1、Designation:D628115Standard Test Method forAirborne Asbestos Concentration in Ambient and IndoorAtmospheres as Determined by Transmission ElectronMicroscopy Direct Transfer(TEM)1This standard is issued under the fixed designation D6281;the number immediately following the designation indicates the y
2、ear oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method2is an analytical procedure usingtransmissio
3、n electron microscopy(TEM)for the determinationof the concentration of asbestos structures in ambient atmo-spheres and includes measurement of the dimension of struc-tures and of the asbestos fibers found in the structures fromwhich aspect ratios are calculated.1.1.1 This test method allows determin
4、ation of the type(s)of asbestos fibers present.1.1.2 This test method cannot always discriminate betweenindividual fibers of the asbestos and non-asbestos analogues ofthe same amphibole mineral.1.2 This test method is suitable for determination of asbes-tos in both ambient(outdoor)and building atmos
5、pheres.1.2.1 This test method is defined for polycarbonatecapillary-pore filters or cellulose ester(either mixed esters ofcellulose or cellulose nitrate)filters through which a knownvolume of air has been drawn and for blank filters.1.3 The upper range of concentrations that can be deter-mined by th
6、is test method is 7000 s/mm2.The air concentrationrepresented by this value is a function of the volume of airsampled.1.3.1 There is no lower limit to the dimensions of asbestosfibers that can be detected.In practice,microscopists vary intheir ability to detect very small asbestos fibers.Therefore,a
7、minimum length of 0.5 m has been defined as the shortestfiber to be incorporated in the reported results.1.4 The direct analytical method cannot be used if thegeneral particulate matter loading of the sample collection filteras analyzed exceeds approximately 10%coverage of thecollection filter by pa
8、rticulate matter.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2
9、.Referenced Documents2.1 ASTM Standards:3D1193 Specification for Reagent WaterD1356 Terminology Relating to Sampling and Analysis ofAtmospheresD1357 Practice for Planning the Sampling of the AmbientAtmosphereD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Bl
10、ack ManufacturingIndustriesD6620 Practice for Asbestos Detection Limit Based onCountsE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 ISO Standard:4ISO 10312 Ambient air-Determ
11、ination of asbestos fibres-Direct-transfer transmission electron microscopy method3.Terminology3.1 For definitions of general terms used in this test method,refer to Terminology D1356(see 2.1).3.2 Definitions of Terms Specific to This Standard:3.2.1 acicularthe shape shown by an extremely slendercry
12、stal with cross-sectional dimensions that are small relativeto its length,that is,needle-like.1This test method is under the jurisdiction of ASTM Committee D22 on AirQuality and is the direct responsibility of Subcommittee D22.07 on Sampling andAnalysis of Asbestos.Current edition approved Dec.1,201
13、5.Published January 2016.Originallyapproved in 1998.Last previous edition approved in 2009 as D6281 09.DOI:10.1520/D6281-16.2This test method was adapted from International Standard ISO 10312“AirqualityDetermination of asbestos fibresDirect transfer transmission electronmicroscopy method.”3For refer
14、enced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.4Available from American National Standards Institute(ANSI),25 W.43rd St.,4t
15、h Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.2 amphibolea group of more than 60 different silicateminerals with similar crystal structures and complex composi-tions that conform to the n
16、ominal formula:A021B2C5T8O22OH,F,Cl!2(1)where:A=K,Na,Ca,B=Fe2+,Mn,Mg,Ca,Na,C=Al,Cr,Ti,Fe3+,Mg,Fe2+,Mn,andT=Si,Al,Cr,Fe3+,Ti.In some varieties of amphibole,these elements can bepartially substituted by Li,Pb,Zn,Be,Ba,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 ang
