oSIST prEN IEC 61674:2023

SLOVENSKI STANDARD
oSIST prEN IEC 61674:2023
01-april-2023
Medicinska električna oprema - Dozimetri z ionizacijskimi komorami oziroma
polprevodniški detektorji, kot so uporabljeni pri rentgenskem diagnostičnem
slikanju
Medical electrical equipment - Dosimeters with ionization chambers and/or
semiconductor detectors as used in X-ray diagnostic imaging
Medizinische elektrische Geräte - Dosimeter mit Ionisationskammern und/oder
Halbleiterdetektoren für den Einsatz an diagnostischen Röntgeneinrichtungen
Appareils électromédicaux - Dosimètres à chambres d’ionisation et/ou à détecteurs
semiconducteurs utilisés en imagerie de diagnostic à rayonnement X
Ta slovenski standard je istoveten z: prEN IEC 61674:2023
ICS:
11.040.50 Radiografska oprema Radiographic equipment
17.240 Merjenje sevanja Radiation measurements
oSIST prEN IEC 61674:2023 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN IEC 61674:2023

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oSIST prEN IEC 61674:2023
62C/865/CDV

COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 61674 ED3
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2023-01-27 2023-04-21
SUPERSEDES DOCUMENTS:
62C/844/CD, 62C/862A/CC

IEC SC 62C : EQUIPMENT FOR RADIOTHERAPY, NUCLEAR MEDICINE AND RADIATION DOSIMETRY
SECRETARIAT: SECRETARY:
Germany Ms Regina Geierhofer
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:


Other TC/SCs are requested to indicate their interest, if any,
in this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft for
Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.

This document is still under study and subject to change. It should not be used for reference purposes.
Recipients of this document are invited to submit, with their comments, notification of
• any relevant patent rights of which they are aware and to provide supporting documentation ,
• any relevant “in some countries” clauses to be included should this proposal proceed. Recipients are reminded
that the enquiry stage is the final stage for submitting "in some countries" clauses. See AC/22/2007.

TITLE:
Medical electrical equipment - Dosimeters with ionization chambers and/or semiconductor detectors as
used in X-ray diagnostic imaging

PROPOSED STABILITY DATE: 2027

Copyright © 2022 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to download this
electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee
positions. You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose
without permission in writing from IEC.

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62C/865/CDV – 2 – IEC 61674 CDV © IEC 2023
NOTE FROM TC/SC OFFICERS:

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IEC 61674 CDV © IEC 2023 – 3 – 62C/865/CDV
1 CONTENTS
2 FOREWORD . 5
3 INTRODUCTION . 7
4 1 Scope and object . 8
5 1.1 Scope . 8
6 1.2 Object . 8
7 2 Normative references . 8
8 3 Terms and definitions . 9
9 4 General requirements . 16
10 4.1 Performance requirements . 16
11 4.2 REFERENCE VALUES and STANDARD TEST VALUES . 16
12 4.3 General test conditions . 17
13 4.3.1 STANDARD TEST CONDITIONS . 17
14 4.3.2 Statistical fluctuations . 17
15 4.3.3 STABILIZATION TIME . 18
16 4.3.4 Adjustments during test . 18
17 4.3.5 Batteries . 18
18 4.4 Constructional requirements as related to performance . 18
19 4.4.1 Components . 18
20 4.4.2 Display . 19
21 4.4.3 Indication of battery condition . 19
22 4.4.4 Indication of polarizing voltage failure . 19
23 4.4.5 Over-ranging . 19
24 4.4.6 MEASURING ASSEMBLIES with multiple DETECTOR ASSEMBLIES . 20
25 4.4.7 Radioactive STABILITY CHECK DEVICE . 20
26 4.5 UNCERTAINTY of measurement . 20
27 5 Limits of PERFORMANCE CHARACTERISTICS . 21
28 5.1 Linearity . 21
29 5.2 Repeatability . 21
30 5.2.1 General . 21
31 5.2.2 Repeatability in the ATTENUATED BEAM . 21
32 5.2.3 Repeatability in the UNATTENUATED BEAM . 22
33 5.3 RESOLUTION of reading . 22
34 5.4 STABILIZATION TIME . 22
35 5.5 Effect of pulsed radiation on AIR KERMA and AIR KERMA LENGTH PRODUCT
36 measurements . 22
37 5.6 Stability . 23
38 5.6.1 Long term stability . 23
39 5.6.2 Accumulated dose stability . 23
40 5.7 Measurements with a radioactive STABILITY CHECK DEVICE . 23
41 6 LIMITS OF VARIATION for effects of INFLUENCE QUANTITIES . 24
42 6.1 General . 24
43 6.2 Energy dependence of RESPONSE . 24
44 6.3 AIR KERMA RATE dependence of AIR KERMA and AIR KERMA LENGTH PRODUCT
45 measurements . 25
46 6.4 Dependence of DETECTOR RESPONSE on angle of incidence of radiation . 26
47 6.4.1 Non-CT detectors . 26

