ISO/ASTM 52628:2020

Standard practice for dosimetry in radiation processing

This practice describes the basic requirements that apply when making absorbed dose measurements in accordance with the ASTM E61 series of dosimetry standards. In addition, it provides guidance on the selection of dosimetry systems and directs the user to other standards that provide specific information on individual dosimetry systems, calibration methods, uncertainty estimation and radiation processing applications. This practice applies to dosimetry for radiation processing applications using electrons or photons (gamma- or X-radiation). This practice addresses the minimum requirements of a measurement management system, but does not include general quality system requirements. This practice does not address personnel dosimetry or medical dosimetry. This practice does not apply to primary standard dosimetry systems. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

Pratique standard pour dosimétrie au traitement par irradiation

General Information

• Status: Published
• Publication Date: 31-Mar-2020
• ICS: 17.240 - Radiation measurements
• Technical Committee: ISO/TC 85 - Nuclear energy, nuclear technologies, and radiological protection
• Drafting Committee: ISO/TC 85 - Nuclear energy, nuclear technologies, and radiological protection
• Current Stage: 6060 - International Standard published
• Start Date: 01-Apr-2020
• Due Date: 03-Apr-2021
• Completion Date: 01-Apr-2020

Relations

• Revises: ISO/ASTM 52628:2013 - Standard practice for dosimetry in radiation processing
• Effective Date: 23-Apr-2020

Standards Content (Sample)

INTERNATIONAL ISO/ASTM
STANDARD 52628
Second edition
2020-04
Standard practice for dosimetry in
radiation processing
Pratique standard pour dosimétrie au traitement par irradiation
Reference number
ISO/ASTM 52628:2020(E)
©
ISO/ASTM International 2020

---------------------- Page: 1 ----------------------
ISO/ASTM 52628:2020(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO/ASTM International 2020
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. In the United States, such requests should be sent to ASTM International.
ISO copyright office ASTM International
CP 401 • Ch. de Blandonnet 8 100 Barr Harbor Drive, PO Box C700
CH-1214 Vernier, Geneva West Conshohocken, PA 19428-2959, USA
Phone: [phone] Phone: [phone]
Fax: [phone] Fax: [phone]
Email: [e-mail] Email: [e-mail]
Website: www.iso.org Website: www.astm.org
Published in Switzerland
ii © ISO/ASTM International 2020 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/ASTM 52628:2020(E)
Contents Page
1 Scope. 2
2 Referenced documents. 2
3 Terminology. 3
4 Significance and use. 4
5 Dosimetry system requirements. 4
6 Classification. 4
7 Guidance. 6
8 Keywords. 8
Annex. 9
Table 1 Examples of type I dosimeters. 5
Table 2 Examples of type II dosimeters. 6
Table 3 General dosimetry requirements for all radiation processing applications. 6
Table 4 Dosimetry requirements for specific radiation processing applications. 6
Table 5 Guidance for dosimetry in specific radiation processing applications. 7
Table 6 Guidance on absorbed-dose mapping and mathematical methods. 7
Table A1.1 Summary of characteristics of dosimeters described in ASTM and ISO/ASTM
radiation processing standards. 10
© ISO/ASTM International 2020 – All rights reserved iii

---------------------- Page: 3 ----------------------
ISO/ASTM 52628:2020(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 (see www.iso.org/directives).
ASTM International is one of the world’s largest voluntary standards development organizations with
global participation from affected stakeholders. ASTM technical committees follow rigorous due process
balloting procedures.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO and ASTM International 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 of 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
www.iso.org/iso/foreword.html.
This document was prepared by ASTM Committee E61, Radiation processing (as ASTM E2628-09), and
drafted in accordance with its editorial rules. It was assigned to Technical Committee ISO/TC 85, Nuclear
energy, nuclear technologies and radiation protection, and adopted under the “fast-track procedure”.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv © ISO/ASTM International 2020 – All rights reserved

