transmission Electron Micros-copy for Asbes
6、tos Structure Number Surface LoadingD5756 Test Method for Microvacuum Sampling and Indi-rect Analysis of Dust by Transmission Electron Micros-copy for Asbestos Mass Surface LoadingD6281 Test Method forAirborneAsbestos Concentration inAmbient and IndoorAtmospheres as Determined byTrans-mission Electr
7、on Microscopy Direct Transfer (TEM)D6480 Test Method for Wipe Sampling of Surfaces, Indi-rect Preparation, and Analysis for Asbestos StructureNumber Surface Loading by Transmission Electron Mi-croscopyD6620 Practice for Asbestos Detection Limit Based onCountsD7200 Practice for Sampling and Counting
8、Airborne Fi-bers, IncludingAsbestos Fibers, in Mines and Quarries, byPhase Contrast Microscopy and Transmission ElectronMicroscopyD7201 Practice for Sampling and Counting Airborne Fi-bers, Including Asbestos Fibers, in the Workplace, byPhase Contrast Microscopy (with an Option of Transmis-sion Elect
9、ron Microscopy)D7390 Guide for Evaluating Asbestos in Dust on Surfacesby Comparison Between Two Environments2.2 Government Standards:USGS Open-File Report 02-458 Tabulation of Asbestos-Related Terminology3. Terminologyacicular, adjthe shape shown by an extremely slendercrystal with cross-sectional d
10、imensions that are small rela-tive to its length, that is, needle-like. D6281actinolite asbestos, nasbestiform variety of the monoclinicamphibole silicate minerals of the tremolite-actinolite series.D2946activity generated aerosol, na dispersion of particles in airthat have become airborne due to ph
11、ysical disturbances suchas human activity, sweeping, airflow, etc. D7390amosite, nthe acronym assigned to grunerite asbestos, andderived from the name of the first developers of a majordeposit of this mineral. D2946amphibole, na group of more than 60 different silicateminerals with similar crystal s
12、tructures and complex com-positions that conform to the nominal formula:A021B2C5T8O22OH,F,Cl!2where:A = K, Na, Ca;B =Fe2+, Mn, Mg, Ca, Na;C = Al, Cr, Ti, Fe3+, Mg, Fe2+;andMn and T = Si, Al, Cr, Fe3+,Ti.In some varieties of amphibole, these elements can bepartially substituted by Li, Pb, Zn, Be, Ba,
13、 or Ni. Amphibolesare characterized by a complex monoclinic or orthorhombicstructure that includes a double chain of T-O tetrahedra with aT:O ratio of approximately 4:11; a variable morphology thatranges from columnar to prismatic to acicular to fibrous; andgood prismatic cleavage at angles of about
14、 56 and 124. The1This terminology standard is under the jurisdiction of ASTM Committee D22onAir Quality and is the direct responsibility of Subcommittee D22.07 on Samplingand Analysis of Asbestos.Current edition approved Sept. 1, 2011. Published October 2011. DOI:10.1520/D7712-11.1Copyright ASTM Int
15、ernational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.cleavage may not be readily exhibited by small crystals that arebound by irregular growth and fracture surfaces. D6281amphibole asbestos, nasbestiform amphibole silicate min-erals including the orthorhomb
16、ic anthophyllite series and themonoclinic cummingtonite (grunerite asbestos amosite)series, the tremolite-actinolite series, and the alkali amphi-bole (riebeckite asbestos crocidolite) series, among others.DISCUSSIONThe amphiboles contain essential (OH) groups in thestructure, and the Si:O ratio is
17、4:11. A considerable amount ofelemental substitution can take place in these varieties of asbestos. Thecrystal structures are composed of strips or ribbons of linked polyhedralthat join to form fibrils. The individual strips are made up from threecomponents; these are two double chains of linked (Si
18、, Al)O4 tetrahe-dra and a strip of linked MgO6, FeO6,or AlO6octahedra. D2946,namphibole in an asbestiform habit. D6281D6480analytical sensitivity, nthe calculated airborne asbestosstructure concentration in asbestos structures/L, equivalentto the counting of one asbestos structure in the analysis.D6
19、281,nthe calculated airborne asbestos structure concentrationin asbestos structures/square centimeter, equivalent to count-ing of one asbestos structure in the analysis calculated usingEq. 2 in D6480. D6480anthophyllite asbestos, nasbestiform variety of the ortho-rhombic amphibole silicate minerals
20、of the anthophylliteseries.DISCUSSIONIts empirical formula is Mg7Si8O22(OH)2. Its ChemicalAbstracts number is 77536-67-5. D2946area sample, nan air sample collected so as to represent theconcentration of airborne dust in a specific mine location, orarea, or room of a workplace. D7200,nan air sample
