SIST EN ISO 28057:2021
(Main)Clinical dosimetry - Dosimetry with solid thermoluminescence detectors for photon and electron radiations in radiotherapy (ISO 28057:2019)
Clinical dosimetry - Dosimetry with solid thermoluminescence detectors for photon and electron radiations in radiotherapy (ISO 28057:2019)
This document describes 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 polycrystalline 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 polymethyl 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 document applies to dosimetry in teletherapy with both photon radiation from 20 keV to 50 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.
Dosimetrie mit Festkörper - Thermolumineszenzdetektoren für Photonen- und Elektronenstrahlung in der Strahlentherapie (ISO 28057:2019)
Im vorliegenden Dokument werden Regeln für die Verfahren, Anwendungen und Messsysteme der Thermolumineszenzdosimetrie (TL-Dosimetrie, TLD) für Dosismessungen nach der Sondenmethode festgelegt. Sie ist anzuwenden insbesondere für Thermolumineszenz-Detektoren fester Form und Größe, d. h. Stäbchen (en: rods), Scheibchen (en: chips) und Mikrowürfel (en: microcubes), hergestellt aus LiF:Mg,Ti oder LiF:Mg,Cu,P in kristalliner oder polykristalliner Form. Sie ist nicht anzuwenden für LiF in Pulverform; dessen Gebrauch erfordert spezielle Verfahren. Die Sondenmethode beruht darauf, dass einzelne TL-Detektoren oder TL-Sonden, d. h. Sätze von TL-Detektoren, in ein Wasserphantom oder ein wasseräquivalentes Phantom eingebracht werden. Als TL Sonde bezeichnet man die Anordnung eines oder mehrerer TL-Detektoren in einem dünnwandigen Polymethylmethacrylat (PMMA)-Gehäuse.
Das Ziel dieser Regeln ist es, die in der klinischen Dosimetrie am Patienten oder im Phantom unentbehrliche Zuverlässigkeit und Genauigkeit sicherzustellen. Dieses Dokument ist anzuwenden für die Dosimetrie in der Teletherapie mit Photonenstrahlung von 20 keV bis 50 MeV und mit Elektronenstrahlung von 4 MeV bis 25 MeV sowie in der Brachytherapie mit Photonen emittierenden Radionukliden. Diese Anwendungen stellen eine wichtige Ergänzung zur Dosimetrie mit Ionisationskammern dar.
Dosimétrie clinique - Dosimétrie avec détecteurs thermoluminescents solides pour les rayonnements de photons et d'électrons en radiothérapie (ISO 28057:2019)
Le présent document décrit les règles pour les procédures, applications et systèmes de dosimétrie par thermoluminescence (TLD) pour les mesurages de doses conformément à la technique de la sonde. Il s'applique en particulier aux «détecteurs TL» solides, à savoir les bâtonnets, les pastilles et les microcubes fabriqués à partir de LiF:Mg,Ti ou de LiF:Mg,Cu,P sous forme cristalline ou polycristalline. Il ne s'applique pas aux poudres de LiF, étant donné que leur utilisation requiert des procédures spéciales. La technique de la sonde comprend la disposition, en particulier dans un fantôme d'eau ou dans un fantôme équivalant à un tissu, de détecteurs TL uniques ou de «sondes TL», c'est-à-dire des ensembles de détecteurs TL disposés dans des boîtiers de poly(méthacrylate de méthyle) (PMMA) à paroi fine.
Ces règles visent à garantir la fiabilité et l'exactitude indispensables en dosimétrie clinique lorsqu'elle est appliquée sur ou dans le patient ou le fantôme. Le présent document s'applique à la dosimétrie en téléradiothérapie pour le rayonnement de photons entre 20 keV et 50 MeV et le rayonnement d'électrons entre 4 MeV et 25 MeV ainsi qu'en curiethérapie avec des radionucléides émettant des photons. Ces applications sont complémentaires de l'utilisation des chambres d'ionisation.