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48 6.4.2 CT DETECTORS . 26
49 6.5 Operating voltage . 26
50 6.5.1 Mains-operated DOSIMETERS . 26
51 6.5.2 Battery-operated DOSIMETERS . 26
52 6.5.3 Mains rechargeable, battery-operated DOSIMETERS . 26
53 6.6 Air pressure . 27
54 6.7 Air pressure EQUILIBRATION TIME of the RADIATION DETECTOR . 27
55 6.8 Temperature and humidity . 27
56 6.9 Electromagnetic compatibility . 28
57 6.9.1 ELECTROSTATIC DISCHARGE . 28
58 6.9.2 Radiated electromagnetic fields . 28
59 6.9.3 CONDUCTED DISTURBANCES induced by bursts and radio frequencies . 29
60 6.9.4 Voltage dips, short interruptions and voltage VARIATIONS . 29
61 6.10 Field size . 29
62 6.11 EFFECTIVE LENGTH and spatial uniformity of RESPONSE of CT DOSIMETERS . 29
63 7 Marking . 30
64 7.1 DETECTOR ASSEMBLY . 30
65 7.2 MEASURING ASSEMBLY . 30
66 7.3 Radioactive STABILITY CHECK DEVICE . 30
67 8 ACCOMPANYING DOCUMENTS . 31
68 Annex A (informative) COMBINED STANDARD UNCERTAINTY for dosimeter performance . 33
69 Index of defined terms . 34
70
71 Table 1 – REFERENCE and STANDARD TEST CONDITIONS . 17
72 Table 2 – Number of readings required to detect true differences  (95 % confidence
73 level) between two sets of instrument readings . 18
74 Table 3 – Maximum values for the COEFFICIENT OF VARIATION, v , for measurements
max
75 in the attenuated beam . 21
76 Table 4 – Maximum values for the COEFFICIENT OF VARIATION, v , for measurements
max
77 in the unattenuated beam . 22
78 Table 5 – LIMITS OF VARIATION for the effects of INFLUENCE QUANTITIES . 24
79 Table 6 – Climatic conditions . 28
80 Table A.1 – Estimation of COMBINED STANDARD UNCERTAINTY for dosimeter performance . 33
81
82

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83 INTERNATIONAL ELECTROTECHNICAL COMMISSION
84 ____________
85
86 MEDICAL ELECTRICAL EQUIPMENT –
87 DOSIMETERS WITH IONIZATION CHAMBERS AND/OR
88 SEMICONDUCTOR DETECTORS AS USED
89 IN X-RAY DIAGNOSTIC IMAGING
90
91 FOREWORD
92 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
93 all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
94 international co-operation on all questions concerning standardization in the electrical and electronic fields. To
95 this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
96 Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
97 Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
98 in the subject dealt with may participate in this preparatory work. International, governmental and non-
99 governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
100 with the International Organization for Standardization (ISO) in accordance with conditions determined by
101 agreement between the two organizations.
102 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
103 consensus of opinion on the relevant subjects since each technical committee has representation from all
104 interested IEC National Committees.
105 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
106 Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
107 Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
108 misinterpretation by any end user.
109 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
110 transparently to the maximum extent possible in their national and regional publications. Any divergence
111 between any IEC Publication and the corresponding national or regional publication shall be clearly indica ted in
112 the latter.
113 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
114 assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
115 services carried out by independent certification bodies.
116 6) All users should ensure that they have the latest edition of this publication.
117 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
118 members of its technical committees and IEC National Committees for any personal injury, property damage or
119 other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
120 expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
121 Publications.
122 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
123 indispensable for the correct application of this publication.
124 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
125 patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
126 International Standard IEC 61674 has been prepared by subcommittee 62C: Equipment for
127 radiotherapy, nuclear medicine and radiation dosimetry, of IEC technical committee 62:
128 Electrical equipment in medical practice.
129 This second edition cancels and replaces the first edition of IEC 61674. This edition
130 constitutes a technical revision.
131 The text of this standard is based on the following documents:
FDIS Report on voting
62C/551/FDIS 62C/555/RVD
132
133 Full information on the voting for the approval of this standard can be found in the report on
134 voting indicated in the above table.

