Non-destructive testing - Radiation methods for computed tomography - Part 4: Qualification (ISO 15708-4:2017)

ISO 15708-4:2017 specifies guidelines for the qualification of the performance of a CT system with respect to various inspection tasks.
It is applicable to industrial imaging (i.e. non-medical applications) and gives a consistent set of CT performance parameter definitions, including how those performance parameters relate to CT system specifications.
ISO 15708-4:2017 deals with computed axial tomography and excludes other types of tomography such as translational tomography and tomosynthesis.

Zerstörungsfreie Prüfung - Durchstrahlungsverfahren für Computertomografie - Teil 4: Qualifizierung (ISO 15708-4:2017)

Dieses Dokument legt Leitlinien für die Qualifizierung des Leistungsverhaltens eines CT-Systems unter Beachtung verschiedener Prüfaufgaben fest.
Es gilt für die industrielle Bildgebung (d. h. nicht medizinische Anwendungen) und bietet einen einheitlichen Satz von Festlegungen zu CT-Leistungsparametern, einschließlich der Art des Zusammenhangs dieser Leistungsparameter mit den Spezifikationen des CT-Systems.
Dieses Dokument befasst sich mit der axialen Computertomographie und schließt weitere Arten der Tomographie, wie z. B. Translationstomographie und Tomosynthese, aus.

Essais non destructifs - Méthodes par rayonnements pour la tomographie informatisée - Part 4: Qualification (ISO 15708-4:2017)

Le présent document décrit des lignes directrices pour qualifier la performance d'un système TI par rapport à différentes tâches d'examen.
Il est applicable à l'imagerie industrielle (c'est-à-dire aux applications non médicales) et donne un ensemble cohérent de définitions des paramètres de performance de la TI, y compris la façon dont ces paramètres sont reliés aux spécifications du système TI.
Le présent document traite de la tomographie axiale informatisée et exclut les autres types de tomographie, tels que la tomographie par translation et la tomosynthèse.

Neporušitvene preiskave - Sevalne metode za računalniško tomografijo - 4. del: Usposobljenost (ISO 15708-4:2017)

Standard ISO 15708-4:2017 določa smernice za oceno usposobljenosti delovanja sistema računalniške tomografije glede na različne kontrolne naloge.
Uporablja se za slikanje v industriji (npr. v nemedicinske namene) in podaja dosleden sklop definicij podatkov delovanja računalniške tomografije, vključno s tem, kako so podatki delovanja povezani s specifikacijami sistema računalniške tomografije.
Standard ISO 15708-4:2017 obravnava računalniško aksialno tomografijo in izključuje druge vrste tomografij, kot so translacijska tomografija in tomosinteza.

General Information

Status
Published
Public Enquiry End Date
30-Dec-2018
Publication Date
05-Jun-2019
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
04-Apr-2019
Due Date
09-Jun-2019
Completion Date
06-Jun-2019

Relations

Buy Standard

Standard
EN ISO 15708-4:2019 - BARVE
English language
18 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day
Draft
prEN ISO 15708-4:2018 - BARVE
English language
15 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 15708-4:2019
01-julij-2019
Nadomešča:
SIST EN 16016-4:2012
Neporušitvene preiskave - Sevalne metode za računalniško tomografijo - 4. del:
Usposobljenost (ISO 15708-4:2017)
Non-destructive testing - Radiation methods for computed tomography - Part 4:
Qualification (ISO 15708-4:2017)
Zerstörungsfreie Prüfung - Durchstrahlungsverfahren für Computertomografie - Teil 4:
Qualifizierung (ISO 15708-4:2017)
Essais non destructifs - Méthodes par rayonnements pour la tomographie informatisée -
Part 4: Qualification (ISO 15708-4:2017)
Ta slovenski standard je istoveten z: EN ISO 15708-4:2019
ICS:
19.100 Neporušitveno preskušanje Non-destructive testing
SIST EN ISO 15708-4:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST EN ISO 15708-4:2019

---------------------- Page: 2 ----------------------

SIST EN ISO 15708-4:2019


EN ISO 15708-4
EUROPEAN STANDARD

NORME EUROPÉENNE

March 2019
EUROPÄISCHE NORM
ICS 19.100 Supersedes EN 16016-4:2011
English Version

Non-destructive testing - Radiation methods for computed
tomography - Part 4: Qualification (ISO 15708-4:2017)
Essais non destructifs - Méthodes par rayonnements Zerstörungsfreie Prüfung - Durchstrahlungsverfahren
pour la tomographie informatisée - Part 4: für Computertomografie - Teil 4: Qualifizierung (ISO
Qualification (ISO 15708-4:2017) 15708-4:2017)
This European Standard was approved by CEN on 11 February 2019.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, 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
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 15708-4:2019 E
worldwide for CEN national Members.