Klinična dozimetrija - Dozimetrija s trdnimi termoluminiscenčnimi zaznavali pri fotonskih in elektronskih sevanjih v radioterapiji (ISO 28057:2019)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 28057:2021
01-april-2021
Nadomešča:
SIST EN ISO 28057:2018
Klinična dozimetrija - Dozimetrija s trdnimi termoluminiscenčnimi zaznavali pri
fotonskih in elektronskih sevanjih v radioterapiji (ISO 28057:2019)
Clinical dosimetry - Dosimetry with solid thermoluminescence detectors for photon and
electron radiations in radiotherapy (ISO 28057:2019)
Dosimetrie mit Festkörper - Thermolumineszenzdetektoren für Photonen- und
Elektronenstrahlung in der Strahlentherapie (ISO 28057:2019)
Dosimétrie clinique - Dosimétrie avec détecteurs thermoluminescents solides pour les
rayonnements de photons et d'électrons en radiothérapie (ISO 28057:2019)
Ta slovenski standard je istoveten z: EN ISO 28057:2021
ICS:
13.280 Varstvo pred sevanjem Radiation protection
SIST EN ISO 28057:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST EN ISO 28057:2021
---------------------- Page: 2 ----------------------
SIST EN ISO 28057:2021
EN ISO 28057
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2021
EUROPÄISCHE NORM
ICS 13.280 Supersedes EN ISO 28057:2018
English Version
Clinical dosimetry - Dosimetry with solid
thermoluminescence detectors for photon and electron
radiations in radiotherapy (ISO 28057:2019)
Dosimétrie clinique - Dosimétrie avec détecteurs Dosimetrie mit Festkörper -
thermoluminescents solides pour les rayonnements de Thermolumineszenzdetektoren für Photonen- und
photons et d'électrons en radiothérapie (ISO Elektronenstrahlung in der Strahlentherapie (ISO
28057:2019) 28057:2019)
This European Standard was approved by CEN on 18 January 2021.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 28057:2021 E
worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN ISO 28057:2021
EN ISO 28057:2021 (E)
Contents Page
European foreword . 3
2
---------------------- Page: 4 ----------------------
SIST EN ISO 28057:2021
EN ISO 28057:2021 (E)
European foreword
The text of ISO 28057:2019 has been prepared by Technical Committee ISO/TC 85 "Nuclear energy,
nuclear technologies, and radiological protection” of the International Organization for Standardization
(ISO) and has been taken over as EN ISO 28057:2021 by Technical Committee CEN/TC 430 “Nuclear
energy, nuclear technologies, and radiological protection” the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by August 2021, and conflicting national standards shall
be withdrawn at the latest by August 2021.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 28057:2018.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 28057:2019 has been approved by CEN as EN ISO 28057:2021 without any modification.
3
---------------------- Page: 5 ----------------------
SIST EN ISO 28057:2021
---------------------- Page: 6 ----------------------
SIST EN ISO 28057:2021
INTERNATIONAL ISO
STANDARD 28057
Second edition
2019-07
Clinical dosimetry — Dosimetry with
solid thermoluminescence detectors
for photon and electron radiations in
radiotherapy
Dosimétrie clinique — Dosimétrie avec détecteurs
thermoluminescents solides pour les rayonnements de photons et
d'électrons en radiothérapie
Reference number
ISO 28057:2019(E)
©
ISO 2019
---------------------- Page: 7 ----------------------
SIST EN ISO 28057:2021
ISO 28057:2019(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized 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 ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 28057:2021
ISO 28057:2019(E)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Rules for the TLD measurement procedure . 9
