EN IEC 61267:2026

SLOVENSKI STANDARD
01-april-2026
Nadomešča:
SIST EN 61267:2006
Medicinska diagnostična rentgenska oprema - Sevalni pogoji pri določanju
karakteristik (IEC 61267:2025)
Medical diagnostic X-ray equipment - Radiation conditions for use in the determination of
characteristics (IEC 61267:2025)
Medizinische diagnostische Röntgeneinrichtung - Bestrahlungsbedingungen zur
Bestimmung von Kenngrößen (IEC 61267:2025)
Equipement de diagnostic médical à rayonnement x - Conditions de rayonnement pour
utilisation dans la détermination des caractéristiques (IEC 61267:2025)
Ta slovenski standard je istoveten z: EN IEC 61267:2026
ICS:
11.040.50 Radiografska oprema Radiographic equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 61267

NORME EUROPÉENNE
EUROPÄISCHE NORM February 2026
ICS 11.040.50 Supersedes EN 61267:2006
English Version
Medical diagnostic X-ray equipment - Radiation conditions for
use in the determination of characteristics
(IEC 61267:2025)
Equipement de diagnostic médical à rayonnement X - Medizinische diagnostische Röntgeneinrichtung -
Conditions de rayonnement pour utilisation dans la Bestrahlungsbedingungen zur Bestimmung von
détermination des caractéristiques Kenngrößen
(IEC 61267:2025) (IEC 61267:2025)
This European Standard was approved by CENELEC on 2026-01-13. CENELEC 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 CENELEC 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 CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 61267:2026 E
European foreword
The text of document 62C/958/FDIS, future edition 3 of IEC 61267, prepared by SC 62C "Equipment
for radiotherapy, nuclear medicine and radiation dosimetry" of IEC/TC 62 "Medical equipment,
software, and systems" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC
as EN IEC 61267:2026.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2027-02-28
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2029-02-28
document have to be withdrawn
This document supersedes EN 61267:2006 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 61267:2025 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standard indicated:
IEC 60731:2011 NOTE Approved as EN 60731:2012 (not modified)
IEC 61676:2023 NOTE Approved as EN IEC 61676:2023 (not modified)
IEC 61267:2005 NOTE Approved as EN 61267:2006 (not modified)
IEC 62220-1-1 NOTE Approved as EN 62220-1-1
IEC 62220-1-3 NOTE Approved as EN 62220-1-3
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 61674 - Medical electrical equipment - Dosimeters EN IEC 61674 -
with ionization chambers and/or
semiconductor detectors as used in X-ray
diagnostic imaging
IEC 61676 - Medical electrical equipment - Dosimetric EN IEC 61676 -
instruments used for non-invasive
measurement of X-ray tube voltage in
diagnostic radiology
IEC 61267 ®
Edition 3.0 2025-12
INTERNATIONAL
STANDARD
Medical diagnostic X-ray equipment - Radiation conditions for use in the
determination of characteristics

ICS 11.040.50  ISBN 978-2-8327-0873-6

IEC 61267:2025-12(en)
IEC 61267:2025 © IEC 2025
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
3.1 Terms defined in this document . 7
3.2 Terms defined in other standards . 8
4 Common aspects . 16
4.1 X-ray radiation conditions . 16
4.2 Test instrumentation . 16
4.2.1 Maximum inherent filtration . 16
4.2.2 Anode material . 16
4.2.3 Percentage ripple of the X-ray tube voltage . 16
4.2.4 X-ray tube voltage adjustment . 16
4.2.5 X-ray tube voltage measuring device. 17
4.2.6 Radiation detector . 17
4.2.7 Measuring arrangements . 17
5 RQR X-ray radiation conditions . 17
5.1 Object . 17
5.2 Characterization . 17
5.3 Description . 17
5.4 Additional filtration . 18
5.5 Test equipment. 18
5.5.1 Auxiliary filter . 18
5.5.2 Attenuation layers . 18
5.5.3 Diaphragm . 19
5.5.4 Radiation detector . 19
5.5.5 X-ray tube voltage measuring device. 19
5.6 Generation and verification . 19
5.6.1 Geometry . 19
5.6.2 RQR X-ray radiation conditions . 19