21、collected so as to represent the concen-tration of airborne dust in a specific area or room, which, inthe case of this practice, refers to an area or room of aworkplace. D7201asbestiform, adjhaving an inherent fine-textured morphol-ogy, resulting from unequal relative development of theprincipal cry
22、stal axes in a silicate mineral, that predeter-mines subdivision into strong flexible fibers having micro-scopic to submicroscopic thickness and a high length towidth ratio when the mineral is subjected to comminution.DISCUSSIONTerm derived from “asbestos.” D2946, adja special type of fibrous habit
23、in which the fibers areseparable into thinner fibers and ultimately into fibrils. Thishabit accounts for greater flexibility and higher tensilestrength than other habits of the same mineral. D5755D5756, adja specific type of fibrous habit in which the fibers areseparable into thinner fibers and ulti
24、mately into fibrils. Thishabit accounts for greater flexibility and higher tensilestrength than other habits of the same mineral. D6281, adja specific type of fibrous mineral growth habit inwhich the fibers and fibrils exhibit a polyfilamentous growthhabit and possess high tensile strength and flexi
25、bility. Allmaterials regulated as asbestos are asbestiform, but not allasbestiform minerals are classified as asbestos. Characteris-tics such as tensile strength and flexibility cannot be ascer-tained from microscopic evaluation. D7200D7201asbestos, nthe generic term for naturally occurring inorgani
26、chydrated silicates, occurring in layered structures composedof chains of silicon and oxygen tetrahedra, that can subdi-vide into flexible fibers. D2946,na collective term that describes a group of naturallyoccurring, inorganic, highly fibrous, silicate dominated min-erals, which are easily separate
27、d into long, thin, flexiblefibers when crushed or processed.DISCUSSIONIncluded in the definition are the asbestiform varietiesof: serpentine (chrysotile); riebeckite (crocidolite); grunerite (gruneriteasbestos); anthophyllite (anthophyllite asbestos); tremolite (tremoliteasbestos); and actinolite (a
28、ctinolite asbestos). The amphibole mineralcompositions are defined in accordance with the nomenclature of theInternational Mineralogical Association. D5755,na collective term that describes a group of naturallyoccurring, inorganic, highly fibrous, silicate minerals, whichare easily separated into lo
29、ng, thin, flexible fibers whencrushed or processed.DISCUSSIONIncluded in the definition are the asbestiform varietiesof: serpentine (chrysotile); riebeckite (crocidolite); grunerite (amosite);anthophyllite (anthophyllite asbestos); tremolite (tremolite asbestos);and actinolite (actinolite asbestos).
30、 The amphibole mineral composi-tions are defined according to nomenclature of the InternationalMineralogical Association. D5756,na collective term that describes a group of naturallyoccurring, inorganic, highly-fibrous, silicate minerals, thatare easily separated into long, thin, flexible, strong fi
31、berswhen crushed or processed.DISCUSSIONIncluded in the definition are the asbestiform varietiesof serpentine (chrysotile); riebeckite (crocidolite); grunerite (gruneriteasbestos Amosite); anthophyllite (anthophyllite asbestos); tremolite(tremolite asbestos); and actinolite (actinolite asbestos). Th
32、e amphibolemineral compositions are defined according to the nomenclature of theInternational Mineralogical Association. D6281D6480,na term applied to six specific silicate minerals belong-ing to the serpentine and amphibole groups, which havecrystallized in the asbestiform habit, causing them to be
33、easily separated into long, thin, flexible, strong fibers whencrushed or processed. The Chemical Abstracts Service Reg-istry Numbers of the most common asbestos varieties are:chrysotile (12001-29-5), riebeckite asbestos (crocidolite)(12001-28-4), grunerite asbestos (Amosite) (12172-73-5),anthophylli
34、te asbestos (77536-67-5), tremolite asbestos(77536-68-6) and actinolite asbestos (77536-66-4). Theprecise chemical composition of each species varies with thelocation from which it was mined. Other amphibole mineralswhich exhibit the characteristics of asbestos have also beenobserved. The nominal co
35、mpositions of the most commonasbestos varieties are: Chrysotile Mg3Si2O5(OH)4, Crocido-lite Na2Fe32+Fe23+Si8O22(OH)2, Amosite(Mg,Fe)7Si8O22(OH)2, Anthophyllite(Mg,Fe)7Si8O22(OH)2, TremoliteD7712 112Ca2(Mg,Fe)5Si8O22(OH)2Mg/(Mg+Fe2+) 0.9-1.0, Actino-lite Ca2(Mg,Fe)5Si8O22(OH)2Mg/(Mg+Fe2+) 0.5-0.9.NOT