4.1 Principle of measurement . 9
4.2 Measured quantity . 9
4.3 Measurement cycle .10
4.3.1 General requirements .10
4.3.2 Sequence of measurement cycles .10
4.3.3 Common passing of the measurement cycles .10
4.3.4 Handling of TL detectors.10
4.3.5 Pre-irradiation annealing .11
4.3.6 Irradiation .11
4.3.7 Post-irradiation annealing.11
4.3.8 Reading.11
4.4 Measurement of the absorbed dose to water .12
4.4.1 Basic formula for the determination of the absorbed dose to water .12
4.4.2 Determination of the background value, M .
0 12
4.4.3 Determination of the indicated value, M .
i 13
4.4.4 Determination of the individual calibration coefficients, N .13
i
4.4.5 Determination of the correction factors, k .15
ν
4.5 Uncertainty of measurement of the absorbed dose .22
4.6 Reusability .23
4.7 Stability check .23
4.8 Staff .23
5 Requirements for the TLD system .23
5.1 General information .23
5.1.1 Classification of the requirements .23
5.1.2 Requirements for operation characteristics .24
5.2 Completeness of the TLD system .24
5.2.1 Technical components.24
5.2.2 Hardware and software components .24
5.2.3 Operating instructions .24
5.2.4 Access to a calibration irradiation device .26
5.3 Requirements for TL detectors .26
5.3.1 Characteristics of TL materials .26
5.3.2 Tailoring of TL materials .26
5.3.3 Reusability of TL detectors .27
5.3.4 Individual variation .27
5.4 Requirements for TL-indicating instruments .28
5.4.1 General remarks .28
5.4.2 Mechanical setup .28
5.4.3 Warm-up time .28
5.4.4 Indication and indication range .28
5.4.5 Background value .28
5.4.6 Overflow indication and effects during evaluation of high doses .28
5.4.7 Test light source .29
5.4.8 Changes in the response .29
5.4.9 Mechanical construction .29
5.4.10 Light shielding . . .29
© ISO 2019 – All rights reserved iii
---------------------- Page: 9 ----------------------
SIST EN ISO 28057:2021
ISO 28057:2019(E)
5.4.11 Climatic influences .29
5.4.12 Electrical requirements .29
5.4.13 Operational safety and detection of function failure .30
5.4.14 Data output and data backup .32
5.5 Requirements for auxiliary instruments (pre-irradiation annealing device) .32
5.5.1 Pre-irradiation annealing .32
5.5.2 Construction .32
5.5.3 Electrical requirements .32
5.5.4 Operation safety .32
5.5.5 Detection of function failure .33
5.5.6 Indication of the operating state .33
5.6 Requirements for the entire TLD system .33
5.6.1 Minimum measuring ranges .33
5.6.2 Minimum rated ranges of use .33
5.6.3 Ranges of test parameters .34
5.7 Requirements for the calibration irradiation device.35
5.8 Requirements for the accompanying papers .35
5.9 Acceptance tests .35
5.9.1 General requirements .35
5.9.2 Number of TL detectors used .36
5.9.3 Type of TL detectors used .36
Bibliography .37
iv © ISO 2019 – All rights reserved
---------------------- Page: 10 ----------------------
SIST EN ISO 28057:2021
ISO 28057:2019(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
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
organizations, 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 further 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 (see www .iso .org/directives).
Attention 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 Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: www .iso .org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 85, Nuclear energy, nuclear technologies,
and radiological protection, Subcommittee SC 2, Radiological protection.
This second edition cancels and replaces the first edition (ISO 28057:2014), which has been technically
revised.
— The clause on terms and definitions and the clause on rules for TLD measurement procedures,
including quality assurance measurements at clinical accelerators, have been complemented and
sharpened to ensure the safe application of TL dosimetry in the radiation therapy of cancer.
— Batch dependent changes of the k values have been correlated with the simultaneously occurring
Q
mass density variations of TL discs (see 4.4.5.5).
— The response of TL materials to the neutrons, occurring within and around photon beams in
megavoltage radiotherapy due to the photonuclear effect and eventually generating considerable
components of the indicated values, has been dealt with in more detail (see 4.4.5.5).
— It is high-lighted that the k values of clinical electron beams are energy independent (see 4.4.5.5).
E
— Recent experimental results concerning the contribution of “intrinsic effects” to the response of TL
detectors have been considered (see 4.4.5.5).