5.6.3 Series of RQR X-ray radiation conditions . 19
6 RQA X-ray radiation conditions . 20
6.1 Object . 20
6.2 Characterization . 20
6.3 Description . 20
6.4 Added filter . 21
6.5 Generation and verification . 21
6.5.1 RQA X-ray radiation conditions. 21
6.5.2 Alternative method . 21
7 RQC X-ray radiation conditions . 22
7.1 Object . 22
7.2 Characterization . 22
7.3 Description . 22

IEC 61267:2025 © IEC 2025
7.4 Added filter . 22
7.5 Generation and verification . 23
8 RQT X-ray radiation conditions . 23
8.1 Object . 23
8.2 Characterization . 23
8.3 Description . 23
8.4 Added filter . 24
8.5 Generation and verification . 24
8.5.1 RQT X-ray radiation conditions . 24
8.5.2 Alternative method . 24
9 RQN X-ray radiation conditions . 24
9.1 Object . 24
9.2 Characterization . 24
9.3 Description . 25
9.4 Phantom . 25
9.5 Diaphragms . 25
9.6 Generation . 25
10 RQB X-ray radiation conditions . 26
10.1 Object . 26
10.2 Characterization . 26
10.3 Description . 26
10.4 Phantom . 26
10.5 Diaphragms . 27
10.6 Generation . 27
11 RQR-M X-ray radiation conditions . 27
11.1 Object . 27
11.2 Characterization . 27
11.3 Description . 27
11.4 Generation and verification . 28
12 RQA-M X-ray radiation conditions. 28
12.1 Object . 28
12.2 Characterization . 28
12.3 Description . 28
12.4 Generation . 29
13 RQN-M X-ray radiation conditions . 29
13.1 Object . 29
13.2 Characterization . 29
13.3 Description . 29
13.4 Phantom . 30
13.5 Diaphragms . 30
13.6 Generation . 30
14 RQB-M X-ray radiation conditions. 30
14.1 Object . 30
14.2 Characterization . 31
14.3 Description . 31
14.4 Phantom . 31
14.5 Diaphragm . 32
14.6 Generation . 32
IEC 61267:2025 © IEC 2025
Annex A (normative) Measuring arrangements . 33
Annex B (informative) Determination of the amount of additional filtration . 39
Annex C (informative) Tabulated values for the squared signal-to-noise ratio per air
kerma (𝑆𝑆𝑆𝑆𝑆𝑆in2) . 40
Annex D (normative) Additional X-ray radiation conditions as used in mammography
and determination of the corresponding nominal aluminium half-value layers . 41
D.1 Object . 41
D.2 Characterization . 41
D.3 Description . 41
D.4 Generation and verification . 41
Annex E (informative) Overview of X-ray radiation conditions . 43
Bibliography . 44

Figure A.1 – Measuring arrangement for achieving RQR 2 to RQR 10 X-ray radiation
conditions . 33
Figure A.2 – Measuring arrangement for achieving RQA 2 to RQA 10 X-ray radiation
conditions . 34
Figure A.3 – Measuring arrangement for achieving RQN 2 to RQN 10 X-ray radiation
conditions . 35
Figure A.4 – Measuring arrangement for achieving RQB 2 to RQB 10 X-ray radiation
conditions . 36
Figure A.5 – Measuring arrangement for achieving RQN-M X-ray radiation conditions . 37
Figure A.6 – Measuring arrangement for achieving RQB-M X-ray radiation conditions . 38
Figure B.1 – Determination of additional filtration required for adjusting the total
filtration to the prescribed value (see 5.4). . 39

Table 1 – Parameters for RQR 2 to RQR 10 X-ray radiation conditions . 18
Table 2 – Parameters for RQA 2 to RQA 10 X-ray radiation conditions . 21
Table 3 – Parameters for RQC 3, RQC 5 and RQC 8 X-ray radiation conditions . 22
Table 4 – Parameters for RQT 8, RQT 9 and RQT 10 X-ray radiation conditions . 23
Table 5 – Parameters for RQR-M 1 to RQR-M 4 X-ray radiation conditions . 28
Table 6 – Parameters for RQA-M 1 to RQA-M 4 X-ray radiation conditions . 29
Table 7 – Parameters for RQN-M 1 to RQN-M 4 X-ray radiation conditions . 30
Table 8 – Parameters for RQB-M 1 to RQB-M 4 X-ray radiation conditions . 31
Table C.1 – 𝑆𝑆𝑆𝑆𝑆𝑆in2 values for the RQA X-ray radiation conditions . 40

IEC 61267:2025 © IEC 2025
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Medical diagnostic X-ray equipment - Radiation conditions for use in the
determination of characteristics

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for
standardization comprising all national electrotechnical committees (IEC National Committees).
