EN IEC 60812:2018

SLOVENSKI STANDARD
01-december-2018
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Failure modes and effects analysis (FMEA and FMECA) (IEC 60812:2018)
Ta slovenski standard je istoveten z: EN IEC 60812:2018
ICS:
03.120.01 Kakovost na splošno Quality in general
21.020 =QDþLOQRVWLLQQDþUWRYDQMH Characteristics and design of
VWURMHYDSDUDWRYRSUHPH machines, apparatus,
equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60812

NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2018
ICS 03.120.01; 03.120.30; 21.020 Supersedes EN 60812:2006
English Version
Failure modes and effects analysis (FMEA and FMECA)
(IEC 60812:2018)
Analyse des modes de défaillance et de leurs effets (AMDE Ausfalleffektanalyse (FMEA und FMECA)
et AMDEC) (IEC 60812:2018)
(IEC 60812:2018)
This European Standard was approved by CENELEC on 2018-09-14. 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey 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
© 2018 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60812:2018 E
European foreword
The text of document 56/1775/FDIS, future edition 3 of IEC 60812, prepared by IEC/TC 56
"Dependability" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2019-06-14
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2021-09-14
document have to be withdrawn
This document supersedes EN 60812:2006.
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.
Endorsement notice
The text of the International Standard IEC 60812:2018 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 standards
indicated:
IEC 60300-1 NOTE Harmonized as EN 60300-1
IEC 60300-3-1 NOTE Harmonized as EN 60300-3-1
IEC 60300-3-12 NOTE Harmonized as EN 60300-3-12
IEC 60300-3-11 NOTE Harmonized as EN 60300-3-11
IEC 61025 NOTE Harmonized as EN 61025
IEC 61078 NOTE Harmonized as EN 61078
IEC 61165 NOTE Harmonized as EN 61165
IEC 61508 series NOTE Harmonized as EN 61508 series
IEC 61709 NOTE Harmonized as EN 61709
IEC 62061 NOTE Harmonized as EN 62061
IEC 62308 NOTE Harmonized as EN 62308
IEC 62502 NOTE Harmonized as EN 62502
IEC 62508 NOTE Harmonized as EN 62508
IEC 62551 NOTE Harmonized as EN 62551
IEC 62740 NOTE Harmonized as EN 62740
IEC 62741 NOTE Harmonized as EN 62741
ISO 9000 NOTE Harmonized as EN ISO 9000
ISO 13849-1 NOTE Harmonized as EN ISO 13849-1

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.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60050-192 -  International electrotechnical vocabulary - - -
Part 192: Dependability
IEC 60812 ®
Edition 3.0 2018-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Failure modes and effects analysis (FMEA and FMECA)

Analyse des modes de défaillance et de leurs effets (AMDE et AMDEC)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 03.120.01  03.120.30  21.020 ISBN 978-2-8322-5915-3

– 2 – IEC 60812:2018 © IEC 2018
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 9
3 Terms, definitions and abbreviated terms . 9
3.1 Terms and definitions . 9
3.2 Abbreviated terms . 13
4 Overview . 14
4.1 Purpose and objectives . 14
4.2 Roles, responsibilities and competences . 14
4.3 Terminology . 15
5 Methodology for FMEA . 15
5.1 General . 15
5.2 Plan the FMEA . 17
5.2.1 General . 17
5.2.2 Define the objectives and scope of analysis . 17
5.2.3 Identify boundaries and scenarios . 17
5.2.4 Define decision criteria for treatment of failure modes . 19
5.2.5 Determine documentation and reporting requirements . 20
5.2.6 Define resources for analysis . 21
5.3 Perform the FMEA . 22
5.3.1 General . 22
5.3.2 Sub-divide item or process into elements . 22
5.3.3 Identify functions and performance standards for each element . 23
5.3.4 Identify failure modes . 23
5.3.5 Identify detection methods and existing controls . 23
5.3.6 Identify local and final effects of failure modes . 24
5.3.7 Identify failure causes . 25
5.3.8 Evaluate relative importance of failure modes . 26
5.3.9 Identify actions . 28
5.4 Document the FMEA . 29
Annex A (informative) General considerations for tailoring an FMEA . 30
A.1 General . 30
A.1.1 Overview . 30
A.1.2 Start point for FMEA in the hierarchy . 30
A.1.3 Degree of detail in analysis . 31
A.1.4 Prioritization of failure modes . 32
A.2 Factors influencing FMEA tailoring . 33
A.2.1 Reuse of data/information from analysis of similar item . 33
A.2.2 Maturity of item design and project progress . 34
A.2.3 Degree of innovation . 34
A.3 Examples of FMEA tailoring for items and processes . 34
A.3.1 General . 34
A.3.2 Example of tailoring an FMEA for an office equipment product . 35
A.3.3 Example of tailoring an FMEA for a distributed power system . 35
A.3.4 Example of tailoring an FMEA for medical processes . 36

