1、BSI Standards PublicationBS ISO 28057:2014Dosimetry with solidthermoluminescence detectorsfor photon and electronradiations in radiotherapyBS ISO 28057:2014 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 28057:2014.The UK participation in its preparation was e
2、ntrusted to TechnicalCommittee NCE/2, Radiation protection and measurement.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapp
3、lication. The British Standards Institution 2014. Published by BSI StandardsLimited 2014ISBN 978 0 580 74397 9ICS 13.280Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committe
4、e on 31 March 2014.Amendments issued since publicationDate Text affectedBS ISO 28057:2014 ISO 2014Dosimetry with solid thermoluminescence detectors for photon and electron radiations in radiotherapyDosimtrie avec dtecteurs de thermolumiscence solides pour le photon et rayonnements dlectron en radiot
5、hrapieINTERNATIONAL STANDARDISO28057First edition2014-03-01Reference numberISO 28057:2014(E)BS ISO 28057:2014ISO 28057:2014(E)ii ISO 2014 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2014All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized
6、 otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright of
7、ficeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 28057:2014ISO 28057:2014(E) ISO 2014 All rights reserved iiiContents PageForeword ivIntroduction v1 Scope . 12 Normative references 13 Terms and defini
8、tions . 24 Rules for the TLD measurement procedure . 94.1 Principle of measurement . 94.2 Measured quantity . 94.3 Measurement cycle . 104.4 Measurement of the absorbed dose to water 124.5 Uncertainty of measurement of the absorbed dose .224.6 Reusability . 224.7 Stability check . 234.8 Staff 235 Re
9、quirements for the TLD system .235.1 General information 235.2 Completeness of the TLD system . 235.3 Requirements for TL detectors 265.4 Requirements for TL-indicating instruments .275.5 Requirements for auxiliary instruments (pre-irradiation annealing device) .325.6 Requirements for the entire TLD
10、 system 325.7 Requirements for the calibration irradiation device.355.8 Requirements for the accompanying papers .355.9 Acceptance tests . 35Bibliography .37BS ISO 28057:2014ISO 28057:2014(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standa
11、rds bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organ
12、izations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its f
13、urther maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directive
14、sAttention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introd
15、uction and/or on the ISO list of patent declarations received. www.iso.org/patentsAny trade name used in this document is information given for the convenience of users and does not constitute an endorsement.The committee responsible for this document is ISO/TC 85, Nuclear energy, nuclear technologi
16、es, and radiological protection, Subcommittee SC 2, Radiological protection.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the fol
17、lowing URL: http:/www.iso.org/iso/home/standards_development/resources-for-technical-work/foreword.htmiv ISO 2014 All rights reservedBS ISO 28057:2014ISO 28057:2014(E)IntroductionThe thermoluminescence dosimetry (TLD) with lithium fluoride (LiF) detectors has several advantages, in particular: small
18、 volumes of the detectors; applicability to continuous and pulsed radiation; fair water equivalency of the detector material; few correction factors needed for absorbed dose determinations.The main disadvantage of thermoluminescence (TL) detectors is, however, that they have to be regenerated by a p
19、re-irradiation annealing procedure. Unfortunately, it is not possible to restore the former response of the detectors perfectly by this annealing. Provided, however, that all detectors of a production batch always undergo the same thermal treatment, one can at least determine the mean alteration of
20、the response of these detectors, with sufficiently small fluctuations of the individual values. From this mean alteration, a correction factor can be derived.The essential aim of this International Standard is to specify the procedures and to carry out corrections which allow one to achieve (1) a re
21、peatability of the indicated value within a fraction of a percent17and thus, (2) a total uncertainty of measurement (including the calibration steps tracing to the primary standards) of a few percent, as in ionization chamber dosimetry.1831256162The specifications in this International Standard comp
22、rise special terms used in TLD, rules for the measurement technique, and requirements for the measurement system. The defined requirements and the testing techniques can, in whole or in part, serve as a basis for stability checks and acceptance tests. The TLD procedures described in this Internation
23、al Standard can be used for photon radiation within the energy range from 20 keV to 50 MeV, including photon brachytherapy, and for electron radiation within the energy range from 4 MeV to 25 MeV, excluding beta radiation brachytherapy. In order to achieve the repeatability and total uncertainty sta
24、ted above, this International Standard is applicable in the dose range above 1 mGy. The upper limit of the minimum measuring range is in the order of magnitude of 10 Gy to 100 Gy. In clinical dosimetry, TL detectors are applied taking into account the requirements of high spatial resolution, i.e. in
25、 the study of the dose distributions with high gradients occurring in small stereotactic radiation fields and around brachytherapy sources. The other common application is the measurement of dose distributions in large absorbers, e.g. geometrical or tissue equivalent phantoms, either within the radi
26、ation field or in its periphery. A further usage is the quality assurance of clinical dosimetry by postal dose intercomparison.1210122022262755The role of this International Standard is not to anticipate national or international codes of practice in clinical dosimetry, neither for external beam the
27、rapy, brachytherapy, whole-body irradiation, mammography, nor dose measurements outside the treatment field or radiation protection of the staff. The authors of this International Standard are well aware of the wide spectrum of the methods of clinical dosimetry, in which TL dosimetry is merely occup
28、ying a small sector. But within this framework, this International Standard provides reliable concepts and rules for good practice for the application of TLD methods. The items covered include the terms and definitions, the rules for TLD measurement procedures, and the requirements for the TLD syste