— The French title and the numbering of some subclauses of 5.4 have been corrected; Table 9 has been
equipped with a heading.
© ISO 2019 – All rights reserved v
---------------------- Page: 11 ----------------------
SIST EN ISO 28057:2021
ISO 28057:2019(E)
Introduction
The thermoluminescence dosimetry (TLD) with lithium fluoride (LiF) detectors has several advantages,
in particular:
— small 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 that, prior to each dosimetry
application, they have to be regenerated by a pre-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 the response of these detectors, with sufficiently small
fluctuations of the individually indicated values. From this mean alteration, a correction factor can be
derived.
The essential aim of this document is to specify the procedures and to carry out corrections which
allow one to achieve
[17]
a) a repeatability of the indicated value within a fraction of a percent and thus;
b) a total uncertainty of measurement (including the calibration steps tracing to the primary
[18][31][25][61][62]
standards) of a few percent, as in ionization chamber dosimetry .
The specifications in this document comprise 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 document 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 stated above, this document 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 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
radiation field or in its periphery. A further usage is the quality assurance of clinical dosimetry by
[1][2][10][12][20][22][26][27][55]
postal dose intercomparison .
The role of this document is not to anticipate national or international codes of practice in clinical
dosimetry, neither for external beam therapy, brachytherapy, whole-body irradiation, mammography,
nor dose measurements outside the treatment field or radiation protection of the staff. The authors
of this document are well aware of the wide spectrum of the methods of clinical dosimetry, in which
TL dosimetry is merely occupying a small sector. But within this framework, this document 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
on the TLD system; this document addresses medical physicists as well as 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 other producers. The practical examples given, e.g. for the TL probe calibration conditions and for
the numerical values of correction factor, k , accounting for the dependence of the detector response
Q
on radiation quality, Q, are not conceived to be pre-emptive in relation to more general standards of
the methods of clinical dosimetry or dose intercomparisons. Rather, this document provides access to
the reliable application of TLD methods based upon the published results of worldwide development.
vi © ISO 2019 – All rights reserved
---------------------- Page: 12 ----------------------
SIST EN ISO 28057:2021
ISO 28057:2019(E)
The long-standing experience in the clinical usage of TLD, expressed in a set of valuable textbooks,
[6][13][25][28][29][42][43][61][62][54]
protocols, and recommendations , has been accounted for.
© ISO 2019 – All rights reserved vii
---------------------- Page: 13 ----------------------
SIST EN ISO 28057:2021
---------------------- Page: 14 ----------------------
SIST EN ISO 28057:2021
INTERNATIONAL STANDARD ISO 28057:2019(E)
Clinical dosimetry — Dosimetry with solid
thermoluminescence detectors for photon and electron
radiations in radiotherapy
1 Scope
This document describes 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 polycrystalline 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 polymethyl 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 document applies to dosimetry in
teletherapy with both photon radiation from 20 keV to 50 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 references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 60601-1, Electromedical equipment — Part 1: General instructions pertaining to safety
IEC 61000-4-2, Electromagnetic compatibility (EMV) — Part 4-2: Test and measurement procedure — Test
of immunity against static electric discharges
IEC 61000-4-3, Electromagnetic compatibility (EMC) — Part 4-3: Testing and measurement techniques —
Radiated, radio-frequency, electromagnetic field immunity test
IEC 61000-4-4, Electromagnetic compatibility (EMC) — Part 4-4: Testing and measurement techniques —
Electrical fast transient/burst immunity test
IEC 61000-4-5, Electrom
...