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135 This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
136 In this standard, the following print types are used:
137 – Requirements and definitions: roman type.
138 – Test specifications: italic type.
139 – Informative material appearing outside of tables, such as notes, examples and references: in smaller type.
140 Normative text of tables is also in a smaller type.
141 – TERMS DEFINED IN CLAUSE 3 OF IEC 60601-1, IN THIS PARTICULAR STANDARD OR AS NOTED:
142 SMALL CAPITALS.
143 The verbal forms used in this standard conform to usage described in Annex H of the ISO/IEC
144 Directives, Part 2. For the purposes of this standard, the auxiliary verb:
145 – “shall” means that compliance with a requirement or a test is mandatory for compliance
146 with this standard;
147 – “should” means that compliance with a requirement or a test is recommended but is not
148 mandatory for compliance with this standard;
149 – “may” is used to describe a permissible way to achieve compliance with a requirement or
150 test.
151 The committee has decided that the contents of this publication will remain unchanged until
152 the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
153 related to the specific publication. At this date, the publication will be
154 • reconfirmed,
155 • withdrawn,
156 • replaced by a revised edition, or
157 • amended.
158
159
160

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161 INTRODUCTION
162 Diagnostic radiology is the largest contributor to man-made IONIZING RADIATION to which the
163 public is exposed. The reduction in the exposure received by PATIENTS undergoing medical
164 radiological examinations or procedures has therefore become a central issue in recent years.
165 The PATIENT dose will be minimized when the X-ray producing equipment is correctly adjusted
166 for image quality and radiation output. These adjustments require that the routine
167 measurement of AIR KERMA, AIR KERMA LENGTH PRODUCT and/or AIR KERMA RATE be made
168 accurately. The equipment covered by this standard plays an essential part in achieving the
169 required accuracy. The DOSIMETERS used for adjustment and control measurements must be
170 of satisfactory quality and must therefore fulfil the special requirements laid down in this
171 standard.
172

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173 MEDICAL ELECTRICAL EQUIPMENT –
174 DOSIMETERS WITH IONIZATION CHAMBERS AND/OR
175 SEMICONDUCTOR DETECTORS AS USED
176 IN X-RAY DIAGNOSTIC IMAGING
177
178
179
180 1 Scope and object
181 1.1 Scope
182 This International Standard specifies the performance and some related constructional
183 requirements of DIAGNOSTIC DOSIMETERS intended for the measurement of AIR KERMA, AIR
184 KERMA LENGTH PRODUCT or AIR KERMA RATE, in photon radiation fields used in medical X-ray
185 imaging, such as RADIOGRAPHY, RADIOSCOPY and COMPUTED TOMOGRAPHY (CT), for X-radiation
186 with generating potentials in the range of 20 kV to 150 kV.
187 This International Standard is applicable to the performance of DOSIMETERS with VENTED
188 IONIZATION CHAMBERS and/or SEMICONDUCTOR DETECTORS as used in X-ray diagnostic imaging.
189 1.2 Object
190 The object of this standard is:
191 a) to establish requirements for a satisfactory level of performance for DIAGNOSTIC
192 DOSIMETERS, and
193 b) to standardize the methods for the determination of compliance with this level of
194 performance.
195 This standard is not concerned with the safety aspects of DOSIMETERS. The DIAGNOSTIC
196 DOSIMETERS covered by this standard are not intended for use in the PATIENT ENVIRONMENT
197 and, therefore, the requirements for electrical safety applying to them are contained in
198 IEC 61010-1.
199 2 Normative references
200 The following documents, in whole or in part, are normatively referenced in this document and
201 are indispensable for its application. For dated references, only the edition cited applies. For
202 undated references, the latest edition of the referenced document (including any
203 amendments) applies.
204 IEC 60050 (all parts), International Electrotechnical Vocabulary (available at
205 )
206 IEC 60601-1:2005, Medical electrical equipment – Part 1: General requirements for basic
207 safety and essential performance
208 IEC 60601-1-3:2008, Medical electrical equipment – Part 1-3: General requirements for basic
209 safety and essential performance – Collateral standard: Radiation protection in diagnostic
210 X-ray equipment
211 IEC 60417, Graphical symbols for use on equipment (Available at: 212 symbols.info/equipment>
213 IEC 60731:2011, Medical electrical equipment – Dosimeters with ionization chambers as used
214 in radiotherapy