The object of IEC is to promote international co-operation on all questions concerning
standardization in the electrical and electronic fields. To this end and in addition to other
activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
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Publication(s)”). Their preparation is entrusted to technical committees; any IEC National
Committee interested in the subject dealt with may participate in this preparatory work.
International, governmental and non-governmental organizations liaising with the IEC also
participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two
organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as
possible, an international consensus of opinion on the relevant subjects since each technical
committee has representation from all interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted
by IEC National Committees in that sense. While all reasonable efforts are made to ensure that
the technical content of IEC Publications is accurate, IEC cannot be held responsible for the
way in which they are used or for any misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC
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publications. Any divergence between any IEC Publication and the corresponding national or
regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies
provide conformity assessment services and, in some areas, access to IEC marks of conformity.
IEC is not responsible for any services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including
individual experts and members of its technical committees and IEC National Committees for
any personal injury, property damage or other damage of any nature whatsoever, whether direct
or indirect, or for costs (including legal fees) and expenses arising out of the publication, use
of, or reliance upon, this IEC Publication or any other IEC Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced
publications is indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve
the use of (a) patent(s). IEC 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,
IEC had not eceived 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 https://patents.iec.ch. IEC shall not be
held responsible for identifying any or all such patent rights.
IEC 61267:2025 © IEC 2025
IEC 61267 has been prepared by subcommittee 62C: Equipment for radiotherapy, nuclear
medicine and radiation dosimetry, of IEC technical committee 62: Medical equipment, software,
and systems. It is an International Standard.
This third edition cancels and replaces the second edition published 2005. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) removing former Annex C "Measurement of the practical peak voltage";
b) inserting informative Annex C "Tabulated values for the squared signal-to-noise ratio per air
kerma (𝑆𝑆𝑆𝑆𝑆𝑆 )" and normative Annex D "Additional X-ray radiation conditions as used in
in
mammography and determination of the corresponding nominal aluminium half-value
layers";
c) revision of X-ray radiation conditions;
d) new method for verification of X-ray radiation conditions;
e) change of term definitions.
The text of this International Standard is based on the following documents:
Draft Report on voting
62C/958/FDIS 62C/965/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at ww.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
IEC 61267:2025 © IEC 2025
INTRODUCTION
To establish characteristics, aspects or properties of associated equipment or to have available
radiation beams for physical and medical investigations, sets of well-defined X-ray radiation
conditions can offer an important tool in many situations.
From a regulation and standardization point of view, there is a need
– to have available well-defined X-ray radiation conditions that can be used internationally to
specify standards of operation of X-ray equipment,
– to provide a basis for the harmonization of existing national standards,
– to provide uniform sets of X-ray radiation conditions (a dictionary of X-ray radiation
conditions) to describe and judge the performance of X-ray equipment for the benefit of
manufacturers, users, patients and health protection authorities, and
– to solve communication problems between manufacturers, users and regulatory authorities,
stemming from a lack of internationally accepted definitions and test methods.
From an application point of view, commonly accepted sets of X-ray radiation conditions would
in general find use in
– quality control tests by manufacturers,
– installation and acceptance tests,
– calibration of test instrumentation,
– type approval tests (where required),
– inspection and tests by regulatory authorities and testing institutes,
– physical and medical studies in physical laboratories and medical facilities, and
– determination of characteristics of associated equipment.
Standardized X-ray radiation conditions can benefit a range of potential users, such as
– manufacturers of X-ray equipment,
– manufacturers of X-ray test instrumentation,
– research laboratories,
– testing institutes,
– government regulatory authorities,
– service organizations, and
– standardization organizations.
The X-ray radiation conditions defined in this document are intended to represent the range of
typical X-ray radiation beams encountered in medical diagnostic X-ray equipment. This includes
X-ray radiation beams passing through the filtration of an X-ray source assembly whereby the
radiation field includes only an insignificant amount of scattered radiation. It also includes the
more general case, where scattered radiation emerges from an exit surface of a patient or a
phantom. An overview of the X-ray radiation conditions defined in this document and of possible
applications can be found in Annex E.
Potential applications include studies for devices used in specific imaging modalities such as
mammography. However, the clauses of this document are not intended to represent specific
imaging modalities in general. For example, the X-ray radiation conditions described in Clause
5 can be useful for examinations of equipment found in dental radiography but also for
examinations of equipment related to chest radiography. In addition, some X-ray radiation
conditions can only partially cover the range of equipment for a particular imaging task.
