1、ISO/ASTM 51205:2009(E)ISO/ASTM 51205 2017(E)Standard Practice forUse of a Ceric-Cerous Sulfate Dosimetry System1This standard is issued under the fixed designation ISO/ASTM 51205; the number immediately following the designation indicates theyear of original adoption or, in the case of revision, the
2、 year of last revision.1. Scope1.1 This practice covers the procedures for preparation, testing, and procedure for using the ceric-cerous sulfate dosimetrysystem to determinemeasure absorbed dose (in terms of absorbed dose to water) in materials irradiated by photons (gammaradiation or X-radiation/b
3、remsstrahlung) or high-energy electrons. to water when exposed to ionizing radiation. The systemconsists of a dosimeter and appropriate analytical instrumentation. For simplicity, the system will be referred to as the ceric-ceroussystem. It The ceric-cerous dosimeter is classified as a referencestan
4、dard dosimetry system (see ISO/ASTM Guidetype 1dosimeter on the basis 51261). Ceric-cerous dosimeters are also used as transferstandard dosimeters or routine dosimeters.of theeffect of influence quantities. The ceric-cerous system may be used as a reference standard dosimetry system or as a routined
5、osimetry system.1.2 This document is one of a set of standards that provides recommendations for properly implementing dosimetry in radiationprocessing, and describes a means of achieving compliance with the requirements of ISO/ASTM Practice 52628 for theceric-cerous system. It is intended to be rea
6、d in conjunction with ISO/ASTM Practice 52628.1.3 This practice describes both the spectrophotometric and the potentiometric readout procedures for the ceric-cerous system.1.4 This practice applies only to gamma radiation, X-radiation/bremsstrahlung, and high energy electrons.1.5 This practice appli
7、es provided the following conditions are satisfied:1.5.1 The absorbed-dose range is between 0.5 and 50from 5 102 kGy to 5 104 Gy (1).21.5.2 The absorbed-dose rate is less thandoes not exceed 106 Gy s1 (1).1.5.3 For radionuclide gamma-ray sources, the initial photon energy is greater than 0.6 MeV. Fo
8、r bremsstrahlung photons, theinitial energy of the electrons used to produce the bremsstrahlung photons is equal to or greater than 2 MeV. For electron beams,the initial electron energy is greater than 8 MeV.NOTE 1The lower energy limits are appropriate for a cylindrical dosimeter ampoule of 12-mm d
9、iameter. Corrections for dose gradientsgradient acrossan ampoule of that diameter or less are not required for photons, but the ampoule may be required for electron beams (2). The ceric-cerous system maybe used at lower energies by employing thinner (in the beam direction) dosimeters.dosimeters (see
10、 ICRU Report 35).1.5.4 The irradiation temperature of the dosimeter is above 0C and below 62C (3).NOTE 2The temperature dependencecoefficient of dosimeter response is known only in this range (see 4.35.2). Use outside this range requiresdetermination of the temperature dependence.coefficient.1.6 Thi
11、s 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 establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.1.7 This international s
12、tandard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.1 Th
13、is guidepractice is under the jurisdiction of ASTM Committee E61 on Radiation Processing and is the direct responsibility of Subcommittee E61.02 on DosimetrySystems, and is also under the jurisdiction of ISO/TC 85/WG 3.Current edition approved June 18, 2008. Published June 2009.March 8, 2017. Publis
14、hed May 2017. Originally published asASTM E120588. Last previousASTM editionE120599. ASTM E120593 was adopted by ISO in 1998 with the intermediate designation ISO 15555:1998(E). The present International Standard ISO/ASTM51205:2009(E)51205:2017(E) is a major revision of ISO/ASTM 51205-2002(E) which
15、replaced ISO 15555.51205-2009(E). DOI:10.1520/ISOASTM51205-17.2 The boldface numbers in parentheses refer to the bibliography at the end of this standard.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to
16、 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 by ASTM is to be considered the official document. ISO/AST
17、M International 2017 All rights reserved12. Referenced documents2.1 ASTM Standards:3C912 Practice for Designing a Process for Cleaning Technical GlassesE170 Terminology Relating to Radiation Measurements and DosimetryE178 Practice for Dealing With Outlying ObservationsE275 Practice for Describing an
18、d Measuring Performance of Ultraviolet and Visible SpectrophotometersE666 Practice for Calculating Absorbed Dose From Gamma or X RadiationE668 Practice for Application of Thermoluminescence-Dosimetry (TLD) Systems for Determining Absorbed Dose inRadiation-Hardness Testing of Electronic DevicesE925 P