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215 IEC 60788:2004, Medical electrical equipment – Glossary of defined terms
216 IEC 61000-4 (all parts) Electromagnetic compatibility (EMC) – Part 4: Testing and measuring
217 techniques
218 IEC 61000-4-2, Electromagnetic compatibility (EMC) – Part 4-2: Testing and measurement
219 techniques – Electrostatic discharge immunity test
220 IEC 61000-4-3, Electromagnetic compatibility (EMC) – Part 4-3: Testing and measurement
221 techniques – Radiated, radio-frequency, electromagnetic field immunity test
222 IEC 61000-4-4, Electromagnetic compatibility (EMC) – Part 4-4: Testing and measurement
223 techniques – Electrical fast transient/burst immunity test
224 IEC 61000-4-6, Electromagnetic compatibility (EMC) – Part 4-6: Testing and measurement
225 techniques – Immunity to conducted disturbances induced by radio-frequency fields
226 IEC 61000-4-11, Electromagnetic compatibility (EMC) – Part 4-11: Testing and measurement
227 techniques – Voltage dips, short interruptions and voltage variations immunity tests
228 IEC 61187, Electrical and electronic measuring equipment – Documentation
229 IEC 61267:2005, Medical diagnostic X-ray equipment – Radiation conditions for use in the
230 determination of characteristics
231 ISO/IEC GUIDE 98-3:2008, Uncertainty of measurement – Part 3: Guide to the expression of
232 uncertainty in measurement (GUM:1995)
233 ISO/IEC Guide 99:2007, International vocabulary of metrology – Basic and general concepts
234 and associated terms (VIM)
235 ISO 3534-1:2006, Statistics – Vocabulary and symbols – Part 1: General statistical terms and
236 terms used in probability
237 3 Terms and definitions
238 For the purposes of this document, the terms and definitions given in IEC/TR 60788:2004 and
239 the following apply.
240 3.1
241 DIAGNOSTIC DOSIMETER
242 DOSIMETER
243 equipment which uses IONIZATION CHAMBERS and/or SEMICONDUCTOR DETECTORS for the
244 measurement of AIR KERMA, AIR KERMA LENGTH PRODUCT and/or AIR KERMA RATE in the beam of
245 an X-RAY EQUIPMENT used for diagnostic medical radiological examinations
246 Note 1 to entry: A DIAGNOSTIC DOSIMETER contains the following components:
247 – one or more DETECTOR ASSEMBLIES which may or may not be an integral part of the MEASURING ASSEMBLY;
248 – a MEASURING ASSEMBLY;
249 – one or more STABILITY CHECK DEVICES (optional).
250 3.1.1
251 DETECTOR ASSEMBLY
252 RADIATION DETECTOR and all other parts to which the RADIATION DETECTOR is permanently
253 attached, except the MEASURING ASSEMBLY