---------------------- Page: 4 ----------------------
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
ISO/ASTM 52628:2020(E)
Standard Practice for
1
Dosimetry in Radiation Processing
This standard is issued under the fixed designation ISO/ASTM 52628; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision.
INTRODUCTION
The use of ionizing radiation for the treatment of commercial products such as the sterilization of
healthcare products, the reduction of microbial contamination in food or the modification of polymers
is referred to as radiation processing. The types of radiation used may be gamma radiation (typically
from cobalt-60 sources), X-radiation or accelerated electrons.
In some applications, it is necessary to ensure that the specified absorbed dose is applied. In these
cases, the absorbed dose must be measured, and measurement systems have been developed for this
purpose. Much of the development of these systems rests on the early development of dosimetry
systems for personnel radiation protection and for medical treatment. However, the absorbed doses
used in radiation processing are generally higher, ranging from ~10 Gy up to 100 kGy or more and
new dosimetry systems have been developed for measurements of these doses.
Note that the terms “dose” and “absorbed dose” are used interchangeably in this standard (see
3.1.1).
The dose measurements required in radiation processing concern characterization of radiation
facilities in installation qualification (IQ) and operational qualification (OQ), measurement of dose
distribution in irradiated products in performance qualification (PQ) and routine monitoring of the
irradiation process.
The literature is abundant with articles on dosimeters for radiation processing, and guidelines and
standards have been written by several organizations (the International Atomic Energy Agency
(IAEA) and the International Commission on Radiation Units and Measurements (ICRU), for
example) for the operation of the dosimetry systems and for their use in the characterization and
validationoftheradiationprocessingapplications.Inparticular,ICRUReport80providesinformation
on the scientific basis and historical development of many of the systems in current use.
ASTM Subcommittee E10.01 on Radiation Processing: Dosimetry andApplications was formed in
1984 initially with the scope of developing standards for food irradiation, but its scope was widened
to include all radiation processing applications.The subcommittee, now Committee E61, has under its
jurisdiction approximately 30 standard practices and standard guides, collectively known as the E61
standards on radiation processing. A number of these standards have been published as ISO/ASTM
standards, thereby ensuring a wider international acceptance. These practices and guides describe the
dosimetry systems most commonly used in radiation processing, and the dose measurements that are
required in the validation and routine monitoring of the radiation processes. A current list of the E61
standards on radiation processing is given in 2.1 and 2.2.
The development, validation and routine control of a radiation process comprise a number of
activities, most of which rely on the ability to measure the delivered dose accurately. It is therefore
necessary that dose is measured with traceability to national, or international, standards, and the
uncertainty in measured dose is known, including the effect of influence quantities.The E61 standards
on radiation processing dosimetry serve to fulfill these requirements.
The practices describing dosimetry systems have several common attributes, and there is a need to
have one general standard that can act as a common reference and that can be used as a basis for the
selection of dosimetry systems for defined tasks. ISO/ASTM Practice 52628 serves this purpose. It
outlines general requirements for the calibration and use of dosimetry systems and for the estimation
of measurement uncertainties. Details relating to each dosimetry system are found in the respective
standards and each of these refer to ISO/ASTM Practice 52628 for the general requirements.
© ISO/ASTM International 2020 – All rights reserved
1