36、E 1Actinolite compositions in which Mg/(Mg+Fe2+) is between0 and 0.5 are referred to as ferroactinolite.asbestos fiber, nacicular silicate mineral, with a structurebased upon silicon-oxygen tetrahedra, that fits the definitionof a fiber, and is composed of single crystals in predomi-nately parallel
37、orientation.DISCUSSIONCommon usage also designates a collectivity of asbes-tos fibers as asbestos fiber. D2946,na fiber of asbestos that meets the criteria specifiedbelow for “fiber.” Phase Contrast Microscopy (PCM) doesnot identify fibers unequivocally as asbestos. Under the lightmicroscope, a popu
38、lation of asbestos fibers may appear as amixture of fiber agglomerates, fiber bundles (polyfilamen-tous growth, unique to asbestiform fibers), fibers with splitends, and single fibers, the relative occurrence and frequencyof each type depending on the situation. D7200D7201asbestos structure, na term
39、 applied to isolated fibers or toany connected or overlapping grouping of asbestos fibers orbundles, with or without other nonasbestos particles.D6281,na term applied to isolated fibers or to any connected oroverlapping grouping of asbestos fibers or bundles, with orwithout other nonasbestos particl
40、es. D6480aspect ratio, nthe ratio of the length of a fibrous particle toits average width. D5755D5756,nthe ratio of length to width of a particle. D6281D6480,nthe ratio of the length of a fiber to its width. D7200D7201background, na statistical distribution of structures intro-duced by (i) analyst c
41、ounting errors and (ii) contaminationon an unused filter or contamination as a consequence of thesample collection and sample preparation steps.DISCUSSIONThis definition of background is specific to this prac-tice. The only counting errors considered in this definition of back-ground are errors that
42、 result in an over-count (that is, false positives).Analyst counting errors are errors such as, determining the length ofstructures or fibers and whether, based on length, they should becounted; counting artifacts as fibers; determining the number ofstructures protruding from a matrix; and interpret
43、ing a cluster as one,two, or more structures that should be counted only as zero or onestructure. For purposes of developing the DL, assume that backgroundcontamination sources have been reduced to their lowest achievablelevels. D6620background samples, nsamples taken from surfaces that areconsidere
44、d to have concentrations of asbestos in surface dustthat are representative of conditions that exist in an environ-ment that is affected by only prevailing conditions and hasnot experienced events, disturbances or activities unusual forthe environment. D7390blank, na structure count made on TEM spec
45、imens preparedfrom an unused filter to determine the background measure-ment. D6281,na filter that has not been used to collect asbestos fromthe target environment. D6620DISCUSSIONBlanks are used in this practice to determine the degreeof asbestos contamination that is reflected in asbestos measurem
46、ents.Contamination may be on the virgin filter or introduced in handling thefilter in the field or when preparing it for inspection with a microscope.The data required to determine the degree of contamination consists,therefore, of measurements of field blanks that have experienced thefull preparati
47、on process.bundle, nan assemblage of asbestos in which the fibersremain entirely in their original close packed parallel con-figuration (or not appreciably displaced therefrom) andhaving a transverse dimension typically between 2 and 8mm. D2946,na structure composed of three or more fibers in aparal
48、lel arrangement with the fibers closer than one fiberdiameter to each other. D5755D5756D6480camera length, nthe equivalent projection length betweenthe specimen and its electron 195 diffraction pattern, in theabsence of lens action. D6281D6480chrysotile, nan asbestos mineral belonging to the serpent
49、inegroup, having a chemical composition close toMg3SiO5(OH)4.DISCUSSIONModerate amounts of aluminum may substitute forsilicon and moderate amounts of iron may substitute for magnesium.Small amounts of MnO, CaO, K2O, and Na2O are also reported in thechemical analysis. The crystal structure of chrysotile asbestos consistsof double layers, each consisting of a layer of linked SiO4tetrahedrathat is coordinated to a second layer of linked MgO2(OH)4octahedralinked through the sharing of oxygen atoms; the composite double layerrolls u
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