IEC 60601-1-8:2003
(Main)Medical electrical equipment — Part 1-8: General requirements for safety — Collateral standard: General requirements, tests and guidance for alarm systems in medical electrical equipment and medical electrical systems
Medical electrical equipment — Part 1-8: General requirements for safety — Collateral standard: General requirements, tests and guidance for alarm systems in medical electrical equipment and medical electrical systems
Appareils électromédicaux — Partie 1-8: Règles générales de sécurité — Norme collatérale: Règles générales, essais et guides pour les systèmes d'alarme dans l'équipement électromédical et les systèmes électromédicaux
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INTERNATIONAL IEC
STANDARD
60601-1-8
First edition
2003-08
Medical electrical equipment –
Part 1-8:
General requirements for safety –
Collateral standard:
General requirements, tests and guidance
for alarm systems in medical electrical
equipment and medical electrical systems
Appareils électromédicaux –
Partie 1-8:
Règles générales de sécurité –
Norme collatérale:
Règles générales, essais et guides
pour les systèmes d'alarme dans l'équipement
électromédical et les systèmes électromédicaux
Reference number
IEC 60601-1-8:2003(E)
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Publication numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1.
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INTERNATIONAL IEC
STANDARD
60601-1-8
First edition
2003-08
Medical electrical equipment –
Part 1-8:
General requirements for safety –
Collateral standard:
General requirements, tests and guidance
for alarm systems in medical electrical
equipment and medical electrical systems
Appareils électromédicaux –
Partie 1-8:
Règles générales de sécurité –
Norme collatérale:
Règles générales, essais et guides
pour les systèmes d'alarme dans l'équipement
électromédical et les systèmes électromédicaux
IEC 2003 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, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
PRICE CODE
XB
For price, see current catalogue
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– 2 – 60601-1-8 IEC:2003(E)
CONTENTS
FOREWORD . 4
INTRODUCTION .6
SECTION ONE – GENERAL
1 Scope and object . 7
1.201 Scope . 7
1.202 Object . 8
1.203 Relationship to other standards. 7
1.203.1 IEC 60601-1 . 7
1.203.2 Particular standards . 7
1.203.3 Normative references . 8
2 Terminology and definitions . 8
6 Identification, marking and documents .12
6.3 Marking of controls and instruments .12
6.7 Indicator lights and push-buttons.12
6.8.1 ACCOMPANYING DOCUMENTS .12
6.8.2 Instructions for use .12
6.8.3 Technical description.13
SECTION TWO TO TEN – NOT USED
201 ALARM SYSTEMS .13
201.1 ALARM CONDITION .13
201.1.1 General .13
201.1.2 ALARM CONDITION priority .13
201.2 Disclosures for INTELLIGENT ALARM SYSTEM.14
201.3 Generation of ALARM SIGNALS .14
201.3.1 General .14
201.3.2 Visual ALARM SIGNALS .14
201.3.3 Auditory ALARM SIGNALS .15
201.3.4 Characteristics of verbal ALARM SIGNALS .18
201.4 Disclosure of delays .18
201.4.1 ALARM SYSTEM delays .18
201.4.2 Delays to or from a DISTRIBUTED ALARM SYSTEM.19
201.5 ALARM PRESETS.19
201.5.1 General requirements .19
201.5.2 Manufacturer-configured ALARM PRESETS.20
201.5.3 USER- and OPERATOR-configured ALARM PRESETS.20
201.5.4 DEFAULT ALARM PRESET .21
201.5.5 Interruptions of less than or equal to 30 s .21
201.6 ALARM LIMIT.22
201.6.1 General requirements .22
201.6.2 Adjustable ALARM LIMIT .22
201.7 ALARM SYSTEM security .22
201.8 ALARM SIGNAL inactivation states .23
201.8.1 General .23
201.8.2 Termination of inactivation of ALARM SIGNALS.23
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60601-1-8 IEC:2003(E) – 3 –
201.8.3 Indication and access .23
201.9 ALARM RESET .24
201.10 NON-LATCHING and LATCHING ALARM SIGNALS .24
201.11 DISTRIBUTED ALARM SYSTEM .25
201.11.1 Existence OF DISTRIBUTED ALARM SYSTEM .25
201.11.2 Requirements for DISTRIBUTED ALARM SYSTEM communication of
ALARM CONDITIONS .25
201.12 ALARM CONDITION logging.26