---------------------- Page: 3 ----------------------

SIST EN ISO 15708-4:2019
EN ISO 15708-4:2019 (E)
Contents Page
European foreword . 3

2

---------------------- Page: 4 ----------------------

SIST EN ISO 15708-4:2019
EN ISO 15708-4:2019 (E)
European foreword
The text of ISO 15708-4:2017 has been prepared by Technical Committee 135 "Non-destructive testing”
of the International Organization for Standardization (ISO) and has been taken over as EN ISO 15708-
4:2019 by Technical Committee CEN/TC 138 “Non-destructive testing” 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 September 2019, and conflicting national standards
shall be withdrawn at the latest by September 2019.
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 16016-4:2011.
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, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 15708-4:2017 has been approved by CEN as EN ISO 15708-4:2019 without any
modification.

3

---------------------- Page: 5 ----------------------

SIST EN ISO 15708-4:2019

---------------------- Page: 6 ----------------------

SIST EN ISO 15708-4:2019
INTERNATIONAL ISO
STANDARD 15708-4
First edition
    2017-02
Non-destructive testing — Radiation
methods for computed tomography —
Part 4:
Qualification
Essais non destructifs — Méthodes par rayonnements pour la
tomographie informatisée —
Partie 4: Qualification
Reference number
ISO 15708-4:2017(E)
©
ISO 2017

---------------------- Page: 7 ----------------------

SIST EN ISO 15708-4:2019
ISO 15708-4:2017(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2017, Published in Switzerland
All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2017 – All rights reserved

---------------------- Page: 8 ----------------------

SIST EN ISO 15708-4:2019
ISO 15708-4:2017(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Qualification of the inspection . 1
4.1 General . 1
4.2 Qualification of defect testing . 2
4.2.1 General. 2
4.2.2 Quality feature . 2
4.2.3 Feature detectability/test system/system parameterisation . 2
4.2.4 Verification of suitability . 3
4.2.5 Consistency check . 3
4.2.6 Documentation . 4
4.3 Qualification of dimensional testing . 4
4.3.1 General. 4
4.3.2 Test and measurement task . 4
4.3.3 Dimensional testing/test system/system parameterisation . 4
4.3.4 Degree of accuracy . 5
4.3.5 Consistency check . 5
4.3.6 Documentation . 5
5 Qualification of the CT system . 6
5.1 General . 6
5.2 Integral overall system test . 6
5.3 Checking the system components . 6
5.3.1 General. 6
5.3.2 Manipulation system . 6
5.3.3 Image scale . 6
5.3.4 Beam axis perpendicularity . 6
5.3.5 Tube focal spot . 7
5.3.6 Tube stability . 7
5.3.7 Detector . 7
5.3.8 Reconstruction . 7
5.3.9 Visualization . 7
5.4 Documentation . 7
6 Example of CT system resolution evaluation methods . 7
6.1 Pre-amble . 7
6.2 Acquisition parameters . 8
6.3 Recommendations for creating reference objects . 8
6.4 Density resolution measurement method. 9
6.4.1 General. 9
6.4.2 High energy reference object . 9
6.4.3 Low energy reference object . 9
6.4.4 Experimental measurements . 9
Bibliography .11
© ISO 2017 – All rights reserved iii

---------------------- Page: 9 ----------------------

SIST EN ISO 15708-4:2019
ISO 15708-4:2017(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 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 the European Committee for Standardization (CEN) (as EN 16016-4)
and was adopted, under a special “fast-track procedure”, by Technical Committee ISO/TC 135, Non-
destructive testing, Subcommittee SC 5, Radiographic testing, in parallel with its approval by the national
bodies of ISO.
It takes into consideration developments in computed tomography (CT) and computational power over
the preceding decade.
A list of all parts in the ISO 15708 series can be found on the ISO website.
iv © ISO 2017 – All rights reserved

---------------------- Page: 10 ----------------------

SIST EN ISO 15708-4:2019
INTERNATIONAL STANDARD ISO 15708-4:2017(E)
Non-destructive testing — Radiation methods for
computed tomography —
Part 4:
Qualification
1 Scope
This document specifies guidelines for the qualification of the performance of a CT system with respect
to various inspection tasks.
It is applicable to industrial imaging (i.e. non-medical applications) and gives a consistent set of CT
performance parameter definitions, including how those performance parameters relate to CT system
specifications.
This document deals with computed axial tomography and excludes other types of tomography such as
translational tomography and tomosynthesis.
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.
ISO 15708-2, Non-destructive testing — Radiation methods for computed tomography — Part 2: Operation
and interpretation
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 15708-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
4 Qualification of the inspection
4.1 General
CT is used in industry both for defect testing and dimensional testing and measurement. Since CT does
not directly provide measurement of desired quantities such as, for example, pore size or wall thickness,
these quantities must be derived from the X-ray linear attenuation data represented by the CT grey
values. The detectability of features and the degree of accuracy required depend on the inspection task,
the specification of the available test equipment and the analysis and evaluation methods used. When
determination of such quantities is required, a special task-specific qualification test of the CT system
is required. The qualification measures are described in 4.2 and 4.3. The qualification should be carried
out by trained personnel. The trained personnel shall be able to prove they have undergone training
and qualification in digital industrial radiography or radioscopy.
© ISO 2017 – All rights reserved 1

