1、Designation:D605996(Reapproved 2011)Standard Test Method forDetermining Concentration of Airborne Single-CrystalCeramic Whiskers in the Workplace Environment byScanning Electron Microscopy1This standard is issued under the fixed designation D6059;the number immediately following the designation indi
2、cates the year 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 method covers the sampling methods anda
3、nalysis techniques used to assess the airborne concentrationand size distribution of single-crystal ceramic whiskers(SCCW),such as silicon carbide and silicon nitride,which mayoccur in and around the workplace where these materials aremanufactured,processed,transported,or used.This testmethod is bas
4、ed on the collection of fibers by filtration of aknown quantity of air through a filter.The filter is subsequentlyevaluated with a scanning electron microscope(SEM)for thenumber of fibers meeting appropriately selected morphologicaland compositional criteria.This test method has the ability todistin
5、guish among many different types of fibers based onenergy dispersive X-ray spectroscopy(EDS)analysis.This testmethod may be appropriate for other man-made mineral fibers(MMMF).1.2 This test method is applicable to the quantitation offibers on a collection filter that are greater than 5 m in length,l
6、ess than 3 m in width,and have an aspect ratio equal to orgreater than 5:1.The data are directly convertible to astatement of concentration per unit volume of air sampled.Thistest method is limited by the diameter of the fibers visible bySEM(typically greater than 0.10 to 0.25 m in width asdetermine
7、d in 12.1.5)and the amount of coincident interfer-ence particles.1.3 A more definitive analysis may be necessary to confirmthe presence of fibers with diameters 0.10 to 0.25 m inwidth.For this purpose,a transmission electron microscope(TEM)is appropriate.The use of the TEM method for theidentificati
8、on and size measurement of SCCW is described inPractice D6058 and Test Method D6056.1.4 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.5 This standard does not purport to address all of thesafety concerns,if any,associated wi
9、th 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.Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD1356 Terminology Relating to S
10、ampling and Analysis ofAtmospheresD4532 Test Method for Respirable Dust in Workplace At-mospheres Using Cyclone SamplersD6056 Test Method for Determining Concentration of Air-borne Single-Crystal Ceramic Whiskers in the WorkplaceEnvironment by Transmission Electron MicroscopyD6057 Test Method for De
11、termining Concentration of Air-borne Single-Crystal Ceramic Whiskers in the WorkplaceEnvironment by Phase Contrast MicroscopyD6058 Practice for Determining Concentration of AirborneSingle-Crystal Ceramic Whiskers in the Workplace Envi-ronmentE691 Practice for Conducting an Interlaboratory Study toDe
12、termine the Precision of a Test MethodE766 Practice for Calibrating the Magnification of a Scan-ning Electron Microscope3.Terminology3.1 Definitions:3.1.1 analytical sensitivity,nairborne fiber concentrationrepresented by a single fiber counted in the SEM.3.1.1.1 DiscussionAlthough the terms fiber a
13、nd whiskerare,for convenience,used interchangeably in this test method,whisker is correctly applied only to single-crystal fiberswhereas a“fiber”may be single-or poly-crystalline or may benoncrystalline.1This test method is under the jurisdiction of ASTM Committee D22 on AirQuality and is the direct
14、 responsibility of Subcommittee D22.04 on Workplace AirQuality.Current edition approved Oct.1,2011.Published October 2011.Originallyapproved in 1996.Last previous edition approved in 2006 as D6059 96(2006).DOI:10.1520/D6059-96R11.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orc
15、ontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.1.2 aspect ratio,nthe ra
16、tio of the length of a fiber to itswidth.3.1.3 fiber,nfor the purpose of this test method,anelongated particle having a length greater than 5 m,a widthless than 3 m,and an aspect ratio equal to or greater than 5:1.3.1.4 fibrous,adjcomposed of parallel,radiating,or inter-laced aggregates of fibers,from which the fibers are sometimesseparable.That is,the aggregate may be referred to as fibrouseven if it is not composed of separable fibers,but has thatdistinct appearance.The term fibrous is used in