SLOVENSKI STANDARD
oSIST prEN ISO 28057:2020
01-november-2020
Klinična dozimetrija - Dozimetrija s trdnimi termoluminiscenčnimi zaznavali pri
fotonskih in elektronskih sevanjih v radioterapiji (ISO 28057:2019)
Clinical dosimetry - Dosimetry with solid thermoluminescence detectors for photon and
electron radiations in radiotherapy (ISO 28057:2019)
Dosimetrie mit Festkörper - Thermolumineszenzdetektoren für Photonen- und
Elektronenstrahlung in der Strahlentherapie (ISO 28057:2019)
Dosimétrie clinique - Dosimétrie avec détecteurs thermoluminescents solides pour les
rayonnements de photons et d'électrons en radiothérapie (ISO 28057:2019)
Ta slovenski standard je istoveten z: prEN ISO 28057
ICS:
13.280 Varstvo pred sevanjem Radiation protection
oSIST prEN ISO 28057:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
oSIST prEN ISO 28057:2020
---------------------- Page: 2 ----------------------
oSIST prEN ISO 28057:2020
INTERNATIONAL ISO
STANDARD 28057
Second edition
2019-07
Clinical dosimetry — Dosimetry with
solid thermoluminescence detectors
for photon and electron radiations in
radiotherapy
Dosimétrie clinique — Dosimétrie avec détecteurs
thermoluminescents solides pour les rayonnements de photons et
d'électrons en radiothérapie
Reference number
ISO 28057:2019(E)
©
ISO 2019
---------------------- Page: 3 ----------------------
oSIST prEN ISO 28057:2020
ISO 28057:2019(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized 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 ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved
---------------------- Page: 4 ----------------------
oSIST prEN ISO 28057:2020
ISO 28057:2019(E)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Rules for the TLD measurement procedure . 9
4.1 Principle of measurement . 9
4.2 Measured quantity . 9
4.3 Measurement cycle .10
4.3.1 General requirements .10
4.3.2 Sequence of measurement cycles .10
4.3.3 Common passing of the measurement cycles .10
4.3.4 Handling of TL detectors.10
4.3.5 Pre-irradiation annealing .11
4.3.6 Irradiation .11
4.3.7 Post-irradiation annealing.11
4.3.8 Reading.11
4.4 Measurement of the absorbed dose to water .12
4.4.1 Basic formula for the determination of the absorbed dose to water .12
4.4.2 Determination of the background value, M .
0 12
4.4.3 Determination of the indicated value, M .
i 13
4.4.4 Determination of the individual calibration coefficients, N .13
i
4.4.5 Determination of the correction factors, k .15
ν
4.5 Uncertainty of measurement of the absorbed dose .22
4.6 Reusability .23
4.7 Stability check .23
4.8 Staff .23
5 Requirements for the TLD system .23
5.1 General information .23
5.1.1 Classification of the requirements .23
5.1.2 Requirements for operation characteristics .24
5.2 Completeness of the TLD system .24
5.2.1 Technical components.24
5.2.2 Hardware and software components .24
5.2.3 Operating instructions .24
5.2.4 Access to a calibration irradiation device .26
5.3 Requirements for TL detectors .26
5.3.1 Characteristics of TL materials .26
5.3.2 Tailoring of TL materials .26
5.3.3 Reusability of TL detectors .27
5.3.4 Individual variation .27
5.4 Requirements for TL-indicating instruments .28
5.4.1 General remarks .28
5.4.2 Mechanical setup .28
5.4.3 Warm-up time .28
5.4.4 Indication and indication range .28
5.4.5 Background value .28
5.4.6 Overflow indication and effects during evaluation of high doses .28
5.4.7 Test light source .29
5.4.8 Changes in the response .29
5.4.9 Mechanical construction .29
5.4.10 Light shielding . . .29
© ISO 2019 – All rights reserved iii
---------------------- Page: 5 ----------------------
oSIST prEN ISO 28057:2020
ISO 28057:2019(E)
5.4.11 Climatic influences .29
5.4.12 Electrical requirements .29
5.4.13 Operational safety and detection of function failure .30
5.4.14 Data output and data backup .32
5.5 Requirements for auxiliary instruments (pre-irradiation annealing device) .32
5.5.1 Pre-irradiation annealing .32
5.5.2 Construction .32
5.5.3 Electrical requirements .32
5.5.4 Operation safety .32
5.5.5 Detection of function failure .33
5.5.6 Indication of the operating state .33
5.6 Requirements for the entire TLD system .33
5.6.1 Minimum measuring ranges .33
5.6.2 Minimum rated ranges of use .33
5.6.3 Ranges of test parameters .34
5.7 Requirements for the calibration irradiation device.35
5.8 Requirements for the accompanying papers .35
5.9 Acceptance tests .35
5.9.1 General requirements .35
5.9.2 Number of TL detectors used .36
5.9.3 Type of TL detectors used .36
Bibliography .37
iv © ISO 2019 – All rights reserved
---------------------- Page: 6 ----------------------
oSIST prEN ISO 28057:2020
ISO 28057:2019(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
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
organizations, 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 further 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 (see www .iso .org/directives).