19、ractice for Monitoring the Calibration of Ultraviolet-Visible Spectrophotometers whose Spectral Bandwidth does notExceed 2 nmE958 Practice for Estimation of the Spectral Bandwidth of Ultraviolet-Visible Spectrophotometers2.2 ISO/ASTM Standards:351261 GuidePractice for Selection and Calibration of Ro
20、utine Dosimetry Systems for Radiation Processing51707 Guide for Estimation of Measurement Uncertainty in Dosimetry for Radiation Processing5140052628 Practice for Characterization and Performance of a High-Dose Radiation Dosimetry Calibration LaboratoryDo-simetry in Radiation Processing5170752701 Gu
21、ide for Estimating Uncertainties in Dosimetry for Performance Characterization of Dosimeters and DosimetrySystems for Use in Radiation Processing2.3 ISO Standards:412749-4 Nuclear energy Vocabulary Part 4: Dosimetry for radiation processing2.4 ISO/IEC Standards:417025 General Requirements for the Co
22、mpetence of Testing and Calibration Laboratories2.5 Joint Committee for Guides in Metrology (JCGM) Reports:JCGM 100:2008, GUM 1995, with minor corrections, Evaluation of measurement data Guide to the Expression of Uncertaintyin Measurement5JCGM 200:2012 (JCGM 200:2008 with minor revisions),VIM, Inte
23、rnational Vocabulary of Metrology Basis and GeneralConcepts and Associated Terms62.6 International Commission on Radiation Units and Measurements (ICRU) Reports:7ICRU Report 1410b (NBS Handbook 85) Radiation Dosimetry: X-Rays and Gamma Rays with Maximum Photon EnergiesBetween 0.6 and 60 MeVPhysical
24、Aspects of IrradiationICRU Report 34 The Dosimetry of Pulsed RadiationICRU Report 35 Radiation Dosimetry: Electrons Electron Beams with Initial Energies Between 1 and 50 MeVICRU Report 3780 Stopping Powers for Electrons and PositronsDosimetry Systems for Use in Radiation ProcessingICRU Report 6085a
25、RadiationFundamental Quantities and Units for Ionizing Radiation3. Terminology3.1 Definitions:3.1.1 calibrationapproved laboratoryset of operations under specified conditions, which establishes the relationshipbetween values indicated by a measuring instrument or measuring system, and the correspond
26、ing values realized by standardstraceable to a nationally or internationally recognized laboratory.laboratory that is a recognized national metrology institute, or hasbeen formally accredited to ISO/IEC 17025, or has a quality system consistent with the requirements of ISO/IEC 17025.3.1.1.1 Discussi
27、onCalibration conditions include environmental and irradiation conditions present during irradiation, storage and measurement of thedosimeters that are used for the generation of a calibration curve. To achieve stable environmental conditions, it may be necessaryto condition the dosimeters before pe
28、rforming the calibration procedure.A recognized national metrology institute or othercalibration laboratory accredited to ISO/IEC 17025 should be used in order to ensure traceability to a national or international3 For referenced ASTM and ISO/ASTM standards, visit the ASTM website, www.astm.org, or
29、contact ASTM Customer Service at serviceastm.org. For Annual Bookof ASTM Standards volume information, refer to the standards Document Summary page on the ASTM website.4 Available from International Organization for Standardization (ISO), ISO Central Secretariat, BIBC II, Chemin de Blandonnet 8, CP
30、401, 1214 Vernier, Geneva,Switzerland, http:/www.iso.org.5 Document produced by Working Group 1 of the Joint Committee for Guides in Metrology (JCGM WG1), Available free of charge at the BIPM website(http:/www.bipm.org).6 Document produced by Working Group 2 of the Joint Committee for Guides in Metr
31、ology (JCGM WG2), Available free of charge at the BIPM website(http:/www.bipm.org).7 Available from International Commission on Radiation Units and Measurements, 7910 Woodmont Ave., Suite 800, Bethesda, MD 20814, USA.ISO/ASTM 51205:2017(E)2 ISO/ASTM International 2017 All rights reservedstandard. A
32、calibration certificate provided by a laboratory not having formal recognition or accreditation will not necessarily beproof of traceability to a national or international standard.3.1.2 calibration curvegraphical representation of the dosimetry systems response function.3.1.2 ceric-cerous dosimeter
33、specially prepared solution of ceric sulfate and cerous sulfate in sulfuric acid, individually sealedin an appropriate container such as a glass ampoule, where the radiation-induced changes in electropotential or optical absorbanceof the solution are related to absorbed dose to water.3.1.4 measureme
34、nt quality assurance plandocumented program for the measurement process that ensures that the expandeduncertainty consistently meets the requirements of the specific application. This plan requires traceability to nationally orinternationally recognized standards.3.1.3 molar linear absorption coeffc
