ASTM_D_7784_-_20.pdf

Designation:D778420Standard Practice for theRapid Assessment of Gamma-ray Emitting Radionuclides inEnvironmental Media by Gamma Spectrometry1This standard is issued under the fixed designation D7784;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.1.Scope1.1 This practice covers the quantification of radionuclidesin environmental media(for example,water,soil,vegetation,food)by means of simple preparation and counting with ahigh-resolution gamma ray detector.Because the practice isdesigned for rapid analysis,extensive efforts to ensure homo-geneity or ideal sample counting conditions are not taken.1.2 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.1.3 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.1.4 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:2C998 Practice for Sampling Surface Soil for RadionuclidesD1129 Terminology Relating to WaterD3370 Practices for Sampling Water from Flowing ProcessStreamsD3649 Practice for High-Resolution Gamma-Ray Spectrom-etry of WaterD7282 Practice for Set-up,Calibration,and Quality Controlof Instruments Used for Radioactivity MeasurementsD7902 Terminology for Radiochemical Analyses2.2 Other Documents:BIPM-5 Decay Data Evaluation Project(DDEP)3NUDAT243.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this standard,refer toTerminologies D1129 and D7902.4.Summary of Practice4.1 Following sample collection,sample material is placedin a suitable container for analysis by a gamma spectrometrysystem.A suitable container is defined as a container whichwill both hold the sample in a fixed geometry and for which thegamma spectrometry system has been calibrated.For solidsamples,the samples may be ground,sieved,or otherwiseprepared for the purpose of volume reduction,homogenization,or conformance to the calibration standard,as desired.5.Significance and Use5.1 This practice was developed for the rapid determinationof gamma-emitting radionuclides in environmental media.Theresults of the test may be used to determine if the activity ofthese radionuclides in the sample exceeds the action level forthe relevant incident or emergency response.The detectionlimitswillbedependentonsamplesize,countingconfiguration,and the detector system in use.5.2 In most cases,a sample container which is large indiameter and short in height relative to the detector willprovide the best gamma-ray detection efficiency.For samplesof water or other low-Z materials(for example,vegetation),there-entrant or Marinelli-style beaker may yield the best gamma-ray detection efficiency.5.3 The density of the sample material and physical param-eters of the sample container(for example,diameter,height,material)may have significant consequences for the accuracyof the sample analysis as compared to the calibration.For this1This practice is under the jurisdiction of ASTM Committee D19 on Water andis the direct responsibility of Subcommittee D19.04 on Methods of RadiochemicalAnalysis.Current edition approved Dec.15,2020.Published January 2021.Originallyapproved in 2012.Last previous edition approved in 2012 as D7784 12.DOI:10.1520/D7784-20.2For 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 BIPM,Svres Cedex,France,https:/www.bipm.org.4Available from National Nuclear Data Center at Brookhaven NationalLaboratory,W Princeton Ave,Yaphank,NY 11980,http:/www.nndc.bnl.gov.Copyright 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.1reason,the ideal calibration material and container(oftenreferred to as geometry)will be exactly the same as thesamples to be analyzed.Di