---------------------- Page: 5 ----------------------
ISO/ASTM 52628:2020(E)
1. Scope 51261 Practice for Calibration of Routine Dosimetry Sys-
tems for Radiation Processing
1.1 Thispracticedescribesthebasicrequirementsthatapply
51275 Practice for Use of a Radiochromic Film Dosimetry
when making absorbed dose measurements in accordance with
System
the ASTM E61 series of dosimetry standards. In addition, it
51276 Practice for Use of a Polymethylmethacrylate Dosim-
provides guidance on the selection of dosimetry systems and
etry System
directs the user to other standards that provide specific infor-
51310 Practice for Use of a Radiochromic Optical Wave-
mation on individual dosimetry systems, calibration methods,
guide Dosimetry System
uncertainty estimation and radiation processing applications.
51401 Practice for Use of a Dichromate Dosimetry System
1.2 This practice applies to dosimetry for radiation process-
51538 Practice for Use of the Ethanol-Chlorobenzene Do-
ing applications using electrons or photons (gamma- or
simetry System
X-radiation).
51540 Practice for Use of a Radiochromic Liquid Dosimetry
System
1.3 This practice addresses the minimum requirements of a
measurement management system,butdoesnotincludegeneral 51607 Practice for Use of an Alanine-EPR Dosimetry Sys-
tem
quality system requirements.
51608 Practice for Dosimetry in an X-Ray (Bremsstrahlung)
1.4 This practice does not address personnel dosimetry or
Facility for Radiation Processing at Energies between 50
medical dosimetry.
keV and 7.5 MeV
1.5 This practice does not apply to primary standard dosim-
51631 Practice for Use of Calorimetric Dosimetry Systems
etry systems.
for Electron Beam Dose Measurements and Dosimetry
1.6 This standard does not purport to address all of the System Calibration
safety concerns, if any, associated with its use. It is the 51649 Practice for Dosimetry in an Electron Beam Facility
responsibility of the user of this standard to establish appro- for Radiation Processing at Energies Between 300 keV
priate safety, health, and environmental practices and deter- and 25 MeV
mine the applicability of regulatory limitations prior to use. 51650 Practice for Use of a Cellulose Triacetate Dosimetry
System
2. Referenced documents 51702 Practice for Dosimetry in a Gamma Facility for
2 Radiation Processing
2.1 ASTM Standards:
51707 Guide for Estimation of Measurement Uncertainty in
E2232 Guide for Selection and Use of Mathematical Meth-
Dosimetry for Radiation Processing
ods for Calculating Absorbed Dose in Radiation Process-
51818 Practice for Dosimetry in an Electron Beam Facility
ing Applications
for Radiation Processing at Energies Between 80 and 300
E3083 Terminology Relating to Radiation Processing: Do-
keV
simetry and Applications
51900 Guide for Dosimetry in Radiation Research on Food
F1355 GuideforIrradiationofFreshAgriculturalProduceas
and Agricultural Products
a Phytosanitary Treatment
51939 Practice for Blood Irradiation Dosimetry
F1356 Guide for Irradiation of Fresh, Frozen or Processed
51940 Guide for Dosimetry for Sterile Insect Release
Meat and Poultry to Control Pathogens and Other Micro-
Programs
organisms
51956 PracticeforUseofaThermoluminescence-Dosimetry
F1736 Guide for Irradiation of Finfish and Aquatic Inverte-
(TLD) System for Radiation Processing
brates Used as Food to Control Pathogens and Spoilage
52116 Practice for Dosimetry for a Self-Contained Dry-
Microorganisms
Storage Gamma Irradiator
F1885 Guide for Irradiation of Dried Spices, Herbs, and
52303 Guide for Absorbed Dose Mapping in Radiation
Vegetable Seasonings to Control Pathogens and Other
Processing Facilities
Microorganisms
52701 Guide for Performance Characterization of Dosim-
2
2.2 ISO/ASTM Standards:
eters and Dosimetry Systems for Use in Radiation Pro-
51026 Practice for Using the Fricke Dosimetry System
cessing
51205 Practice for Use of a Ceric-Cerous Sulfate Dosimetry
3
2.3 ISO Standards:
System
ISO 11137-1 Sterilization of health care products – Radia-
tion – Part 1: Requirements for development, validation
1
This practice is under the jurisdiction of ASTM Committee E61 on Radiation and routine control of a sterilization process for medical
devices
Processing and is the direct responsibility of Subcommittee E61.01 on Dosimetry,
ISO 11137-3 Sterilization of health care products – Radia-
and is also under the jurisdiction of ISO/TC 85/WG 3.
Current edition approved September 2019. Published April 2020. Originally
tion – Part 3: Guidance on dosimetric aspects of
published as ASTM E2628-09. The present International Standard ISO/ASTM
52628–2020(E) replaces ISO/ASTM 52628–13.
2
For referenced ASTM and ISO/ASTM standards, visit the ASTM website,
3
Available from International Organization for Standardization (ISO), 1, ch. de
www.astm.org, or contact ASTM Customer Service at [e-mail]. For
la Voie-Creuse, Case postale 56, CH-1211, Geneva 20, Switzerland, https://
Annual Book of ASTM Standards volume information, refer to the standard’s
www.iso.org/contact-iso.html
Document Summary page on the ASTM website.
© ISO/ASTM International 2020 – All rights reserved
2