IEC 60812:2018 © IEC 2018 – 3 –
A.3.5 Example of tailoring an FMEA for electronic control systems . 36
A.3.6 Example of tailoring an FMEA for a pump hydro block . 37
A.3.7 Example of tailoring an FMEA for a wind turbine for power generation . 37
Annex B (informative) Criticality analysis methods . 38
B.1 General . 38
B.2 Measurement scales for criticality parameters . 38
B.2.1 General . 38
B.2.2 Scale definition . 38
B.2.3 Assessing likelihood . 39
B.3 Assigning criticality using a matrix or plot . 40
B.3.1 General . 40
B.3.2 Criticality matrix . 40
B.3.3 Criticality plots . 41
B.4 Assigning criticality using a risk priority number . 42
B.4.1 General . 42
B.4.2 Risk priority number . 42
B.4.3 Alternative risk priority number method . 44
Annex C (informative) Example of FMEA report content . 46
C.1 General . 46
C.2 Example of generation of reports from a database information system for an
FMEA of a power supply unit . 46
Annex D (informative) Relationship between FMEA and other dependability analysis
techniques . 52
Annex E (informative) Application considerations for FMEA . 53
E.1 General . 53
E.2 Software FMEA . 53
E.3 Process FMEA . 55
E.4 FMEA for design and development . 56
E.5 FMEA within reliability centred maintenance . 56
E.6 FMEA for safety related control systems . 56
E.6.1 General . 56
E.6.2 FMEA in planning a safety application . 57
E.6.3 Criticality analysis including diagnostics . 57
E.7 FMEA for complex systems with reliability allocation . 58
E.7.1 General . 58
E.7.2 Criticality assessment for non-repairable systems with allocated
unreliability . 58
E.7.3 Criticality assessment for repairable systems with allocated availability . 59
Annex F (informative) Examples of FMEA from industry applications . 60
F.1 General . 60
F.2 Health process application for drug ordering process . 60
F.3 Manufacturing process application for paint spraying . 60
F.4 Design application for a water pump . 61
F.4.1 General . 61
F.4.2 Item function . 61
F.4.3 Item failure modes . 61
F.4.4 Item failure effects . 61
F.5 Example of an FMEA with criticality analysis for a complex non-repaired
system . 62

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F.6 Software application for a blood sugar calculator . 63
F.7 Automotive electronics device . 63
F.8 Maintenance and support application for a hi-fi system . 64
F.9 Safety related control system applications . 65
F.9.1 Electronic circuit . 65
F.9.2 Automated train control system . 65
F.10 FMEA including human factors analysis . 65
F.11 Marking and encapsulation process for an electronic component . 66
Bibliography . 76

