SIST EN ISO 15708-4:2025

SLOVENSKI STANDARD
01-oktober-2025
Neporušitvene preiskave - Sevalne metode za računalniško tomografijo - 4. del:
Usposobljenost (ISO 15708-4:2025)
Non-destructive testing - Radiation methods for computed tomography - Part 4:
Qualification (ISO 15708-4:2025)
Zerstörungsfreie Prüfung - Durchstrahlungsverfahren für Computertomographie - Teil 4:
Qualifizierung (ISO 15708-4:2025)
Essais non destructifs - Méthodes par rayonnements pour la tomographie informatisée -
Partie 4: Qualification (ISO 15708-4:2025)
Ta slovenski standard je istoveten z: EN ISO 15708-4:2025
ICS:
19.100 Neporušitveno preskušanje Non-destructive testing
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 15708-4
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2025
EUROPÄISCHE NORM
ICS 19.100 Supersedes EN ISO 15708-4:2019
English Version
Non-destructive testing - Radiation methods for computed
tomography - Part 4: Qualification (ISO 15708-4:2025)
Essais non destructifs - Méthodes par rayonnements Zerstörungsfreie Prüfung - Durchstrahlungsverfahren
pour la tomographie informatisée - Partie 4: für Computertomographie - Teil 4: Qualifizierung (ISO
Qualification (ISO 15708-4:2025) 15708-4:2025)
This European Standard was approved by CEN on 3 June 2025.

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, Türkiye 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
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 15708-4:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 15708-4:2025) has been prepared by Technical Committee ISO/TC 135 "Non-
destructive testing " in collaboration with 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 December 2025, and conflicting national standards
shall be withdrawn at the latest by December 2025.
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 15708-4:2019.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
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, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 15708-4:2025 has been approved by CEN as EN ISO 15708-4:2025 without any
modification.
International
Standard
ISO 15708-4
Second edition
Non-destructive testing —
2025-06
Radiation methods for computed
tomography —
Part 4:
Qualification
Essais non destructifs — Méthodes par rayonnements pour la
tomographie informatisée —
Partie 4: Qualification
Reference number
ISO 15708-4:2025(en) © ISO 2025

ISO 15708-4:2025(en)
© ISO 2025
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
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 15708-4:2025(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Qualification of the testing . 1
4.1 General .1
4.2 Qualification of defect testing .2
4.2.1 General .2
4.2.2 Objects and features .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 verification .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 . . .6
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 General .7
6.2 Acquisition parameters .8
6.3 Recommendations for creating reference objects .8
6.4 Density resolution measurement method .8
6.4.1 General .8
6.4.2 High energy reference object .9
6.4.3 Low energy reference object .9
6.4.4 Experimental measurements .9

iii
ISO 15708-4:2025(en)
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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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 Technical Committee ISO/TC 135, Non-destructive testing, Subcommittee SC
5, Radiographic testing, in collaboration with the European Committee for Standardization (CEN) Technical
Committee CEN/TC 138, Non-destructive testing, in accordance with the Agreement on technical cooperation
between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 15708-4:2017), which has been technically
revised.
The main changes are as follows:
— addition of ISO 15708-1 and ISO 15708-3 as normative references in Clause 2;
— correction of title in Figure 1;
— correction of density values d of each insert and CT grey values N in 6.4.4;
R i
— deletion of the bibliography;
— editorial changes.
A list of all parts in the ISO 15708 series can be found on the ISO website.
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
International Standard ISO 15708-4:2025(en)
Non-destructive testing — Radiation methods for computed
tomography —
Part 4:
Qualification
1 Scope
This document gives guidance on the qualification of the performance of a computed tomography (CT)
system with respect to various testing tasks.
This document is applicable only to industrial imaging (i.e. non-medical applications) and provides a
consistent set of definitions of CT performance parameters, including the relationship between these
performance parameters and CT system specifications.
This document is applicable to industrial computed tomography.
This document does not apply to other techniques 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 15708-1, Non-destructive testing — Radiation methods for computed tomography — Part 1: Vocabulary
ISO 15708-3:2025, Non-destructive testing — Radiation methods for computed tomography — Part 3: 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 terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
4 Qualification of the testing
4.1 General
CT is used in industry both for defect testing and analysis as well as dimensional testing and measurement.
Since CT does not provide a direct measurement of the desired quantities such as e.g. pore size or wall
thickness, these quantities shall 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 testing
task, the specification of the available test equipment and the analysis and evaluation methods used. If the
determination of such quantities is required, a special task-specific qualification procedure of the applied CT

ISO 15708-4:2025(en)
system shall be performed. The qualification parameters are specified in 4.2 and 4.3. This qualification shall
be carried out by trained personnel. The trained personnel shall be trained and qualified in CT or digital
industrial radiography or radioscopy.
4.2 Qualification of defect testing
4.2.1 General
As part of the test qualification, the suitability of the CT testing technique for measuring a quantity with
the required accuracy shall be verified. The steps described in clause 4 are necessary for successful
demonstration of the suitability of CT for this specific industrial application.
4.2.2 Objects and features
Typical quantities to be
...