---------------------- Page: 11 ----------------------

SIST EN ISO 15708-4:2019
ISO 15708-4:2017(E)

4.2 Qualification of defect testing
4.2.1 General
Under test qualification, the suitability of the CT inspection technique for measuring a quantity to
the required precision should be verified. The following steps described are typical of those for the
successful verification of the suitability of CT for industrial applications.
4.2.2 Quality feature
Typical quantities to be measured are the sizes of pores, cavities, cracks, inclusions, contaminants as
well as studies of the material distribution and the assembly and installation position of components.
Because the test sample and the type, position and size of the features to be detected determine the
properties of a CT system to be used, information such as the following should be known:
a) test object:
1) dimensions;
2) weight;
3) materials;
4) path length to be X-rayed in the material;
b) test feature:
1) type;
2) position;
3) size;
4) distribution, frequency;
c)
...

SLOVENSKI STANDARD
oSIST prEN ISO 15708-4:2018
01-december-2018
1HSRUXãLWYHQRSUHVNXãDQMH6HYDOQHPHWRGH]DUDþXQDOQLãNRWRPRJUDILMRGHO
8VSRVREOMHQRVW ,62
Non-destructive testing - Radiation methods for computed tomography - Part 4:
Qualification (ISO 15708-4:2017)
Zerstörungsfreie Prüfung - Durchstrahlungsverfahren für Computertomografie - Teil 4:
Qualifizierung (ISO 15708-4:2017)
Essais non destructifs - Méthodes par rayonnements pour la tomographie informatisée -
Part 4: Qualification (ISO 15708-4:2017)
Ta slovenski standard je istoveten z: prEN ISO 15708-4
ICS:
19.100 Neporušitveno preskušanje Non-destructive testing
oSIST prEN ISO 15708-4:2018 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN ISO 15708-4:2018

---------------------- Page: 2 ----------------------
oSIST prEN ISO 15708-4:2018
INTERNATIONAL ISO
STANDARD 15708-4
First edition
    2017-02
Non-destructive testing — Radiation
methods for computed tomography —
Part 4:
Qualification
Essais non destructifs — Méthodes par rayonnements pour la
tomographie informatisée —
Partie 4: Qualification
Reference number
ISO 15708-4:2017(E)
©
ISO 2017

---------------------- Page: 3 ----------------------
oSIST prEN ISO 15708-4:2018
ISO 15708-4:2017(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2017, Published in Switzerland
All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2017 – All rights reserved

---------------------- Page: 4 ----------------------
oSIST prEN ISO 15708-4:2018
ISO 15708-4:2017(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Qualification of the inspection . 1
4.1 General . 1
4.2 Qualification of defect testing . 2
4.2.1 General. 2
4.2.2 Quality feature . 2
4.2.3 Feature detectability/test system/system parameterisation . 2
4.2.4 Verification of suitability . 3
4.2.5 Consistency check . 3
4.2.6 Documentation . 4
4.3 Qualification of dimensional testing . 4
4.3.1 General. 4
4.3.2 Test and measurement task . 4
4.3.3 Dimensional testing/test system/system parameterisation . 4
4.3.4 Degree of accuracy . 5
4.3.5 Consistency check . 5
4.3.6 Documentation . 5
5 Qualification of the CT system . 6
5.1 General . 6
5.2 Integral overall system test . 6
5.3 Checking the system components . 6
5.3.1 General. 6
5.3.2 Manipulation system . 6
5.3.3 Image scale . 6
5.3.4 Beam axis perpendicularity . 6
5.3.5 Tube focal spot . 7
5.3.6 Tube stability . 7
5.3.7 Detector . 7
5.3.8 Reconstruction . 7
5.3.9 Visualization . 7
5.4 Documentation . 7
6 Example of CT system resolution evaluation methods . 7
6.1 Pre-amble . 7
6.2 Acquisition parameters . 8
6.3 Recommendations for creating reference objects . 8
6.4 Density resolution measurement method. 9
6.4.1 General. 9
6.4.2 High energy reference object . 9
6.4.3 Low energy reference object . 9
6.4.4 Experimental measurements . 9
Bibliography .11
© ISO 2017 – All rights reserved iii