Appendix D (normative) Symbols on marking .27
Annex AAA (informative) Rationale and guidance.32
Annex BBB (informative) Cross-reference of identification, marking, and documents.61
Annex CCC (informative) Guidance for auditory ALARM SIGNALS.64
Annex DDD (informative) Verbal ALARM SIGNALS .65
Annex EEE (normative) Reserved melodies for ALARM SIGNALS.67
Bibliography.68
Index of defined terms.70
Figure 201 – Illustration of temporal characteristics of auditory ALARM SIGNALS.17
Figure AAA.1 – Graphical representation of components of ALARM SYSTEM delay.48
Table 201 – ALARM CONDITION priorities .13
Table 202 – Characteristics of alarm indicator lights .15
Table 203 – Characteristics of the BURST of auditory ALARM SIGNALS .16
Table 204 – Characteristics of the PULSE of auditory ALARM SIGNALS .16
Table 205 – ALARM SIGNAL inactivation states.24
Table D.201 – Graphical symbols for ALARM SYSTEMS .28
Table D.202 – Alternative ALARM SYSTEM related markings .31
Table AAA.1 – Reference interpretation of Table EEE.1 .60
Table AAA.2 – Reference interpretation of Table EEE.2 .60
Table BBB.1 – Cross-reference of Marking.61
Table BBB.2 – Cross-reference of ACCOMPANYING DOCUMENTS.62
Table BBB.3 – Cross-reference of instructions for use .63
Table BBB.4 – Cross-reference of technical description .63
Table CCC.1 – Attributes of perceived urgency .64
Table EEE.1 – Equipment encoded auditory ALARM SIGNALS categorized by ALARM
CONDITION and priority complying with Tables 203 and 204.67
Table EEE.2 – Auditory LOW PRIORITY ALARM SIGNAL complying with Tables 203 and 204.67
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INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
MEDICAL ELECTRICAL EQUIPMENT –
Part 1-8: General requirements for safety –
Collateral Standard:
General requirements, tests and guidance for alarm systems
in medical electrical equipment and medical electrical systems
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, and Guides (hereafter referred to as “IEC 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 Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International standard IEC 60601-1-8 has been prepared by a Joint Working Group of IEC
subcommittee 62A: Common aspects of electrical equipment used in medical practice, of
IEC technical committee 62: Electrical equipment in medical practice, and ISO subcommittee
SC3: Lung ventilators and related devices of ISO technical committee 121: Anaesthetic and
respiratory equipment.
It is published as double logo standard.
This first edition constitutes a collateral standard to IEC 60601-1: Medical electrical
equipment – Part 1: General requirements for safety, hereinafter referred to as the general
standard.
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60601-1-8 IEC:2003(E) – 5 –
This standard replaces the following standards:
ISO 9703-1 Anesthesia and respiratory care alarm signals – Part 1: Visual alarm signals
ISO 9703-2 Anesthesia and respiratory care alarm signals – Part 2: Auditory alarm signals
ISO 9703-3 Anesthesia and respiratory care alarm signals – Part 3: Guidance on
application of alarms
The text of this collateral standard is based on the following documents:
FDIS Report on voting
62A/424/FDIS 62A/432/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table. In ISO, the standard has been approved by 16 P-members
out of 18 having cast a vote.
In the 60601 series of publications, collateral standards specify general requirements for
safety applicable to:
– a subgroup of MEDICAL ELECTRICAL EQUIPMENT (e.g. radiological equipment); or
– a specific characteristic of all MEDICAL ELECTRICAL EQUIPMENT, not fully addressed in the
general standard (e.g. alarm systems).
The numbering of sections, clauses and subclauses of this collateral standard corresponds
with that of the general standard.
Clauses, subclauses, tables, and figures which are additional to those of the general standard
are numbered starting from 201; additional annexes are lettered AAA, BBB, etc., and
additional items aaa), bbb), etc.