Therefore, imaging modalities are not explicitly included or excluded from the scope of this
document.
IEC 61267:2025 © IEC 2025
1 Scope
This document applies to test procedures which, for the determination of characteristics of
systems or components of medical diagnostic X-ray equipment, require well-defined X-ray
radiation conditions.
This document deals with methods for generating X-ray radiation conditions which can be used
under test conditions typically found in test laboratories or in manufacturing facilities for the
determination of characteristics of medical diagnostic X-ray equipment.
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 61674, Medical electrical equipment - Dosimeters with ionization chambers and/or semi-
conductor detectors as used in X-ray diagnostic imaging
IEC 61676, Medical electrical equipment - Dosimetric instruments used for non-invasive
measurement of X-ray tube voltage in diagnostic radiology
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61674, IEC 61676
and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
3.1 Terms defined in this document
3.1.1
application distance
distance from the effective focal spot to the application plane
3.1.2
application plane
plane perpendicular to the central beam axis, where the X-ray radiation condition is defined
3.1.3
central beam axis
line from the effective focal spot through the centre of the diaphragm
3.1.4
exit surface
plane or curved surface through which the radiation beam emerges from an
irradiated object
3.1.5
homogeneity coefficient
ratio of first to second half-value layer
IEC 61267:2025 © IEC 2025
Note 1 to entry: The first HVL gives the thickness of a specified material which reduces the air kerma rate to half
the value without this material; the second HVL gives the additional thickness to reduce the air kerma rate to a
quarter.
3.1.6
X-ray radiation condition
selection of the following parameters to achieve specific X-ray beam characteristics:
– material of the emitting target;
– X-ray tube voltage;
– specific total filtration consisting of that of
• the X-ray tube assembly, and
• additional filtration;
– first half-value layer;
– homogeneity coefficient;
– application distance;
– properties of diaphragms;
– properties of a phantom used
Note 1 to entry: In the scope of this document the additional filtration is a result of added filters, phantoms and a
monitor chamber.
3.1.7
X-ray tube voltage
potential difference applied to an X-ray tube between the anode and the cathode
Note 1 to entry: The X-ray tube voltage can vary as a function of time. The practical peak voltage is a weighted
value of the X-ray tube voltage over a time period.
Note 2 to entry: The unit of this quantity is the volt (V).
3.1.8
reference direction
specified direction to which characteristics such as target angle, radiation field and
specifications with respect to the imaging quality of the radiation source are referenced
3.2 Terms defined in other standards
3.2.1
reference point
point of a radiation detector which, during the calibration of the detector, is brought to
coincidence with the point at which the conventional true value is specified
[SOURCE: IEC 60731:2011, 3.16, modified – The words "of the chamber" have been removed
from the preferred term; "an ionization chamber" has been replaced with a "radiation detector"
in the definition.]
3.2.2
practical peak voltage
^
𝑈𝑈
𝑈𝑈
max
𝑈𝑈
( ) ( )
∫ 𝑝𝑝𝑈𝑈 ×𝑤𝑤𝑈𝑈 ×𝑈𝑈𝑈𝑈𝑈𝑈 max
^
𝑈𝑈
min
𝑈𝑈 = with� 𝑝𝑝(𝑈𝑈)𝑈𝑈𝑈𝑈 = 1 (1)
𝑈𝑈
max
𝑝𝑝(𝑈𝑈) ×𝑤𝑤(𝑈𝑈)𝑈𝑈𝑈𝑈 𝑈𝑈
∫
min
𝑈𝑈
min
IEC 61267:2025 © IEC 2025
where
p(U) is the distribution function for the voltage U;
w(U) is a weighting function;
U is the highest voltage in the interval;
max
U is the lowest voltage in the interval
min
Note 1 to entry: The unit of the quantity practical peak voltage is the volt (V).
[SOURCE: IEC 61676:2023, 3.16, modified - The second note to entry has been deleted.]