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254 Note 1 to entry: The DETECTOR ASSEMBLY normally includes:
255 – the RADIATION DETECTOR and the stem (or body) on which the RADIATION DETECTOR is permanently mounted (or
256 embedded);
257 – the electrical fitting and any permanently attached cable or pre-amplifier.
258 3.1.1.1
259 RADIATION DETECTOR
260 element which transduces AIR KERMA, AIR KERMA LENGTH PRODUCT or AIR KERMA RATE into a
261 measurable electrical signal
262 Note 1 to entry: A radiation detector may be either an ionization chamber or a semiconductor detector.
263 3.1.1.1.1
264 IONIZATION CHAMBER
265 CHAMBER
266 ionizing RADIATION DETECTOR consisting of a CHAMBER filled with air, in which an electric field
267 insufficient to produce gas multiplication is provided for the collection at the electrodes of
268 charges associated with the ions and the ELECTRONS produced in the measuring volume of the
269 detector by IONIZING RADIATION
270 Note 1 to entry: An IONIZATION CHAMBER can be sealed or vented.
271 Note 2 to entry: Vented IONIZATION CHAMBERS are constructed in such a way as to allow the air inside the
272 measuring volume to communicate freely with the atmosphere, so that corrections to the RESPONSE for changes in
273 air density need to be made.
274 Note 3 to entry: Sealed IONIZATION CHAMBERS are not suitable, because the necessary wall thickness of a sealed
275 CHAMBER may cause an unacceptable energy dependence of the RESPONSE and because the long term stability of
276 sealed CHAMBERS is not guaranteed.
277 [SOURCE: IEC 60731:2011, 3.1.1.1, modified – three new notes to entry have replaced the
278 two original notes.]
279 3.1.1.1.2
280 VENTED IONIZATION CHAMBER
281 IONIZATION CHAMBER constructed in such a way as to allow the air inside the measuring volume
282 to communicate freely with the atmosphere such that corrections to the RESPONSE for changes
283 in air density need to be made
284 [SOURCE: IEC 60731:2011, 3.1.1.1.3, modified – the term has been changed from "vented
285 chamber" to "VENTED IONIZATION CHAMBER". ]
286 3.1.1.1.3
287 SEMICONDUCTOR DETECTOR
288 semiconductor device that utilises the production and motion of electron-hole pairs in a
289 charge carrier depleted region of the semiconductor for the detection and measurem ent of
290 IONIZING RADIATION
291 Note 1 to entry: The production of electron-hole pairs is caused either
292 – directly by interaction of the IONIZING RADIATION with the semiconductor material, or
293 – indirectly by first converting the incident radiation energy to light in a scintillator material directly in front of and
294 optically coupled to a semiconductor photodiode, which then produces the electrical signal.
295 3.1.2
296 MEASURING ASSEMBLY
297 device to measure the electrical signal from the RADIATION DETECTOR and convert it into a form
298 suitable for displaying the values of DOSE or KERMA or their corresponding rates
299 [SOURCE: IEC 60731:2011, 3.1.2. modified – the term IONIZATION CHAMBER in the original
300 definition has been replaced by the term RADIATION DETECTOR]

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301 3.1.3
302 STABILITY CHECK DEVICE
303 device which enables the stability of RESPONSE of the MEASURING ASSEMBLY and/or CHAMBER
304 ASSEMBLY to be checked
305 Note 1 to entry: The STABILITY CHECK DEVICE may be a purely electrical device, or a radiation source, or it may
306 include both.
307 [SOURCE: IEC 60731:2011, 3.1.3]
308 3.1.4
309 CT DOSIMETER
310 DIAGNOSTIC DOSIMETER which uses long narrow IONIZATION CHAMBERS and/or SEMICONDUCTOR
311 DETECTORS for the measurement of AIR KERMA integrated along the length of the DETECTOR
312 when the DETECTOR is exposed to a cross-sectional X-ray scan of a computed tomograph
313 Note 1 to entry: A CT DOSIMETER contains the following components:
314 – one or more DETECTOR ASSEMBLIES;
315 – a MEASURING ASSEMBLY.
316 3.1.5
317 CT DETECTOR
318 RADIATION DETECTOR which is used for CT dosimetry
319 3.2
320 INDICATED VALUE
321 value of a quantity derived from the reading of an instrument together with any scale factors
322 indicated on the control panel of the instrument
323 [SOURCE: IEC 60731:2011, 3.2]
324 3.3
325 TRUE VALUE
326 value of the physical quantity to be measured by an instrument
327 [SOURCE: IEC 60731:2011, 3.3]
328 3.4
329 CONVENTIONAL TRUE VALUE
330 value used instead of the TRUE VALUE when calibrating or determining the performance of an
331 instrument, since in practice the TRUE VALUE is unknown and unknowable
332 Note 1 to entry: The CONVENTIONAL TRUE VALUE will usually be the value determined by the WORKING STANDARD
333 with which the instrument under test is being compared.
334 [SOURCE: IEC 60731:2011, 3.4]
335 3.5
336 MEASURED VALUE
337 best estimate of the TRUE VALUE of a quantity, being derived from the INDICATED VALUE of an
338 instrument together wit
...