35、ient, mconstant relating the spectrophotometric absorbance, A, of an optically absorbingmolecular species at a given wavelength, , per unit pathlength, d, to the molar concentration, c, of that species in solution:m5 Adc (1)SI unit: m2 mol13.1.3.1 DiscussionThe measurement is sometimes expressed in
36、units of L mol1 cm1.3.1.6 net absorbance, Achange in measured optical absorbance at a selected wavelength determined as the absolutedifference between the pre-irradiation absorbance, Ao, and the post-irradiation absorbance, A, as follows:A 5?A 2Ao? (2)3.1.4 radiation chemical yield, G(x)quotient of
37、n(x) by , where n(x) is the mean amount of a specified entity, x, produced,destroyed, or changed by the mean energy, , imparted to the matter.Gx!5nx! (2)SI unit: mol J13.1.5 reference standard dosimetry systemdosimetry system, generally having the highest metrological quality available at agiven loc
38、ation or in a given organization, from which measurements made there are derived.3.1.6 referencestandard type 1 dosimeterdosimeter of high metrological quality used as a standard to provide measurementstraceable to measurements made using primarystandard dosimeters.quality, the response of which is
39、affected by individualinfluence quantities in a well-defined way that can be expressed in terms of independent correction factors.3.1.9 response functionmathematical representation of the relationship between dosimeter response and absorbed dose, for agiven dosimetry system.3.1.10 routine dosimeterd
40、osimeter calibrated against a primary, reference, or transferstandard dosimeter and used forroutine absorbed-dose measurements.3.1.11 transferstandard dosimetera dosimeter, often a referencestandard dosimeter suitable for transport between differentlocations, used to compare absorbed-dose measuremen
41、ts.3.2 Definitions of Terms Specific to This Standard:3.2.1 electropotential, Edifference in potential between the solutions in the two compartments of an electrochemical cell,measured in millivolts.3.3 For definitions Definitions of other terms used in this practice that pertain to radiation measur
42、ement and dosimetry, refer toASTM Terminologydosimetry may be found in E170. Definitions in ISO 12749-4, ASTM Terminology E170 are compatible withICRU 60; that document, , ICRU 85a, and VIM; these documents, therefore, may be used as an alternative reference.references.4. Significance and use4.1 The
43、 ceric-cerous system provides a reliable means for determining absorbed dose to water. It is based on a process ofreduction of ceric ions to cerous ions in acidic aqueous solution by ionizing radiation (1, 4)., ICRU Report 80).NOTE 3The ceric-cerous system described in the practice has cerous sulfat
44、e added to the initial solution to reduce the effect of organic impuritiesand to allow the potentiometric method of measurement. Other systems used for dosimetry include solutions of ceric sulfate or ceric ammonium sulfatein sulfuric acid without the initial addition of cerous sulfate. These other s
45、ystems are based on the same process of reduction of ceric ions to cerous ionsbut are not included in this practice.4.2 The dosimeter is a solution of ceric sulfate and cerous sulfate in sulfuric acid in an appropriate container such as aflame-sealed glass ampoule. The solution indicates a level of
46、absorbed dose by a change (decrease) in optical absorbance at aISO/ASTM 51205:2017(E)3 ISO/ASTM International 2017 All rights reservedspecified wavelength in the ultraviolet region, or a change (increase) in electropotential. A calibrated spectrophotometer is usedto determine the absorbance and a po
47、tentiometer, with a specially designed cell, is used to determine the electropotential inmillivolts.4.3 The dosimeter response has an irradiation temperature dependence since the radiation chemical yield ( GCe31! ) dependson temperature. The dependence of GCe31! is approximately equal to 0.2 % per d
48、egree Celsius between 0 and 62C (3, 5, 6). Thisirradiation temperature dependence has a slight dependence on the initial cerous ion concentration (see 10.6.3).4.4 The absorbed dose to materials other than water when irradiated under equivalent conditions may be calculated. Proceduresfor making such
49、calculations are given in ASTM Practices E666 and E668 and ISO/ASTM Guide 51261.NOTE 4For a comprehensive discussion of various dosimetry methods applicable to the radiation types and energies discussed in this practice, seeICRU Reports 14, 34, 35, and 37.5. Effect of influence quantities5.1 Guidance on the determination of the performance characteristics of dosimeters and dosimetry systems can be found inASTM Guide 52701. The relevant quantities that need to be considered when using the ceric-cerous dosi
