IEC 60601-2-44:2001

INTERNATIONAL IEC
STANDARD
60601-2-44
Second edition
2001-06
Medical electrical equipment –
Part 2-44:
Particular requirements for the safety of
X-ray equipment for computed tomography
Appareils électromédicaux –
Partie 2-44:
Règles particulières de sécurité pour les équipements
à rayonnement X de tomodensitométrie

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INTERNATIONAL IEC
STANDARD
60601-2-44
Second edition
2001-06
Medical electrical equipment –
Part 2-44:
Particular requirements for the safety of
X-ray equipment for computed tomography
Appareils électromédicaux –
Partie 2-44:
Règles particulières de sécurité pour les équipements
à rayonnement X de tomodensitométrie

 IEC 2001  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
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Commission Electrotechnique Internationale
PRICE CODE
V
International Electrotechnical Commission
For price, see current catalogue

– 2 – 60601-2-44 IEC:2001(E)

CONTENTS
FOREWORD 4
..........................................................................................................................

SECTION 1: GENERAL
1 Scope and object 6
.............................................................................................................

1.1 Scope 6
.....................................................................................................................

1.2 Object 6
....................................................................................................................
1.3 Particular Standards 7
...............................................................................................
2 Terminology and definitions 8
.............................................................................................
3 General requirements 10
....................................................................................................
5 Classification 10
.................................................................................................................
6 Identification, marking and documents 11
...........................................................................
6.1 Marking on the outside of EQUIPMENT or EQUIPMENT parts 11
......................................
6.7 Indicator lights and push-buttons 11
..........................................................................
6.8 ACCOMPANYING DOCUMENTS 12
...................................................................................
SECTION 2: ENVIRONMENTAL CONDITIONS
10 Environmental conditions 13
...............................................................................................
SECTION 3: PROTECTION AGAINST ELECTRIC SHOCK HAZARDS
15 Limitation of voltage and/or energy 14
.................................................................................
16 ENCLOSURES and PROTECTIVE COVERS 14
............................................................................
19 Continuous LEAKAGE CURRENTS and PATIENT AUXILIARY CURRENTS 15
...................................
19.3 Allowable values 15
...................................................................................................
20 Dielectric strength 15
..........................................................................................................
20.3 Values of test voltages 15
..........................................................................................
20.4 Tests 16
....................................................................................................................
SECTION 4: PROTECTION AGAINST MECHANICAL HAZARDS
22 Moving parts 17
..................................................................................................................

27 Pneumatic and hydraulic power 18
......................................................................................
SECTION 5: PROTECTION AGAINST HAZARDS FROM UNWANTED OR
EXCESSIVE RADIATION
29 X-RADIATION 19
...................................................................................................................
36 Electromagnetic compatibility 26
.........................................................................................

60601-2-44 © IEC:2001(E) – 3 –

SECTION 6: PROTECTION AGAINST HAZARDS OF IGNITION OF

FLAMMABLE ANAESTHETIC MIXTURES

SECTION 7: PROTECTION AGAINST EXCESSIVE TEMPERATURES AND

OTHER SAFETY HAZARDS
42 Excessive temperatures 26
.................................................................................................

SECTION 8: ACCURACY OF OPERATING DATA AND PROTECTION
AGAINST HAZARDOUS OUTPUT
50 Accuracy of operating data 27
.............................................................................................
50.101 Accuracy of radiation output 27
..............................................................................
50.102 Accuracy of recorded examination data 27
.............................................................
51 Protection against hazardous output 28
..............................................................................
SECTION 9: ABNORMAL OPERATION AND FAULT CONDITIONS;
ENVIRONMENTAL TESTS
SECTION 10: CONSTRUCTIONAL REQUIREMENTS
56 Components and general assembly 28
................................................................................
56.7 Batteries 29
...............................................................................................................
57 MAINS PARTS, components and layout 29
.............................................................................
57.10 CREEPAGE DISTANCES and AIR CLEARANCES 29
..........................................................
Tables
101 HALF-VALUE LAYERS in CT SCANNERS 24
..............................................................................
Figures
101 Coordinate system 9
...........................................................................................................
Annex AA (normative) Terminology – Index of defined terms 30
...............................................
Annex BB (informative) Choosing LOADING FACTORS for tests 33
..............................................
Bibliography 34
.........................................................................................................................

