1、Designation:D2752/D2752M88(Reapproved 2011)1Standard Test Methods forAir Permeability of Asbestos Fibers1This standard is issued under the fixed designation D2752/D2752M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of las
2、t revision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1NOTEUnits information was editorially corrected in February 2012.1.Scope1.1 These test methods cover the measurement of therelative degr
3、ee of openness or degree of fiberization of milledasbestos fiber by air permeability instruments.1.2 Method A is the recommended procedure and describesa determination by means of the Rapid SurfaceArea apparatus.This test method is limited to fibers with an effective surfacearea in the range from 10
4、 to 250 dm2/g 490 to 12 000 ft2/lb.1.3 Method B is an alternative procedure and covers the useof the Dyckerhoff apparatus.This test method is limited tofibers within the range from 10 to 600 Dyckerhoff seconds.1.4 Only those asbestos specimens which are of similarspecific gravities will bear strict
5、comparison by these airpermeability methods since differences in density result inspecimens being tested under different conditions of porosity.1.5 Samples containing excessive quantities of nonfibrousparticles or contaminants will not give reliable or meaningfulresults.1.6 The values stated in eith
6、er SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.1.7 WarningBreathing
7、 of asbestos dust is hazardous.Asbestos and asbestos products present demonstrated healthrisks for users and for those with whom they come into contact.In addition to other precautions,when working with asbestos-cement products,minimize the dust that results.For informa-tion on the safe use of chrys
8、otile asbestos,refer to“Safe Use ofChrysotile:A Manual on Preventive and Control Measures.”21.8 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 practice
9、s and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:3D2590 Test Method for Sampling Chrysotile AsbestosD3879 Test Method for Sampling Amphibole Asbestos(Withdrawn 2009)4E11 Specification for Woven Wire Test Sieve Cloth and TestSievesE177
10、 Practice for Use of the Terms Precision and Bias inASTM Test Methods2.2 Other Standard:5NNN-P-1475B Federal Specification for Paper,Filter,Ana-lytical3.Summary of Test Methods3.1 In both test methods the resistance to air flow of acompressed specimen of fixed weight and volume is deter-mined.3.2 Te
11、st Method A:3.2.1 The apparatus is arranged so that the total resistance toair flow remains equal to a fixed hydraulic pressure head.Totalresistance includes the resistance of the specimen and thepressure drop across a calibrated capillary tube of knownresistance.The contribution of the specimen to
12、total resistanceis measured on a manometer calibrated in specific surface areaunits.3.2.2 Optional calibration of the manometer in equivalentDyckerhoff seconds,which are the units of Test Method B,permits comparison of results by both test methods on the samebasis.1These test methods are under the j
13、urisdiction of ASTM Committee C17 onFiber-Reinforced Cement Products and are the direct responsibility of Subcommit-tee C17.03 on Asbestos-Cement Sheet Products and Accessories.Current edition approved Nov.1,2011.Published February 2012.Originallyapproved in 1968.Last previous edition approved in 20
14、06 as D2752 88(2006).DOI:10.1520/D2752_D2752M-88R11E01.2Available from The Asbestos Institute,http:/ referenced 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 Su
15、mmary page onthe ASTM website.4The last approved version of this historical standard is referenced onwww.astm.org.5Available from the Superintendent of Documents,U.S.Government PrintingOffice,Washington,DC 20402.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 1942
16、8-2959.United States1 3.3 Test Method B:3.3.1 The time required to draw a given volume of airthrough the specimen under specified conditions of varyinghydraulic head is determined.This time is taken as a measureof the air permeability of the specimen.4.Significance and Use4.1 The degree of fiberization or subdivision of the asbestosfiber bundles in a specimen is related to its resistance to airflow.The number and size of the pores in the specimen are afunction of the size of the fiber bundles an