---------------------- Page: 5 ----------------------
oSIST prEN ISO 15708-4:2018
ISO 15708-4:2017(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 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 the European Committee for Standardization (CEN) (as EN 16016-4)
and was adopted, under a special “fast-track procedure”, by Technical Committee ISO/TC 135, Non-
destructive testing, Subcommittee SC 5, Radiographic testing, in parallel with its approval by the national
bodies of ISO.
It takes into consideration developments in computed tomography (CT) and computational power over
the preceding decade.
A list of all parts in the ISO 15708 series can be found on the ISO website.
iv © ISO 2017 – All rights reserved

---------------------- Page: 6 ----------------------
oSIST prEN ISO 15708-4:2018
INTERNATIONAL STANDARD ISO 15708-4:2017(E)
Non-destructive testing — Radiation methods for
computed tomography —
Part 4:
Qualification
1 Scope
This document specifies guidelines for the qualification of the performance of a CT system with respect
to various inspection tasks.
It is applicable to industrial imaging (i.e. non-medical applications) and gives a consistent set of CT
performance parameter definitions, including how those performance parameters relate to CT system
specifications.
This document deals with computed axial tomography and excludes other types of tomography such as
translational tomography and tomosynthesis.
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.
ISO 15708-2, Non-destructive testing — Radiation methods for computed tomography — Part 2: Operation
and interpretation
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 15708-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
4 Qualification of the inspection
4.1 General
CT is used in industry both for defect testing and dimensional testing and measurement. Since CT does
not directly provide measurement of desired quantities such as, for example, pore size or wall thickness,
these quantities must be derived from the X-ray linear attenuation data represented by the CT grey
values. The detectability of features and the degree of accuracy required depend on the inspection task,
the specification of the available test equipment and the analysis and evaluation methods used. When
determination of such quantities is required, a special task-specific qualification test of the CT system
is required. The qualification measures are described in 4.2 and 4.3. The qualification should be carried
out by trained personnel. The trained personnel shall be able to prove they have undergone training
and qualification in digital industrial radiography or radioscopy.
© ISO 2017 – All rights reserved 1

---------------------- Page: 7 ----------------------
oSIST prEN ISO 15708-4:2018
ISO 15708-4:2017(E)

4.2 Qualification of defect testing
4.2.1 General
Under test qualification, the suitability of the CT inspection technique for measuring a quantity to
the required precision should be verified. The following steps described are typical of those for the
successful verification of the suitability of CT for industrial applications.
4.2.2 Quality feature
Typical quantities to be measured are the sizes of pores, cavities, cracks, inclusions, contaminants as
well as studies of the material distribution and the assembly and installation position of components.
Because the test sample and the type, position and size of the features to be detected determine the
properties of a CT system to be used, information such as the following should be known:
a) test object:
1) dimensions;
2) weight;
3) materials;
4) path length to be X-rayed in the material;
b) test feature:
1) type;
2) position;
3) size;
4) distribution, frequency;
c) feature detectability:
1) limiting defect;
2) limiting feature.
Since the feature detectability strongly influences the specification and therefore the cost of a CT
system, special attention must be taken when defining the sensitivity of the tests required. If, due
to missing information, no limiting values for features are defined, it is recommended that the best
possible sensitivity is used for the specific method and CT system and the attained feature detectability
is verified using, for example, destructive tests.
4.2.3 Feature detectability/test system/system parameterisation
The usability of the CT system and the selection of system parameters are determined by the
requirements for feature detectability. Typical variables are:
a) spatial resolution:
1) overall spatial resolution of the CT image;
2) scan geometry;
3) detector spatial resolution;
2 © ISO 2017 – All rights reserved

---------------------- Page: 8 ----------------------
oSIST prEN ISO 15708-4:2018
ISO 15708-4:2017(E)

4) focal spot size of radiation source;
b) contrast resolution:
1) overall contrast resolution of the CT image;
2) detector settings;
3) tube voltage;
4) tube current;
c) reconstruction/visualization:
1) number of projections;
2) CT grey value dynamic range of the reconstruction or visualization;
3) CT image size in X, Y and Z axes.
CT system set-up and image quality parameters are described in ISO 15708-2:2016, 4.1 and 5.1.
4.2.4 Verification of suitability
4.2.4.1 General
A reliable statement on the defect detection sensitivity and the defect detectability of the CT system
used in a test shall be made by stating the degree of accuracy of the test required (tolerance, degree of
fluctuation). Several alternative procedures are described in the following.
4.2.4.2 Reference samples with natural defects
If a reference sample with a known defect is available, inspection of this sample is carried out and the
detectability is stated after the test has been done.
If a reference sample with unquantified defects is available, ins
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.