– 4 – 60601-2-44 IEC:2001(E)

INTERNATIONAL ELECTROTECHNICAL COMMISSION

___________
MEDICAL ELECTRICAL EQUIPMENT –

Part 2-44: Particular requirements for the safety of

X-ray equipment for computed tomography

FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60601-2-44 has been prepared by subcommittee 62B: Diagnostic
imaging equipment, of IEC technical committee 62: Electrical equipment in medical practice.
This second edition cancels and replaces the first edition published in 1999 and constitutes a
technical revision.
The text of this Particular Standard is based on the following documents:
FDIS Report of voting
62B/426/FDIS 62B/437/RVD
Full information on the voting for the approval of this standard can be found in the report of
voting indicated in the above table.
Annex AA forms an integral part of this standard.
Annex BB is for information only.

60601-2-44 © IEC:2001(E) – 5 –

In this standard, the following print types are used:

– requirements, compliance with which can be tested and definitions: roman type:

– explanations, advice, notes, general statements and exceptions: smaller type;

– test specifications and headings of subclauses: italic type;

– TERMS DEFINED IN CLAUSE 2 OF THE GENERAL STANDARD OR IN IEC 60788: SMALL CAPITALS.

The committee has decided that the contents of this publication will remain unchanged until

2002-12. At this date, the publication will be

• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.
The contents of the corrigendum of April 2006 have been included in this copy.

– 6 – 60601-2-44 IEC:2001(E)

MEDICAL ELECTRICAL EQUIPMENT –

Part 2-44: Particular requirements for the safety of

X-ray equipment for computed tomography

SECTION 1: GENERAL
The clauses and subclauses of this section of the General Standard apply except as follows:

1 Scope and object
This clause of the General Standard applies except as follows:
1.1 Scope
Addition:
This Particular Standard applies to X-RAY EQUIPMENT for COMPUTED TOMOGRAPHY (CT
SCANNERS).
It includes safety requirements for the X-RAY GENERATOR, and those where HIGH VOLTAGE
GENERATORS are integrated with an X-RAY TUBE ASSEMBLY.
1.2 Object
Replacement:
The object of this standard is to establish particular requirements to ensure safety, and to
SCANNERS
specify methods for demonstrating compliance with those requirements, for CT .
NOTE 1 Requirements for reproducibility, linearity, constancy and accuracy are given because of their relationship
to the quality and quantity of the IONIZING RADIATION produced and are confined to those considered necessary for
safety.
NOTE 2 Both the levels for compliance and the tests prescribed to determine compliance reflect the fact that the
safety of HIGH-VOLTAGE GENERATORS is not sensitive to small differences in levels of performance. The combinations
of LOADING FACTORS specified for the tests are therefore limited in number but chosen from experience as being
LOADING FACTORS
appropriate in most cases. It is considered important to standardize the choice of combinations of
so that comparison can be made between tests performed in different places on different occasions. However,
combinations other than those specified could be of equal technical validity.
NOTE 3 The safety philosophy on which this standard is based is described in the introduction to the General
Standard and in IEC 60513.
RADIOLOGICAL PROTECTION
NOTE 4 Concerning it has been assumed in the preparation of this standard that
MANUFACTURERS USERS
and do accept the general principles of the ICRP as stated in ICRP 60, 1990,
1)
paragraph 112, namely:
"(a) No practice involving exposures to radiation should be adopted unless it produces sufficient benefit to the
exposed individuals or to society to offset the radiation detriment it causes. (The justi
...