---------------------- Page: 6 ----------------------
ISO/ASTM 52628:2020(E)
development, validation and routine control effect of influence quantities, for a dosimeter or dosimetry
ISO 10012 Measurement managements systems – Require- system under defined test conditions.
ments for measurement processes and measuring equip-
3.1.6 dosimeter response (indication)—reproducible, quan-
ment
tifiablechangeproducedinthedosimeterbyionizingradiation.
ISO 14470 Food irradiation – Requirements for the
3.1.6.1 Discussion—The dosimeter response value
development, validation and routine control of the process
(indication), obtained from one or more measurements, is used
of irradiation using ionizing radiation for the treatment of
intheestimationofthedosimetricquantity.Theresponsevalue
food
(indication) may be obtained from such measurements as
ISO/IEC 17025 General requirements for the competence of
optical absorbance, intensity of EPR spectra, or electropoten-
testing and calibration laboratories
tial between solutions.
2.4 International Commission on Radiation Units and Mea-
3.1.7 dosimetry—measurement of a dosimetric quantity by
4
surements (ICRU) Reports:
the use of a dosimetry system.
ICRU Report 80 Dosimetry Systems for Use in Radiation
3.1.8 dosimetry system—interrelatedelementsusedformea-
Processing
suring a dosimetric quantity, including dosimeters, instruments
ICRU Report 85a Fundamental Quantities and Units for
and their associated reference standards, and procedures for
Ionizing Radiation
their use.
2.5 Joint Committee for Guides in Metrology (JCGM)
Reports:
3.1.8.1 Discussion—As discussed in ICRU-85a, dosimetric
JCGM 100:2008, GUM , 1995, with minor corrections,
quantities provide a physical measure to correlate with actual
Evaluation of measurement data – Guide to the Expres-
or potential effects.They are products of radiometric quantities
5
sion of Uncertainty in Measurement
and interaction coefficients. In calculations, the values of these
JCGM 200:2012, VIM , International vocabulary of metrol-
quantities and coefficients must be known, while measure-
6
ogy – basic and general concepts and associated terms
mentsmightnotrequirethisinformation.Dosimetricquantities
include air kerma, exposure and absorbed dose to a specified
3. Terminology
material.
3.1 Definitions: 3.1.8.2 Discussion—In radiation processing applications the
3.1.1 absorbed dose (D)—quotient of dε by dm, where dε is quantityofinterestisusuallyabsorbeddosetowater.Absorbed
¯ ¯
the mean energy imparted by ionizing radiation to matter of dose to silicon might be used in semiconductor irradiations.
mass dm, thus 3.1.9 influence quantity—quantity that, in a direct
measurement, does not affect the quantity that is actually
D 5 dε¯⁄dm
measured, but affects the relation between the indication and
ICRU 85a
the measurement result. VIM
3.1.1.1 Discussion—TheSIunitofabsorbeddoseisthegray
3.1.9.1 Discussion—In dosimetry for radiation processing,
(Gy),where1grayisequivalenttotheabsorptionof1jouleper
typical examples of influence quantities include radiation type
kilogram of the specified material (1 Gy = 1 J/kg).
and energy, irradiation temperature, dose rate and the time
3.1.2 calibration—operation that, under specified
intervalbetweenirradiationanddeterminationoftheindication
conditions, in a first step, establishes a relation between the
of the dosimeter.
quantity values with measurement uncertainties provided by
3.1.10 measurement management system—set of interre-
measurement standards and corresponding indications with
lated or interacting elements necessary to achieve metrological
associated measurement uncertainties and, in a second step,
confirmation and continual control of measurement processes.
uses this information to establish a relation for obtaining a
ISO 10012
measurement result from an indication. VIM
3.1.10.1 Discussion—See 7.6 for further details.
3.1.3 calibration curve—expression of the relation between
3.1.11 (measurement) uncertainty—non-negative parameter
indication and corresponding measured quantity value. VIM
characterizing characterizing the dispersion of the quantity
3.1.4 dosimeter—device that, when irradiated, exhibits a
values being attributed to a measurand, based on the informa-
quantifiable change that can be related to a dosimetric quantity
tion used. VIM
using appropriate measurement instrument(s) and procedures.
3.1.12 (metrological) traceability—property of a measure-
3.1.5 dosimeter characterization / dosimetry system
ment result whereby the result can be related to a reference
characterization—determination of performance
through a documented unbroken chain of calibrations, each
characteristics, such as dose range, reproducibility and the
contributing to the measurement uncertainty. VIM
4
3.1.13 primary standard dosimetry system —dosimetry sys-
Available from the International Commission on Radiation Units and
tem that is designated or widely acknowledged as having the
Measurements, 7910 Woodmont Ave, Suite 800, Bethesda, MD 20815, USA.
5 highest metrological qualities and whose value is accepted
Document produced by Working Group 1 of the Joint Committee for Guides in
Metrology (JCGM/WG 1). Available free of charge at the BIPM website (http:// without reference to other standards of the same quantity.
www.bipm.org).
3.1.14 radiation processing—intentionalirradiationofprod-
6
Document produced by Working Group 2 of the Joint Committee for Guides in
ucts or materials to preserve, modify or improve their charac-
Metrology (JCGM/WG 2). Available free of charge at the BIPM website (http://
teristics.
www.bipm.org).
3
© ISO/ASTM International 2020 – All rights reserved