In this collateral standard, the following print types are used:
– requirements and definitions: roman type;
– notes, examples, explanations, advice, introductions, general statements and references: smaller roman type;
– test specifications and guidance in Annex AAA: italic type; and
– TERMS DEFINED IN CLAUSE 2 OF THE GENERAL STANDARD, IN THIS COLLATERAL STANDARD OR AS
NOTED: SMALL CAPITALS.
The requirements are followed by specifications for the relevant tests.
Clauses and subclauses for which a rationale is provided in informative Annex AAA are
marked with an asterisk (*).
The committee has decided that the contents of this publication will remain unchanged until
2008. At this date, the publication will be
− reconfirmed;
− withdrawn;
− replaced by a revised edition, or
− amended.
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INTRODUCTION
MEDICAL ELECTRICAL EQUIPMENT and MEDICAL ELECTRICAL SYSTEMS are increasingly used in
medical practice. ALARM SIGNALS are frequently used to indicate unsatisfactory physiological
PATIENT states, unsatisfactory functional states of the MEDICAL ELECTRICAL EQUIPMENT or
MEDICAL ELECTRICAL SYSTEM or to warn the OPERATOR of potential hazards to the PATIENT or
OPERATOR due to the MEDICAL ELECTRICAL EQUIPMENT or MEDICAL ELECTRICAL SYSTEM.
INFORMATION SIGNALS convey information that is independent of an ALARM CONDITION.
Surveys of healthcare personnel have indicated significant discontent with ALARM SIGNALS.
Problems include difficulty in identifying the source of an ALARM SIGNAL, loud and distracting
1
ALARM SIGNALS, and the high incidence of FALSE POSITIVE or NEGATIVE ALARM CONDITIONS [16] .
Surveys of manufacturers of medical monitors demonstrated a wide variety of DEFAULT ALARM
PRESETS. The leading reason for disabling ALARM SIGNALS is the large number of ALARM
SIGNALS associated with FALSE POSITIVE ALARM CONDITIONS. See also bibliography.
Safety of PATIENTS depends on the ability of the OPERATOR to correctly discern the
characteristics of ALARM SIGNALS. Usability is an important element in the design of ALARM
SIGNALS that are readily discernible without being unnecessarily distracting or disturbing. This
approach is intended to rationalize the current situation, to reduce confusion by limiting
proliferation of ALARM SIGNALS and their control states, and to minimize distraction for other
people. This collateral standard was developed with contributions from clinicians, engineers
and applied psychologists.
The terminology, requirements, general recommendations and guidance of this collateral
standard are intended to be useful for manufacturers of MEDICAL ELECTRICAL EQUIPMENT and
MEDICAL ELECTRICAL SYSTEMS and for technical committees responsible for particular
standards.
The effectiveness of any ALARM SYSTEM depends critically on its implementation by the USER.
It is important that the USER configure the ALARM SYSTEM so that an OPERATOR is not able to
compromise it.
___________
1)
Figures in brackets refer to the bibliography.
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60601-1-8 IEC:2003(E) – 7 –
MEDICAL ELECTRICAL EQUIPMENT –
Part 1-8: General requirements for safety –
Collateral Standard:
General requirements, tests and guidance for alarm systems
in medical electrical equipment and medical electrical systems
SECTION ONE – GENERAL
1 * Scope and object
1.201 Scope
This collateral standard specifies requirements for ALARM SYSTEMS and ALARM SIGNALS in
MEDICAL ELECTRICAL EQUIPMENT and MEDICAL ELECTRICAL SYSTEMS.
It also provides guidance for the application of ALARM SYSTEMS.
1.202 Object
The object of this collateral standard is to specify basic safety and essential performance
requirements and tests for ALARM SYSTEMS in MEDICAL ELECTRICAL EQUIPMENT and MEDICAL
ELECTRICAL SYSTEMS and to provide guidance for their application. This is accomplished by
defining alarm categories (priorities) by degree of urgency, consistent ALARM SIGNALS and
consistent control states and their marking for all ALARM SYSTEMS.
NOTE See IEC 60513:1994 [4] for a description of basic safety and essential performance.