Figure 1 – Overview of FMEA methodology before tailoring . 16
Figure B.1 – Example of a qualitative criticality matrix . 40
Figure B.2 – Examples of criticality plots . 41
Figure C.1 – Database information system to support FMEA report generation . 47
Figure C.2 – Diagram of power supply type XYZ . 47
Figure C.3 – Criticality matrix for FMECA report in Table C.5 created as a two
dimensional image without taking into account detectability . 51
Figure E.1 – General software failure model for a component software unit (CSU) . 55
Figure E.2 – Allocation of system failure probabilities . 59
Figure F.1 – Hierarchy of a series electronic system, its subsystems and assemblies
with allocated unreliability values, F(t) . 62
Figure F.2 – Automotive air-bag part . 64

Table 1 – Example of terms commonly associated with levels of hierarchy. 15
Table A.1 – Characteristics of top-down and bottom-up approaches to FMEA . 31
Table A.2 – General application of common approaches to FMEA . 33
Table C.1 – Example of fields selected for FMEA report of power supply based on

database information . 48
Table C.2 – Example of report of component FMEA . 49
Table C.3 – Example of report of parts with possible common cause failures . 50
Table C.4 – Example of report of FMECA using RPN criticality analysis . 50
Table C.5 – Example of report of FMECA using criticality matrix for global effect . 51
Table F.1 – Extract from FMEA of the process of ordering a drug from a pharmacy . 60
Table F.2 – Extract from FMEA of paint spraying step of a manufacturing process . 61
Table F.3 – Allocation and assessment of unreliability values for different criticality
categories of failure modes for the electronic system represented in Figure F.1 . 63
Table F.4 – Allocation and assessment of unreliability values for different criticality
categories of failure modes for subsystem 2 of the system represented in Figure F.1 . 63
Table F.5 – Hazards and safe/dangerous failures in an automated train control system . 65
Table F.6 – Extract from FMEA of the process of monitoring blood sugar (1 of 2) . 67
Table F.7 – Extract of automotive electronic part FMEA . 69
Table F.8 – Extract from system FMEA for a remote control for a hi-fi system . 70
Table F.9 – Extract from design FMEA for a remote control for a hi-fi system . 70
Table F.10 – Extract from process FMEA for a remote control for a hi-fi system . 71
Table F.11 – Extract from maintenance service FMEA for a remote control for a hi-fi

system . 71

IEC 60812:2018 © IEC 2018 – 5 –
Table F.12 – Extract from an FMEDA for an electronic circuit in a safety control system
(1 of 2) . 72
Table F.13 – Extract from an FMEA for a coffee-maker . 74
Table F.14 – Extract from an FMEA for an electronic component marking and
encapsulation process . 75

– 6 – IEC 60812:2018 © IEC 2018
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FAILURE MODES AND EFFECTS ANALYSIS (FMEA and FMECA)

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,
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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 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 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) 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 60812 has been prepared by IEC technical committee 56:
Dependability.
This third edition cancels and replaces the second edition published in 2006. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the normative text is generic and covers all applications;
b) examples of applications for safety, automotive, software and (service) processes have
been added as informative annexes;
c) tailoring the FMEA for different applications is described;
d) different reporting formats are described, including a database information system;
e) alternative means of calculating risk priority numbers (RPN) have been added;
f) a criticality matrix based method has been added;
g) the relationship to other dependability analysis methods have been described.

