1、Designation: D7282 06D7282 14Standard Practice forSet-up, Calibration, and Quality Control of Instruments Usedfor Radioactivity Measurements1This standard is issued under the fixed designation D7282; the number immediately following the designation indicates the year oforiginal adoption or, in the c
2、ase 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 consensus criteria for the calibration and quality control of nuclea
3、r instruments. This practice isprovided for establishing appropriate quality control parameters at instrument startup, calibration of nuclear counting instrumentsand the continuing monitoring of quality control parameters. Calibrations are usually performed to establish the operatingparameters of th
4、e instrument. This practice addresses the typically used nuclear counting instruments: alpha spectrometer, gammaspectrometer, gas proportional counter and liquid scintillation counter.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this
5、 The valuesgiven in parentheses are mathematical conversions that are provided for information only and are not considered standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to estab
6、lish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1129 Terminology Relating to WaterD3648 Practices for the Measurement of RadioactivityD4375 Practice for Basic Statistics in Committee D19 on
7、 Water2.2 Other Standards:ISO/IEC 17025 General Requirements for the Competence of Testing and Calibration Laboratories3ISO 1995 Guide to the Expression of Uncertainty in Measurement3ANSI N42.22 Traceability of Radioactive Sources to the National Institute of Standards and Technology (NIST) andAssoc
8、iatedInstrument Quality Control3ANSI N42.23 Measurement and Associated Instrumentation Quality Assurance for Radioassay Laboratories3ANSI/HPS N13.30 Performance Criteria for Radiobioassay3ISO/IEC 17025 General Requirements for the Competence of Testing and Calibration Laboratories4JCGM 100:2008 Eval
9、uation of Measurement Data Guide to the Expression of Uncertainty in Measurement53. Terminology3.1 Definitions:3.1.1 For definition of other terms used in this practice, refer to Terminology D1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 acceptable verification ratio (AVR)(AVR), nrat
10、io of the difference between measured value of the verification sampleand the known value added to the verification sample to the square root of the sum of the squares of their associated combinedstandard uncertainties. See Eq 10 in 16.2.13.1 This practice is under the jurisdiction ofASTM Committee
11、D19 on Water and is the direct responsibility of Subcommittee D19.04 on Methods of RadiochemicalAnalysis.Current edition approved Dec. 15, 2006June 1, 2014. Published January 2007July 2014. Originally approved in 2006. Last previous edition approved in 2006 as D7282 06. DOI: 10.1520/D7282-06.10.1520
12、/D7282-14.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4 Available from International Organization for Sta
13、ndardization (ISO), 1 rue de Varemb, Case postale 56, CH-1211, Geneva 20, Switzerland, http:/www.iso.ch.3 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.5 Available from American National Standards Institute (ANSI), 25 W
14、. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.Bureau International des Poids etMesures (BIPM), Pavillon de Breteuil F-92312 Svres Cedex France, http:/www.bipm.org/en/publications/guides/gum.html.This document is not an ASTM standard and is intended only to provide the user of an ASTM
15、 standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published b
16、y ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2.1.1 DiscussionSee Eq 10 in 16.2.13.3.2.2 background subtraction count (BSC)(BSC), na source count used to determine the background to
17、 be subtracted fromthe sample test source count.3.2.3 calibrationcalibration, ndetermining the instrument response to a known amount of radioactive material.3.2.4 calibration source (CS)(CS), na known quantity of radioactive material, traceable to a national standards body,prepared for the purpose o
18、f calibrating nuclear instruments.3.2.5 continuing instrument quality controlcontrol, nmeasurements taken to ensure that an instrument responds in the samemanner subsequent to its calibration.3.2.6 instrument check source (ICS)(ICS), na radioactive source, not necessarily traceable to a national sta
19、ndards body, thatis used to confirm the continuing satisfactory operation of an instrument.3.2.7 instrument contamination check (ICC)(ICC), na measurement to determine if a detector is contaminated withradioactivity.3.2.8 instrument quality control chartchart, na chart developed to evaluate the resp