---------------------- Page: 7 ----------------------
ISO/ASTM 52628:2020(E)
3.1.15 reference standard dosimetry system—dosimetry 5. Dosimetry system requirements
system, generally having the highest metrological quality
5.1 Dosimetrysystemrequirementsareanecessarypartofa
available at a given location or in a given organization, from
measurement management system.The following requirements
which measurements made there are derived.
shall be included as a minimum, but additional requirements
may be appropriate depending on the nature of the process.
3.1.16 reference standard radiation field—calibrated radia-
tion field, generally having the highest metrological quality Guidance on these requirements is given in Section 7.
5.1.1 Theselectionanduseofaspecificdosimetrysystemin
available at a given location or in a given organization, from
which measurements made there are derived. a given application shall be justified and documented. The
justification shall take into account at least the following:
3.1.17 routine dosimetry system—dosimetry system cali-
dose range
brated against a reference standard dosimetry system and used
radiation type and energy
for routine absorbed dose measurements, including dose map-
effect of influence quantities
ping and process monitoring.
level of uncertainty
3.1.18 transfer standard dosimetry system—dosimetry sys-
spatial resolution
tem used as an intermediary to calibrate other dosimetry
5.1.2 The dosimetry system shall be calibrated in accor-
systems.
dance with the requirements of ISO/ASTM Practice 51261.
5.1.3 The uncertainty associated with measurements made
3.1.19 type I dosimeter—dosimeter of high metrological
with the selected dosimetry system shall be established and
quality, the response of which is affected by individual influ-
documented. All dose measurements shall be accompanied by
ence quantities in a way that is well-defined and capable of
an estimate of uncertainty. See ISO/ASTM 51707, NPLReport
expression in terms of independent correction factors.
7 8
CIRM 29 , GUM and NIST Technical Note 1297 for guid-
3.1.19.1 Discussion—See Section 6 for examples and fur-
ance.
ther details.
5.1.4 Documentation shall be established and maintained to
3.1.20 type II dosimeter—dosimeter, the response of which
ensurecompliancewiththeminimumrequirementsspecifiedin
is affected by influence quantities in a complex way that cannot
the ASTM or ISO/ASTM standard relevant to the specific
practically be expressed in terms of independent correction
dosimetry system. The user’s quality system might be more
factors.
detailed than these minimum requirements.
3.1.20.1 Discussion—See Section 6 for examples and fur-
ther details. 6. Classification
6.1 Classification of dosimeters and dosimetry systems in
3.1.21 uncertainty budget—statement of a measurement
the ASTM E61 series of dosimetry standards is based on two
uncertainty, of the components of that measurement
distinct criteria: (1) the inherent metrological properties of the
uncertainty, and of their calculation and combination. VIM
dosimeter (see 3.1.19 and 3.1.20), and (2) the field of applica-
3.2 Definitions of other terms used in this standard that
tion of the dosimetry system (see 3.1.15 and 3.1.17). These
pertain to radiation measurement and dosimetry may be found
classifications are important in both the selection and calibra-
in ASTM Terminology E3083. Definitions in ASTM E3083 are
tion of dosimetry systems.
compatible with ICRU Report 85a; that document, therefore,
6.2 Classification of Dosimeters Based on Metrological
may be used as an alternative reference. Where appropriate,
Properties:
definitions used in this standard have been derived from, and
6.2.1 This classification of dosimeters is based on knowl-
are consistent with, general metrological definitions given in
edge of their inherent metrological properties. The method of
the VIM.
measurement may be important in the classification (see
below), but the classification does not include consideration of
4. Significance and use
the quality of the actual instrumentation used, or the quality of
4.1 Radiation processing of articles in both commercial and
preparation (manufacture) of the dosimeter. For example,
research applications may be carried out for a number of
acidic solutions of dichromate ions have certain inherent
purposes. These include, for example, sterilization of health
properties in terms of their response to radiation and the effect
care products, reduction of the microbial populations in foods
of irradiation temperature that means they are classified as type
and modification of polymers. The radiations used may be
I dosimeters. The actual performance of a given dosimetry
accelerated electrons, gamma-radiation from radionuclide
system based on dichromate dosimeters will depend, however,
sources such as cobalt-60, or X-radiation.
on the quality of preparation of the dosimetric solution and the
quality of the spectrophotometers used for optical absorbance
4.2 To demonstrate control of radiation processes that are
measurement.
dependent on the delivery of a known dose, the absorbed dose
must be measured using a dosimetry system, the calibration of
7
which, is traceable to appropriate national or international
Sharpe,P.,andMiller,A.,“GuidelinesfortheCalibrationofRoutineDosimetry
Systems for use in Radiations Processing,” NPLReport CIRM 29, Teddington, UK,
standards. The radiation-induced change in the dosimeter is
2009.
evaluated and related to absorbed dose through calibration.
8
Taylor, B. N., and Kuyatt, C. E., “Guidelines for Evaluating and Expressing the
Dose measurements required for particular processes are de-
Uncertainty of NIST Measurement Results,” NIST TN-1297, Gaithersburg, MD:
scribed in other standards referenced in this practice. NIST 1994.
© ISO/ASTM International 2020 – All rights reserved
4