Attention 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 Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: www .iso .org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 85, Nuclear energy, nuclear technologies,
and radiological protection, Subcommittee SC 2, Radiological protection.
This second edition cancels and replaces the first edition (ISO 28057:2014), which has been technically
revised.
— The clause on terms and definitions and the clause on rules for TLD measurement procedures,
including quality assurance measurements at clinical accelerators, have been complemented and
sharpened to ensure the safe application of TL dosimetry in the radiation therapy of cancer.
— Batch dependent changes of the k values have been correlated with the simultaneously occurring
Q
mass density variations of TL discs (see 4.4.5.5).
— The response of TL materials to the neutrons, occurring within and around photon beams in
megavoltage radiotherapy due to the photonuclear effect and eventually generating considerable
components of the indicated values, has been dealt with in more detail (see 4.4.5.5).
— It is high-lighted that the k values of clinical electron beams are energy independent (see 4.4.5.5).
E
— Recent experimental results concerning the contribution of “intrinsic effects” to the response of TL
detectors have been considered (see 4.4.5.5).
— The French title and the numbering of some subclauses of 5.4 have been corrected; Table 9 has been
equipped with a heading.
© ISO 2019 – All rights reserved v
---------------------- Page: 7 ----------------------
oSIST prEN ISO 28057:2020
ISO 28057:2019(E)
Introduction
The thermoluminescence dosimetry (TLD) with lithium fluoride (LiF) detectors has several advantages,
in particular:
— small 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 that, prior to each dosimetry
application, they have to be regenerated by a pre-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 the response of these detectors, with sufficiently small
fluctuations of the individually indicated values. From this mean alteration, a correction factor can be
derived.
The essential aim of this document is to specify the procedures and to carry out corrections which
allow one to achieve
[17]
a) a repeatability of the indicated value within a fraction of a percent and thus;
b) a total uncertainty of measurement (including the calibration steps tracing to the primary
[18][31][25][61][62]
standards) of a few percent, as in ionization chamber dosimetry .
The specifications in this document comprise 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 document 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 stated above, this document 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 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
radiation field or in its periphery. A further usage is the quality assurance of clinical dosimetry by
[1][2][10][12][20][22][26][27][55]
postal dose intercomparison .
The role of this document is not to anticipate national or international codes of practice in clinical
dosimetry, neither for external beam therapy, brachytherapy, whole-body irradiation, mammography,
nor dose measurements outside the treatment field or radiation protection of the staff. The authors
of this document are well aware of the wide spectrum of the methods of clinical dosimetry, in which
TL dosimetry is merely occupying a small sector. But within this framework, this document 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
on the TLD system; this document addresses medical physicists as well as 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 other producers. The practical examples given, e.g. for the TL probe calibration conditions and for
the numerical values of correction factor, k , accounting for the dependence of the detector response
Q
on radiation quality, Q, are not conceived to be pre-emptive in relation to more general standards of
the methods of clinical dosimetry or dose intercomparisons. Rather, this document provides access to
the reliable application of TLD methods based upon the published results of worldwide development.
vi © ISO 2019 – All rights reserved
---------------------- Page: 8 ----------------------
oSIST prEN ISO 28057:2020
ISO 28057:2019(E)
The long-standing experience in the clinical usage of TLD, expressed in a set of valuable textbooks,
[6][13][25][28][29][42][43][61][62][54]
protocols, and recommendations , has been accounted for.
