1、Designation:D364814Standard Practices for theMeasurement of Radioactivity1This standard is issued under the fixed designation D3648;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 ind
2、icates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 These practices cover a review of the accepted countingpractices currently used in radiochemical analyses.The prac-tices are divided into four sections:SectionGener
3、al Information6 11Alpha Counting12 22Beta Counting23 33Gamma Counting34 411.2 The general information sections contain informationapplicable to all types of radioactive measurements,while eachof the other sections is specific for a particular type ofradiation.1.3 The values stated in SI units are to
4、 be regarded asstandard.No other units of measurement are included in thisstandard.1.4 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 det
5、ermine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1066 Practice for Sampling SteamD1129 Terminology Relating to WaterD1943 Test Method for Alpha Particle Radioactivity ofWaterD2459 Test Method for Gamma Spectrometry of IndustrialWater and Ind
6、ustrial Waste Water(Withdrawn 1986)3D3084 Practice for Alpha-Particle Spectrometry of WaterD3085 Practice for Measurement of Low-Level Activity inWater(Withdrawn 1987)3D3370 Practices for Sampling Water from Closed ConduitsD3649 Practice for High-Resolution Gamma-Ray Spectrom-etry of WaterIEEE/ASTM
7、SI 10 American National Standard for MetricPractice2.2 ANSI/ISO Standards:4ANSI N42.14 Calibration and Use of Germanium Spectrom-eters for the Measurement of Gamma-Ray Emission Ratesof RadionuclidesISOGuidetotheExpressionofUncertaintyinMeasurement,19933.Terminology3.1 Definitions:3.1.1 For definitio
8、ns of terms used in these practices,referto Terminology D1129.For an explanation of the metricsystem,including units,symbols,and conversion factors,seeIEEE/ASTM SI 10.4.Summary of Practices4.1 The practices are a compilation of the various countingtechniques employed in the measurement of radioactiv
9、ity.Theimportant variables that affect the accuracy or precision ofcounting data are presented.Because a wide variety of instru-ments and techniques are available for radiochemicallaboratories,the types of instruments and techniques to beselected will be determined by the information desired.In asim
10、ple tracer application using a single radioactive isotopehaving favorable properties of high purity,energy,and ampleactivity,a simple detector will probably be sufficient andtechniques may offer no problems other than those related toreproducibility.The other extreme would be a laboratoryrequiringqu
11、antitativeidentificationofavarietyofradionuclides,preparation of standards,or studies of thecharacteristic radiation from radionuclides.For the latter,avariety of specialized instruments are required.Most radio-chemical laboratories require a level of information betweenthese two extremes.4.2 A basi
12、c requirement for accurate measurements is theuse of accurate standards for instrument calibration.With the1These practices are under the jurisdiction of ASTM Committee D19 on Waterand are the direct responsibility of D19.04 on Methods of Radiochemical Analysis.Current edition approved Jan.1,2014.Pu
13、blished January 2014.Originallyapproved in 1978.Last previous edition approved in 2011 as D3648 04(2011).DOI:10.1520/D3648-14.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refe
14、r to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Ba
15、rr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 present availability of good standards,only the highly diverseradiochemistry laboratories require instrumentation suitablefor producing their own radioactive standards.However,it isadvisable to compare each new standard recei
16、ved against theprevious standard.4.3 Thus,the typical laboratory may be equipped withproportional or Geiger-Mueller counters for beta counting,sodium iodide or germanium detectors,or both,in conjunctionwith multichannel analyzers for gamma spectrometry,andscintillation counters suitable for alpha-or beta-emitting radio-nuclides.5.Significance and Use5.1 This practice was developed for the purpose of summa-rizing the various generic radiometric techniques,equipment,and practices that are used for