This collateral standard does not specify:
– whether any particular MEDICAL ELECTRICAL EQUIPMENT or MEDICAL ELECTRICAL SYSTEM is
required to be provided with ALARM SYSTEMS;
– the particular circumstances which initiate an ALARM CONDITION;
– the allocation of priorities to a particular ALARM CONDITION; or
– the means of generating ALARM SIGNALS.
1.203 Relationship to other standards
1.203.1 IEC 60601-1
For MEDICAL ELECTRICAL EQUIPMENT, this collateral standard complements IEC 60601-1.
When referring to IEC 60601-1 or to this collateral standard, either individually or in
combination, the following conventions are used:
– "the general standard" designates IEC 60601-1 alone;
– "this collateral standard" designates IEC 60601-1-8 alone;
– "this standard" designates the combination of the general standard and this collateral
standard.
1.203.2 Particular standards
A requirement in a particular standard takes priority over the corresponding requirement in
this collateral standard.
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1.203.3 Normative references
The following referenced documents are indispensable for the application 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.
2)
IEC 60417-DB:2000-10 , Graphical symbols for use on equipment
IEC 60601-1:1988 Medical electrical equipment – Part 1: General requirements for safety
Amendment 1 (1991)
Amendment 2 (1995)
IEC 60601-1-1:2000, Medical electrical equipment – Part 1-1: General requirements for safety
– Collateral standard: Safety requirements for medical electrical systems
3)
IEC 60601-1-6:― , Medical electrical equipment – Part 1-6: General requirements for safety
– Collateral standard: Usability
4)
IEC 60651:1979 , Sound level meters
Amendment 1 (1993)
Amendment 2 (2000)
ISO 3744:1994, Acoustics – Determination of sound power levels of noise sources using
sound pressure – Engineering method in an essentially free field over a reflecting plane
ISO 7000:1989, Graphical symbols for use on equipment – Index and synopsis
2 Terminology and definitions
5)
For the purposes of this collateral standard, the following definitions apply.
NOTE This collateral standard uses the term “equipment” to mean MEDICAL ELECTRICAL EQUIPMENT or non-MEDICAL
ELECTRICAL EQUIPMENT in the context of a MEDICAL ELECTRICAL SYSTEM.
2.201
* ALARM CONDITION
state of the ALARM SYSTEM when it has determined that a potential or actual hazard exists
NOTE 1 An ALARM CONDITION can be invalid, i.e. a FALSE POSTIVE ALARM CONDITION.
NOTE 2 An ALARM CONDITION can be missed, i.e. a FALSE NEGATIVE ALARM CONDITION.
2.202
* ALARM CONDITION DELAY
time from the occurrence of a triggering event either in the PATIENT, for PHYSIOLOGICAL ALARM
CONDITIONS, or in the equipment, for TECHNICAL ALARM CONDITIONS, to when the ALARM SYSTEM
determines that an ALARM CONDITION exists
2.203
* ALARM LIMIT
threshold used by an ALARM SYSTEM to determine an ALARM CONDITION
___________
2)
“DB” refers to the IEC on-line database.
3)
To be published
4)
A consolidated edition (1.2) exists including IEC 60651 (1997) and its Amendment 1 (1993) and Amendment 2
(2000)
5)
An index of defined terms is found beginning on page 70.
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60601-1-8 IEC:2003(E) – 9 –
2.204
ALARM OFF
state of indefinite duration in which an ALARM SYSTEM or part of an ALARM SYSTEM does not
generate ALARM SIGNALS
2.205
* ALARM PAUSED
state of limited duration in which the ALARM SYSTEM or part of the ALARM SYSTEM does not
generate ALARM SIGNALS
2.206
ALARM PRESET
set of stored configuration parameters, including selection of algorithms and initial values for
use by algorithms, which affect or modify the performance of the ALARM SYSTEM
2.207
ALARM RESET
OPERATOR action that causes the cessation of an ALARM SIGNAL for which no associated ALARM
CONDITION currently exists
2.208
ALARM SETTINGS
ALARM SYSTEM configuration, including but not limited to:
– ALARM LIMITS;
– the characteristics of any ALARM SIGNAL inactivation states; and
– the values of variables or parameters that determine the function of the ALARM SYSTEM.