© ISO 2019 – All rights reserved vii
---------------------- Page: 9 ----------------------
oSIST prEN ISO 28057:2020
---------------------- Page: 10 ----------------------
oSIST prEN ISO 28057:2020
INTERNATIONAL STANDARD ISO 28057:2019(E)
Clinical dosimetry — Dosimetry with solid
thermoluminescence detectors for photon and electron
radiations in radiotherapy
1 Scope
This document describes 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 polycrystalline 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 polymethyl 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 document applies to dosimetry in
teletherapy with both photon radiation from 20 keV to 50 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 references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 60601-1, Electromedical equipment — Part 1: General instructions pertaining to safety
IEC 61000-4-2, Electromagnetic compatibility (EMV) — Part 4-2: Test and measurement procedure — Test
of immunity against static electric discharges
IEC 61000-4-3, Electromagnetic compatibility (EMC) — Part 4-3: Testing and measurement techniques —
Radiated, radio-frequency, electromagnetic field immunity test
IEC 61000-4-4, 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 compatibility (EMC) — Part 4-6: Testing and measurement techniques —
Immunity to conducted disturbances, induced by radio-frequency fields
IEC 61000-4-8, Electromagnetic compatibility (EMC) — Part 4-8: Testing and measurement techniques —
Power frequency magnetic field immunity test
IEC 61000-4-11, Electromagnetic compatibility (EMC) — Part 4-11: Testing and measurement techniques —
Voltage dips, short interruptions and voltage variations immunity tests
IEC 61187, Electrical and electronic measuring equipment — Documentation
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
© ISO 2019 – All rights reserved 1
---------------------- Page: 11 ----------------------
oSIST prEN ISO 28057:2020
ISO 28057:2019(E)
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
3.1
absorbed dose
energy imparted to matter in a suitably small element of volume by ionizing radiation, divided by the
mass of that element of volume
Note 1 to entry: All statements of absorbed dose need to be completed by a specification of the material for which
the absorbed dose is stated, e.g. absorbed dose to air, D , or absorbed dose to water, D . In this document, the
a w
term absorbed dose, sometimes abbreviated as dose, means the absorbed dose to water, D , if not otherwise
w
specified.
3.2
background value
M
0
indicated value (3.16) of a TLD system (3.46) during evaluation of a
non-irradiated TL detector (3.45) according to the operating instructions
Note 1 to entry: A change in the background value 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).
Note 2 to entry: The background value may also be determined from the average of the individual values
measured with a group of detectors.
3.3
batch
number of TL detectors (3.45) of the same type originating from the same
manufacturing process and corresponding in their entirety both to the requirements defined in this
document 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)
3.4
calibration
determination 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 coefficient (3.5).
Note 2 to entry: The conventional true value of the measured quantity (3.20) by the measured value (3.21)
determined directly or indirectly with a primary standard.
3.5
calibration coefficient
N
i
relation valid under reference conditions (3.32)
D
N =
i
MM−
i 0
in this formula, D is the conventional true value of the measured quantity (3.20), M − M is the difference
i 0
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 is the reciprocal value of the response (3.39) under reference
conditions (3.32).
2 © ISO 2019 – All rights reserved
---------------------- Page: 12 ----------------------
oSIST prEN ISO 28057:2020
ISO 28057:2019(E)
3.6
casing
capsule, usually made from PMMA of 1 mm front wall thickness and shaped as a flat circular cylinder, in
which a small set of TL detectors (3.45) can be placed in the same plane
Note 1 to entry: The setup consisting of the detectors (3.45) and the casing is the TL probe (3.48).
Note 2 to entry: Other forms of the casing may be chosen to fit the respective application, e.g. for intracavitary
measurements or measurements on the patient surface. Low-density materi
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.