3.2.3
acceptance test
test carried out after new equipment has been installed, or major modifications have been made
to existing equipment, in order to verify compliance with contractual specifications
[SOURCE: IEC TR 60788:2004, rm-70-01]
3.2.4
accessory
additional component for use with an equipment in order:
– to perform its intended use;
– to adapt the equipment to some special use;
– to facilitate the use of the equipment;
– to enhance the performance of the equipment;
– to enable the functions of the equipment to be integrated with those of other equipment
[SOURCE: IEC TR 60788:2004, rm-83-06]
3.2.5
added filter
removable or irremovable filter positioned in the radiation beam to provide part or all of the
additional filtration
[SOURCE: IEC TR 60788:2004, rm-35-02]
3.2.6
additional filtration
quality equivalent filtration due to added filters and other removable materials in the radiation
beam which are between the radiation source and the patient or a specified plane
[SOURCE: IEC TR 60788:2004, rm-13-47]
3.2.7
air kerma
K
d𝐸𝐸
tr
(2)
𝐾𝐾 =
d𝑚𝑚
IEC 61267:2025 © IEC 2025
where
dE is the sum of the initial kinetic energies of all the charged particles in a mass of air;
tr
dm is the mass of air
-1
Note 1 to entry: The unit of air kerma is J kg . The special name for the unit of air kerma is gray (Gy) – see ICRU
60 [4].
[SOURCE: IEC TR 60788:2004, rm-13-11]
3.2.8
air kerma rate
˙
𝐾𝐾
˙
𝑈𝑈𝐾𝐾
(3)
𝐾𝐾 =
𝑈𝑈𝑑𝑑
where
dK is the increment of air kerma in the time interval dt;
dt is the time interval
Note 1 to entry: The unit is J kg-1 s-1.
-1
Note 2 to entry: If the special name gray is used, the unit of air kerma rate is gray per second (Gy s ) - see [4].
[SOURCE: IEC TR 60788:2004, rm-13-54]
3.2.9
anti-scatter grid
device to be placed before the image reception area in order to reduce the incidence of
scattered radiation upon that area and thus increase the contrast in the X-ray pattern
[SOURCE: IEC TR 60788:2004, rm-32-06]
3.2.10
associated equipment
equipment other than those for the production and control of ionizing
radiation, but essential for its application
[SOURCE: IEC TR 60788:2004, rm-30-01]
3.2.11
attenuation
reduction of a radiation quantity upon passage of the radiation through matter resulting from all
types of interaction with this matter.
Note 1 to entry: Attenuation does not include the geometric reduction of the radiation quantity with distance from
the radiation source.
Note 2 to entry: The radiation quantity can be, for example, the particle flux density or the energy density.
[SOURCE: IEC TR 60788:2004, rm-12-08]
IEC 61267:2025 © IEC 2025
3.2.12
automatic exposure control
mode of operation in which one or more loading factors are controlled
automatically in order to obtain at a pre-selected location a desired quantity of radiation
[SOURCE: IEC TR 60788:2004, rm-36-46]
3.2.13
broad beam condition
arrangement for the measurement of a radiation quantity in a broad beam of ionizing radiation
[SOURCE: IEC TR 60788:2004, rm-37-25]
3.2.14
diaphragm
beam limiting device with either a fixed or an adjustable aperture in practically one plane
[SOURCE: IEC TR 60788:2004, rm-37-29]
3.2.15
effective focal spot
focal spot
perpendicular projection of the actual focal spot on the reference plane
[SOURCE: IEC TR 60788:2004, rm-20-13, modified - The note has been deleted.]
3.2.16
entrance surface
plane or curved surface through which the radiation enters an irradiated object
including any bolus which is present
[SOURCE: IEC TR 60788:2004, rm-37-17]
3.2.17
half-value layer
thickness of a specified material which attenuates under narrow beam conditions X- radiation
or gamma radiation with a particular radiation energy or with a particular spectrum to an extent
such that the kerma rate, exposure rate or absorbed dose rate is reduced to one half of the
value that is measured without the material
Note 1 to entry: The half-value layer is expressed in suitable submultiples of the metre together with the material.
[SOURCE: IEC TR 60788:2004, rm-13-42]
3.2.18
inherent filtration
quality equivalent filtration due to the irremovable materials through which the radiation beam
passes before emerging from a radiation source assembly or from components thereof
Note 1 to entry: For an X-ray tube assembly, the inherent filtration is expressed in thickness of a reference material
which, at a specified voltage and waveform, gives the same radiation quality in terms of first half-value layer.