---------------------- Page: 8 ----------------------
ISO/ASTM 52628:2020(E)
6.2.2 Knowledge of the inherent properties of a dosimeter is system with low uncertainty and with traceability to appropri-
important when selecting a dosimeter for a particular applica- ate national or international standards.
tion. For example, when selecting a dosimeter to be used to
6.3.1.2 Reference standard dosimetry systems may take the
transferdosebetweenradiationfieldsofdifferingtemperatures,
form of systems held at a given location or they may take the
it is essential to choose a dosimeter whose response can be
form of transfer standard dosimetry systems operated by a
correctedfortheeffectofirradiationtemperature,thatis,a type
national standards laboratory or by a laboratory accredited to
I dosimeter.
ISO/IEC 17025. In the case of transfer standard dosimetry
6.2.3 In order for a dosimeter to be classified as a type I
systems, dosimeters are sent to a facility for irradiation and
dosimeter, it must be possible to apply accurate, independent,
then returned to the issuing laboratory for measurement. The
corrections to its response to account for the effects of relevant
requirement to transport dosimeters without unduly increasing
influence quantities, such as temperature, dose rate, etc., or to
measurement uncertainty restricts the type of dosimeter that
demonstrate that the influence quantity is not relevant and will
can be used. Alanine/EPR, dichromate or ceric-cerous dosim-
not affect the dosimeter’s response. The magnitude of the
etry systems are commonly used in this way.
correction, the range of values of the influence quantity over
6.3.1.3 A reference standard dosimetry system comprises
which it is applicable and the range of doses over which it is
dosimeters and the associated measurement equipment and
applicable are determined as part of dosimeter characterization
quality system documentation necessary to ensure traceability
(see 7.3). In classifying a dosimeter as a type I dosimeter,it
to appropriate national and international standards. The dosim-
may be necessary to specify the method of measurement. For
eter used in a reference standard dosimetry system is generally
example, free radicals produced in irradiated alanine can, in
a type I dosimeter, although there may be exceptions (see, for
principle, be measured by a n
...