IEC 60812:2018 © IEC 2018 – 7 –
The text of this International Standard is based on the following documents:
FDIS Report on voting
56/1775/FDIS 56/1782/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 8 – IEC 60812:2018 © IEC 2018
INTRODUCTION
Failure modes and effects analysis (FMEA) is a systematic method of evaluating an item or
process to identify the ways in which it might potentially fail, and the effects of the mode of
failure upon the performance of the item or process and on the surrounding environment and
personnel. This document describes how to perform an FMEA.
The purpose of performing an FMEA is to support decisions that reduce the likelihood of
failures and their effects, and thus contribute to improved outcomes either directly or through
other analyses. Such improved outcomes include, but are not limited to, improved reliability,
reduced environmental impact, reduced procurement and operating costs, and enhanced
business reputation.
FMEA can be adapted to meet the needs of any industry or organization. FMEA is applicable
to hardware, software, processes, human action and their interfaces, in any combination.
FMEA can be carried out several times in the lifetime for the same item or process. A
preliminary analysis can be conducted during the early stages of design and planning,
followed by a more detailed analysis when more information is available. FMEA can include
existing controls, or recommended treatments, to reduce the likelihood or the effects of a
failure mode. In the case of a closed loop analysis, FMEA allows for evaluation of the
effectiveness of any treatment.
FMEA can be tailored and applied in different ways depending on the objectives.
Failure modes may be prioritized according to their importance. The prioritization can be
based on a ranking of the severity alone, or this can be combined with other measures of
importance. When failure modes are prioritized, the process is referred to as failure modes,
effects and criticality analysis (FMECA). This document uses the term FMEA to include
FMECA.
This document gives general guidance on how to plan, perform, document and maintain an
FMEA by:
a) describing the principles;
b) providing the steps in analysis;
c) giving examples of the documentation;
d) providing example applications.
FMEA may be used in a certification or assurance process. For example, FMEA may be used
in safety analysis for regulatory purposes but, as this document is a generic standard, it does
not specifically address safety.
FMEA should be conducted in a manner that is consistent with any legislation, which is in
effect within the scope of FMEA, or the type of risks involved.
Primary users of this document are those who are leading or participating in the analysis.

IEC 60812:2018 © IEC 2018 – 9 –
FAILURE MODES AND EFFECTS ANALYSIS (FMEA and FMECA)

1 Scope
This document explains how failure modes and effects analysis (FMEA), including the failure
modes, effects and criticality analysis (FMECA) variant, is planned, performed, documented
and maintained.
The purpose of failure modes and effects analysis (FMEA) is to establish how items or
processes might fail to perform their function so that any required treatments could be
identified. An FMEA provides a systematic method for identifying modes of failure together
with their effects on the item or process, both locally and globally. It may also include
identifying the causes of failure modes. Failure modes can be prioritized to support decisions
about treatment. Where the ranking of criticality involves at least the severity of
consequences, and often other measures of importance, the analysis is known as failure
modes, effects and criticality analysis (FMECA).
This document is applicable to hardware, software, processes including human action, and
their interfaces, in any combination.
An FMEA can be used in a safety analysis, for regulatory and other purposes, but this being a
generic standard, does not give specific guidance for safety applications.
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 60050-192, International electrotechnical vocabulary – Part 192: Dependability (available
at http://www.electropedia.org)
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purpose of this document, the terms and definitions given in IEC 60050-192 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
failure mode
DEPRECATED: fault mode
manner in which failure occurs
Note 1 to entry: A failure mode may be determined by the function lost or other state transition that occurred.