[SOURCE: IEC TR 60788:2004, rm-13-46]
IEC 61267:2025 © IEC 2025
3.2.19
ionization chamber
ionization detector consisting of a chamber filled with a suitable gas, in which an electric field,
insufficient to induce gas multiplication, is provided for the collection at the electrodes of
charges associated with ions and the electrons produced in the sensitive volume of the detector
by ionizing radiation
[SOURCE: IEC TR 60788:2004, rm-51-03]
3.2.20
manufacturer
organization or individual who produces an equipment
[SOURCE: IEC TR 60788:2004, rm-85-03]
3.2.21
narrow beam condition
arrangement for the measurement of a radiation quantity in a narrow beam of ionizing radiation
[SOURCE: IEC TR 60788:2004, rm-37-23]
3.2.22
patient
person or animal undergoing medical examination or treatment
Note 1 to entry: For purposes of radiological protection, a person or animal is a patient only during the intentional
application of ionizing radiation to that person or animal.
[SOURCE: IEC TR 60788:2004, rm-62-03]
3.2.23
patient support
component such as a table top or arm rest, serving to support the
patient in order to allow the part of their body which is to be irradiated to be positioned or to be
displaced
[SOURCE: IEC TR 60788:2004, rm-30-02]
3.2.24
percentage ripple
ratio of the difference between the highest and the lowest values of
a rectified voltage waveform during a cycle of the supply to the highest value, expressed as a
percentage
[SOURCE: IEC TR 60788:2004, rm-36-17]
3.2.25
phantom
object behaving in essentially the same manner as tissue, with respect to
absorption or scattering of the ionizing radiation in question
Note 1 to entry: Phantoms are used, for example, for simulating practical conditions of measurement:
– for purposes of radiation protection;
– for evaluation the performances of diagnostic systems with respect to the radiation or to the object;
– for dosimetry.
[SOURCE: IEC TR 60788:2004, rm-54-01]
IEC 61267:2025 © IEC 2025
3.2.26
quality control
operational techniques and activities that are used to fulfil requirements for quality
[SOURCE: IEC TR 60788:2004, rm-70-07]
3.2.27
quality equivalent filtration
quantitative indication of the filtration effected by one or several layer(s) of reference material(s)
which, if substituted in a beam of specified radiation quality under narrow beam condition for
the material under consideration, give(s) the same radiation quality as gives the material under
consideration
Note 1 to entry: The quality equivalent filtration is expressed in suitable submultiples of the metre together with the
reference material(s) and the radiation quality of the incident beam.
[SOURCE: IEC TR 60788:2004, rm-13-45]
3.2.28
radiation beam
spatial region limited in solid angle and containing a flux of ionizing radiation
originating from a radiation source that is considered as a point source
EXAMPLE X-ray beam, gamma-ray beam, electron beam, neutron beam.
Note 1 to entry: Leakage radiation and scattered radiation are considered not to form a radiation beam.
[SOURCE: IEC TR 60788:2004, rm-37-05]
3.2.29
radiation beam axis
line through the centre of the radiation source and half way
between the effective edges of the beam limiting device
EXAMPLE X-ray beam axis, gamma-ray beam axis, neutron beam axis, electron beam axis.
Note 1 to entry: Usually, the radiation beam axis coincides within required tolerances with the reference axis of the
radiation source.
[SOURCE: IEC TR 60788:2004, rm-37-06]
3.2.30
radiation detector
equipment, generally sub-assembly, or substance which, in the presence of radiation, provides
by either direct or indirect means a signal or other indication suitable for use in measuring one
or more quantities of the incident radiation
[SOURCE: IEC TR 60788:2004, rm-51-01]
3.2.31
radiation field
area on a surface intersected by a radiation beam within which the radiation intensity exceeds
a specific or specified level
EXAMPLE X-ray field, gammy-ray field, electron field, neutron field.
[SOURCE: IEC TR 60788:2004, rm-37-07]
IEC 61267:2025 © IEC 2025
3.2.32
radiation source
radioactive source or part of equipment capable of emitting ionizing radiation
[SOURCE: IEC TR 60788:2004, rm-20-01]
3.2.33
radiology
science of ionizing radiation and its application
[SOURCE: IEC TR 60788:2004, rm-40-01]
3.2.34
reference axis
for a radiation source, line in the reference direction through the centre of the radiation source
[SOURCE: IEC TR 60788:2004, rm-37-03]
3.2.35
scattered radiation
ionizing radiation emitted by interaction of ionizing radiation with matter, the interaction being
accompanied by a reduction in radiation energy and/or by a change in direction of the radiation
[SOURCE: IEC TR 60788:2004, rm-11-13]
3.2.36
sensitive volume
part of a detector se
...