NOTE Some algorithmically determined ALARM SETTINGS can require time to be determined or re-determined.
2.209
ALARM SIGNAL
type of signal generated by the ALARM SYSTEM to indicate the presence (or occurrence) of an
ALARM CONDITION
2.210
* ALARM SIGNAL GENERATION DELAY
time from the onset of an ALARM CONDITION to the generation of its ALARM SIGNALS
2.211
ALARM SYSTEM
parts of MEDICAL ELECTRICAL EQUIPMENT or a MEDICAL ELECTRICAL SYSTEM that detect ALARM
CONDITIONS and, as appropriate, generate ALARM SIGNALS
2.212
AUDIO OFF
state of indefinite duration in which the ALARM SYSTEM or part of the ALARM SYSTEM does not
generate an auditory ALARM SIGNAL
2.213
AUDIO PAUSED
state of limited duration in which the ALARM SYSTEM or part of the ALARM SYSTEM does not
generate an auditory ALARM SIGNAL
2.214
BURST
group of PULSES with a distinctive rhythm or pattern
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2.215
DE-ESCALATION
process by which an ALARM SYSTEM decreases the priority of an ALARM CONDITION or decreases
the sense of urgency of an ALARM SIGNAL
2.216
DEFAULT ALARM PRESET
ALARM PRESET that can be activated by the ALARM SYSTEM without OPERATOR action
NOTE Manufacturer- or USER-configured ALARM PRESETS are possible types of DEFAULT ALARM PRESETS.
2.217
* DISTRIBUTED ALARM SYSTEM
ALARM SYSTEM that involves more than one item of equipment of a MEDICAL ELECTRICAL SYSTEM
NOTE The parts of a DISTRIBUTED ALARM SYSTEM can be widely separated in distance.
2.218
ESCALATION
process by which an ALARM SYSTEM increases the priority of an ALARM CONDITION or increases
the sense of urgency of an ALARM SIGNAL
2.219
FALL TIME
t
f
interval over which the PULSE amplitude decreases from 90 % to 10 % of its maximum (see
Figure 201)
2.220
FALSE NEGATIVE ALARM CONDITION
absence of an ALARM CONDITION when a valid triggering event has occurred in the PATIENT, the
equipment or the ALARM SYSTEM
NOTE An ALARM CONDITION can be rejected or missed because of spurious information produced by the PATIENT,
the PATIENT-equipment interface, other equipment or the equipment itself.
2.221
FALSE POSITIVE ALARM CONDITION
presence of an ALARM CONDITION when no valid triggering event has occurred in the PATIENT,
the equipment or the ALARM SYSTEM
NOTE A FALSE POSITIVE ALARM CONDITION can be caused by spurious information produced by the PATIENT, the
PATIENT-equipment interface, other equipment or the ALARM SYSTEM itself.
2.222
HIGH PRIORITY
indicating that immediate OPERATOR response is required
NOTE The priority is assigned through risk analysis.
2.223
* INFORMATION SIGNAL
any signal that is not an ALARM SIGNAL or a REMINDER SIGNAL
EXAMPLE 1 ECG waveform
EXAMPLE 2 SpO tone
2
EXAMPLE 3 Fluoroscopy beam-on indication
2.224
* INTELLIGENT ALARM SYSTEM
ALARM SYSTEM that makes logical decisions based on monitored information without OPERATOR
intervention
EXAMPLE 1 An ALARM SYSTEM that changes priority based on the rate of change of a monitored variable.
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60601-1-8 IEC:2003(E) – 11 –
EXAMPLE 2 An ALARM SYSTEM that suppresses an ALARM CONDITION when a related ALARM CONDITION of higher
priority has recently generated an ALARM SIGNAL.
2.225
INTERBURST INTERVAL
t
b
period of time between the end of the last PULSE of a BURST and the start of the first PULSE of
the next BURST of the same ALARM SIGNAL (see Figure 201)
2.226
LATCHING ALARM SIGNAL
ALARM SIGNAL that continues to be generated after its triggering event no longer exists until
stopped by deliberate OPERATOR action
2.227
LOW PRIORITY
indicating that OPERATOR awareness is r
...
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