20、onse of an instrument to predetermined,statistically based limits.3.2.9 instrument quality tolerance limitlimit, na limit established to evaluate the acceptable response of an instrument.3.2.10 known value (KV)(KV), nknown value of the analyte activity added to the verification sample. See Eq 7 in 1
21、6.2.11.3.2.10.1 DiscussionSee Eq 7 in 16.2.11.3.2.11 mean, and nstandard deviationsee Practice D4375.3.2.12 measured value (MV)(MV), nmeasured value of the verification sample. See Eq 4 in 16.2.9.3.2.12.1 DiscussionSee Eq 4 in 16.2.9.3.2.13 measurement quality objective (MQO)(MQO), nquantitative or
22、qualitative statement of a performance objective orrequirement for a particular method performance characteristic (1).63.2.14 national standards bodybody, nan organization such as National Institute of Standards and Technology (NIST) oranother similar national standards body that provides standards
23、traceable to BIPM (Bureau International des Poids et Mesures(International Bureau of Weights and Measures). Traceability is accomplished with guidance from ANSI N42.22.3.2.14.1 DiscussionTraceability is accomplished with guidance from ANSI N42.22.3.2.15 quality manual (QM)(QM), na document stating t
24、he management policies, objectives, principles, organizationalstructure and authorities, accountability, and implementation of a laboratorys quality system, to assure the quality of its data.3.2.15.1 DiscussionThe quality manual shall document the process by which appropriate analytical methods are
25、selected, their capability is evaluatedand their performance is documented. The analytical methods manual and standard operating procedure manuals shall be part ofbut not necessarily included in the quality manual. The quality manual or standard operating procedures, or both, shall also includeinstr
26、uctions that prescribe corrective action, for example, in the event of instrument check source (ICS), or instrumentcontamination check (ICC), or background subtraction count (BSC), or a combination thereof, failure.3.2.16 relative standard deviation (RSD)(RSD), nrelative standard deviation of the me
27、an expressed as a percentage (alsoknown as coefficient of variation). See Practice D4375 and 16.2.7.3.2.16.1 Discussion6 The boldface numbers in parentheses refer to the list of references at the end of this standard.D7282 142See Practice D4375 and 16.2.7.3.2.17 sample test source (STS)(STS), na sam
28、ple, sample aliquant, or final product of a chemical or physical processprepared for the purpose of activity determination.3.2.18 standard deviation, nsee Practice D4375.3.2.19 working calibration source (WCS)(WCS), na calibration source (see 3.1.43.2.4), including those diluted or preparedby chemic
29、al procedure for the purpose of calibrating an instrument.3.2 For definition of other terms used in this practice refer to Terminology D1129.3.3 Acronyms:3.3.1 ADCanalog digital conversion3.3.2 AVRacceptable verification ratio3.3.3 BIPMBureau International des Poids et Mesures. Also known as Interna
30、tional Bureau of Weights and Measures.3.3.4 BSCbackground subtraction count3.3.5 CScalibration source3.3.6 DFdecay factor3.3.7 FWHMfull width half maximum3.3.8 ICCinstrument contamination check3.3.9 ICSinstrument check source3.3.10 KVknown value3.3.11 LCSliquid scintillation counter3.3.12 MVmeasured
31、 value3.3.13 MQOmeasurement quality objective3.3.14 NISTNational Institute of Standards and Technology3.3.15 QCquality control3.3.16 QMquality manual3.3.17 RSDrelative standard deviation3.3.18 STSsample test source3.3.19 WCSworking calibration source4. Summary of Practice4.1 This practice summarizes
32、 information and guidance for set-up, calibration and quality control for nuclear countinginstruments. The procedure is divided into four main sections:Introduction Sections 1 through 6Instrument set-up Sections 7 through 9Initial instrument quality controltestingSections 10 through 13Calibration Se
33、ctions 14 through 19Continuing instrument qualitycontrol testingSections 20 through 255. Significance and Use5.1 This practice is consistent with a performance-based approach wherein the frequency of re-calibration and instrument testingis linked to a laboratorys continuing performance with its qual
34、ity control results. Under the premise of this practice, a laboratorydemonstrates that its instrument performance is acceptable for analyzing sample test sources.5.2 When a laboratory demonstrates acceptable performance based on continuing instrument quality control data (that is, QCcharts), batch Q
