ASTM_D_4525_-_13e2.pdf

Designation:D4525132Standard Test Method forPermeability of Rocks by Flowing Air1This standard is issued under the fixed designation D4525;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 parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1NOTEEditorial corrections were made throughout in February 2014.2NOTEEditorially updated units of measurement statement in April 2018.1.Scope*1.1 This test method covers the determination of the coef-ficient of specific permeability for the flow of air throughrocks.The method establishes representative values of thecoefficient of permeability of rocks or well-indurated soils.1.2 This test method is limited to permeability valuesgreater than 9.869 10-18m2(0.01 millidarcy),and is limitedto rocks free of oil or unctuous matter.1.3 The values stated in SI units are to be regarded asstandard.The values given in parentheses after SI units areprovided for information only and are not considered standard.Reporting of test results in units other than SI shall not beregarded as nonconformance with this test method.1.4 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D6026.1.4.1 The procedures used to specify how data are collected/recorded or calculated,in this standard are regarded as theindustry standard.In addition,they are representative of thesignificant digits that generally should be retained.The proce-dures used do not consider material variation,purpose forobtaining the data,special purpose studies,or any consider-ations for the users objectives;and it is common practice toincrease or reduce significant digits of reported data to becommensurate with these considerations.It is beyond the scopeof this standard to consider significant digits used in analyticalmethods for engineering design.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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D653 Terminology Relating to Soil,Rock,and ContainedFluidsD3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD6026 Practice for Using Significant Digits in GeotechnicalData2.2American Petroleum Institute Standard:3RP-40 Recommended Practice for Core Analysis Procedure3.Terminology3.1 DefinitionsFor definitions of common technical termsin this standard,refer to Terminology D653.4.Summary of Test Method4.1 The permeability of a rock sample is measured byflowing dry air through the specimen and measuring theabsolute pressure,the flow rate,and absolute pressure differ-ential of the air.Three or more tests are performed on a sampleat different mean air pressure values.The permeability valuesare plotted as a function of the reciprocal mean absolutepressure;those points lying on a straight line are extrapolatedto a value corresponding to an infinite mean air pressure toobtain an equivalent permeability value for liquids.5.Significance and Use5.1 This test method is designed to measure the permeabil-ity to air of a small sample of rock.By extrapolation,this test1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.12 on Rock Mechanics.Current edition approved Nov.1,2013.Published December 2013.Originallyapproved in 1985.Last previous edition approved in 2008 as D4525 08.DOI:10.1520/D4525-13E02.2For 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 Summary page onthe ASTM website.3Available from American Petroleum Institute(API),1220 L.St.,NW,Washington,DC 20005-4070,http:/www.api.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 metho