29、m; this International Standard also addresses medical physicists and instrument producers. Notably, the numerical examples given are valid for the TL detector materials and products stated in the publications referred to, and tests may be necessary to check whether they apply to TLD materials of oth
30、er producers. The practical examples given, e.g. for the TL probe calibration conditions and for the numerical values of correction factor, kQ, accounting for the dependence of the detector response on radiation quality, Q, are not conceived to be preemptive in relation to more general standards of
31、the methods of clinical dosimetry or of dose intercomparisons. Rather, this International Standard provides access to the reliable application of TLD methods based upon the published results of worldwide development. The long-standing experience in the clinical usage of TLD, expressed in a set of va
32、luable textbooks, protocols, and recommendations,6132528294243616254has been accounted for. ISO 2014 All rights reserved vBS ISO 28057:2014BS ISO 28057:2014Dosimetry with solid thermoluminescence detectors for photon and electron radiations in radiotherapy1 ScopeThis International Standard describes
33、 rules for the procedures, applications, and systems of thermoluminescence dosimetry (TLD) for dose measurements according to the probe method. It is particularly applicable to solid “TL detectors”, i.e. rods, chips, and microcubes, made from LiF:Mg,Ti or LiF:Mg,Cu,P in crystalline or polycrystallin
34、e form. It is not applicable to LiF powders because their use requires special procedures. The probe method encompasses the arrangement, particularly in a water phantom or in a tissue-equivalent phantom, of single TL detectors or of “TL probes”, i.e. sets of TL detectors arranged in thin-walled poly
35、methyl methacrylate (PMMA) casings.The purpose of these rules is to guarantee the reliability and the accuracy indispensable in clinical dosimetry when applied on or in the patient or phantom. This International Standard applies to dosimetry in teletherapy with both photon radiation from 20 keV to 5
36、0 MeV and electron radiation from 4 MeV to 25 MeV, as well as in brachytherapy with photon-emitting radionuclides. These applications are complementary to the use of ionization chambers.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document an
37、d are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ICRU 60, Fundamental Quantities and Units for Ionizing Radiation (1998)ICRU 62, Prescribing, recordi
38、ng and reporting photon beam therapy. International Commission on Radiation Units and Measurements (1999)IEC 60050-88, IEV: International Electrotechnical Vocabulary. Radiology and radiological physics.IEC 60601-1, Electromedical equipment Part 1: General instructions pertaining to safetyIEC 61000-4
39、-2, Electromagnetic compatibility (EMV) Part 4-2: Test and measurement procedure; Test of immunity against static electric dischargesIEC 61000-4-3, Electromagnetic compatibility (EMC) Part 4-3: Testing and measurement techniques - Radiated, radio-frequency, electromagnetic field immunity test IEC 61
40、000-4-4, Electromagnetic compatibility (EMC) - Part 4-4: Testing and measurement techniques - Electrical fast transient/burst immunity test IEC 61000-4-5, Electromagnetic compatibility (EMC) Part 4-5: Testing and measurement techniques - Surge immunity test IEC 61000-4-6, Electromagnetic compatibili
41、ty (EMC) Part 4-6: Testing and measurement techniques - Immunity to conducted disturbances, induced by radio-frequency fieldsIEC 61000-4-8, Electromagnetic compatibility (EMC) Testing and measurement techniques - Power frequency magnetic field immunity test IEC 61000-4-11, Testing and measurement te
42、chniques - Voltage dips, short interruptions and voltage variations immunity testsINTERNATIONAL STANDARD ISO 28057:2014(E) ISO 2014 All rights reserved 1BS ISO 28057:2014ISO 28057:2014(E)IEC 61000-6-2, Electromagnetic compatibility (EMC) Part 6-2: Generic standards - Immunity for industrial environm
43、entsIEC 61187, Electrical and electronic measuring equipment DocumentationISO/IEC Guide 98-3, Uncertainty of measurement Part 3: Guide to the expression of uncertainty in measurement (GUM:1995)3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1abso
44、rbed doseenergy imparted to matter in a suitably small element of volume by ionizing radiation, divided by the mass of that element of volume3.2background valueM0indicated value (3.16) of a TLD system (3.46) during evaluation of a non-irradiated TL detector (3.45) according to the operating instruct
45、ionsNote 1 to entry: A change in the background value (3.2) can be caused by a change in the TL-indicating instrument (3.47), by an insufficient pre-irradiation annealing (3.28), or by contamination of the detector (3.45).3.3batchnumber of TL detectors (3.45) of the same type originating from the sa
46、me manufacturing process and corresponding in their entirety both to the requirements defined in this International Standard and to the quality properties guaranteed by the manufacturer with regard to their response (3.39), their individual variation (3.17), and their nonlinearity (3.24)3.4calibrati
47、ondetermination of the correlation between the indicated value (3.16) of a TL detector (3.45) and the conventional true value of the measured quantity (3.20), absorbed dose (3.1) to water, under reference conditions (3.32)Note 1 to entry: Calibration serves to determine or check the calibration coef
48、ficient (3.5). The conventional true value of the measured quantity (3.20) is given by the measured value (3.21) determined directly or indirectly with a primary standard.3.5calibration coefficientNirelation valid under reference conditions (3.32)NDMMi=i 0in this formula, D is the conventional true
49、value of the measured quantity (3.20), Mi M0is the difference resulting from the indicated value (3.16) of a single TL detector (3.45)i and the background value (3.2)Note 1 to entry: Thus, the calibration coefficient (3.5) is the reciprocal value of the response (3.39) under reference conditions (3.32).2 ISO 2014 All rights reservedBS ISO 28057:2014ISO 28057:2014(E)3.6casingcapsule, usually made from PMMA of 1 mm front wall thickness and shaped as a flat circular cylinder, in which a sm
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