35、C samples (that is, blanks, laboratory control samples, replicates, matrix spikes, and other batch QC samples asmay be applicable) and independent reference materials, traditional schedule-driven instrument recalibration is permissible butunnecessary.5.3 When continuing instrument QC, batch QC, or i
36、ndependent reference material sample results indicate that instrumentresponse has exceeded established control or tolerance limits, instrument calibration is required. Other actions related to sampleanalyses on the affected instruments may be required by the laboratory QM.5.4 The data obtained while
37、 following this Practice will most likely reside in computer storage. This data remains in thecomputer storage where it is readily retrievable and as necessary is used to produce plots, graphs, spreadsheets and other types ofdisplays and reports. Frequency and performance of data storage backup shou
38、ld be specified in the laboratory QM.D7282 1436. Hazards6.1 The vendor supplied safety instructions and laboratory safety regulations should be consulted before using electronic andelectrical equipment.6.2 Corrosive, flammable, reactive and toxic materials may be used when performing some steps in t
39、his practice. Be cognizantof hazards involved with all materials and processes employed and comply with any and all applicable health and safetyprocedures, plans and regulations. Material Safety Data Sheets are a source of information.INSTRUMENT SET-UP7. Scope7.1 Instructions are provided for initia
40、l set-up of instruments used for activity measurements. These instructions may also beapplied when the operating parameters of an instrument are being reestablished.8. Significance and Use8.1 Successful set-up of an instrument and its subsequent routine use depend, at least in part; on how well the
41、manufacturersinstructions are written and followed. Thus the manufacturers recommendations are an integral part of this process. Success alsodepends on how well the laboratory has planned, developed and documented its own protocol for instrument use and how wellpersonnel are trained.9. Instrument Se
42、t-up9.1 Gas Proportional Counting Initial Instrument Set-up:9.1.1 Upon initial set-up, after major repair or service, or when QC results indicate the need to reestablish operating parametersfor an instrument, measure a suitable calibration source (that is, ICS or WCS) as specified in the laboratory
43、QM and/ormanufacturers protocol to confirm that the instrument responds according to QM or manufacturers specifications. The instrumentset up and initial calibration records should be maintained per applicable record requirements. ISO/IEC 17025 includes informationregarding the type of records to sa
44、ve.retain.9.1.2 If the instrument being configured has previously been used to generate sample test source results, the “as-found”instrument settings (that is, operating voltage and discriminator settings) should be recorded and compared to previous “as-left”parameters to ensure that instrument conf
45、iguration has been maintained. If the instrument configuration has changed, aninvestigation into the potential impact of the changes shall be conducted and appropriate corrective action taken.9.1.3 Establish appropriate instrument operational parameters for the intended measurements. For example, ac
46、quire voltageplateaus and establish the alpha or beta, or both, plateau operating voltages, and alpha or beta, or both, discriminator settings (thatis, adjust for crosstalk). Instrument set up and configuration should be optimized for the intended applications. For example, it maybe desirable to per
47、form voltage plateaus and optimize discriminator settings using a distributed source or a specific radionuclide(for example, a 2-in. 50.8-mm (2-in.) diameter 230Th source as opposed to a point source containing 210Po) when intendedapplications use a different source geometry or radionuclide. If inst
48、rument set-up and configuration deviates from the defaultsrecommended by the manufacturer, the configuration and procedure to be used shall be specified in detail in the laboratory QM.Operating parameters should be established to produce consistency in detection characteristics across multiple detec
49、tors used fora common application. When the instrument operational parameters are satisfactorily established, record the “as-left” instrumentsettings for future reference.9.2 Gamma Spectrometry Initial Instrument Set-up:9.2.1 Upon initial set-up, after major repair or service, or when QC results indicate the need to reestablish operating parametersfor an instrument, measure a suitable calibration source (that is, ICS or WCS) as specified in the laboratory QM and/ormanufacturers protocol to confirm that