– 10 – IEC 60812:2018 © IEC 2018
Note 2 to entry: Examples of hardware failure modes might be for a valve, "does not open", or for an engine,
"does not start".
Note 3 to entry: A human failure mode is determined by the function lost as a result of human action, whether
committed or omitted.
[SOURCE: IEC 60050-192:2015, 192-03-17, modified — Note 1 has been modified, Note 2
and Note 3 have been added.]
3.1.2
failure effect
consequence of a failure, within or beyond the boundary of the failed item
Note 1 to entry: For some analyses, it may be necessary to consider individual failure modes and their effects.
Note 2 to entry: Failure effect also covers the consequence of a failure, within or beyond the boundary of the
failed process.
[SOURCE: IEC 60050-192:2015, 192-03-08, modified — Note 2 has been added.]
3.1.3
system
combination of interacting elements organized to achieve one or more stated purposes
Note 1 to entry: A system is sometimes considered as a product or as the services it provides.
Note 2 to entry: In practice, the interpretation of its meaning is frequently clarified by the use of an associative
noun, e.g., aircraft system. Alternatively, the word “system” is substituted simply by a context-dependent synonym,
e.g., aircraft, though this potentially obscures a system principles perspective.
[SOURCE: ISO/IEC/IEEE 15288:2015, 4.1.46, modified — Note 3 has been deleted.]
3.1.4
item
subject being considered
Note 1 to entry: The item may be an individual part, component, device, functional unit, equipment, subsystem, or
system.
Note 2 to entry: The item may consist of hardware, software, people or any combination thereof.
Note 3 to entry: The item is often comprised of elements that may each be individually considered.
Note 4 to entry: IEC 60050-191:1990 (now withdrawn; replaced by IEC 60050-192:2015) identified the term “entity”
as an English synonym, which is not true for all applications.
Note 5 to entry: The definition for item in IEC 60050-191:1990 (now withdrawn; replaced by IEC 60050-192:2015)
is a description rather than a definition. This new definition provides meaningful substitution throughout this
document. The words of the former definition form new note 1.
[SOURCE: IEC 60050-192:2015, 192-01-01]
3.1.5
process
set of interrelated or interacting activities that transforms inputs into outputs
[SOURCE: IEC 60050-192:2015, 192-01-08]
3.1.6
hierarchy level
level of sub-division within a system, item or process hierarchy
Note 1 to entry: Hierarchy level may also be known as the indenture level [see IEC 60050-192:2015, 192-01-05].

IEC 60812:2018 © IEC 2018 – 11 –
Note 2 to entry: Top-level and low-level corresponds to the highest and lowest levels of the hierarchy,
respectively. Mid-level corresponds to levels between the highest and lowest levels.
3.1.7
element
level of sub-division of a system, item or process hierarchy at which failure modes are to be
identified
3.1.8
scenario
possible sequence of specified conditions under which the system, item or process functions
are performed
Note 1 to entry: Conditions may include activities or factors outside the defined item or process boundaries under
study which may affect the performance of the item or process.
Note 2 to entry: Physical conditions include all environmental factors such as temperature, humidity, light levels,
shock, contamination, radiation levels.
Note 3 to entry: Organizational conditions include factors such as staffing levels, physical/psychological stresses.
3.1.9
failure cause
set of circumstances that leads to failure
Note 1 to entry: A failure cause may originate during specification, design, manufacture, installation, operation or
maintenance of an item.
Note 2 to entry: Examples of a failure cause may be contamination or inadequate lubrication which leads to the
failure mode of bearing seizure.
Note 3 to entry: Failure causes for a process might include human error mechanisms such as stimulus overload,
memory failure, misunderstanding, false assumption.
[SOURCE: IEC 60050-192:2015, 192-03-11, modified — Note 2 and Note 3 have been added.]
3.1.10
failure mechanism
process that leads to failure
Note 1 to entry: The process may be physical, chemical, logical, psychological or a combination thereof.
[SOURCE: IEC 60050-192:2015, 192-03-12, modified — Note 1 has been reworded.]
3.1.11
likelihood
chance of something happening
Note 1 to entry: In this document, the term “likelihood” is used to refer to the chance of something happening,
whether defined, measured or determined objectively or subjectively, qualitatively or quantitatively, and described
using general terms or mathematically [such as probability or a frequency over a given time period].
Note 2 to entry: The English term “likelihood” does not have a direct equivalent in some languages; instead, the
equivalent of the term “probability” is often used. However, in English, “probability” is often narrowly interpreted as
a mathematical term. Therefore, in terminology used in this document, the term “likelihood” is used with the intent
that it should have the same broad interpretation as the term “probability” has in many languages other than
English.
[SOURCE: ISO Guide 73:2009, 3.6.1.1, modified — Note 1 and Note 2 have been reworded.]
3.1.12
severity
relative ranking of potential or actual consequences of a failure or a fault
Note 1 to entry: The severity may be related to any consequence.

– 12 – IEC 60812:2018 © IEC 2018
[SOURCE: EN 13306:2010, 5.13, modified — “relative ranking” has been added.]
3.1.13
detection method
means by which a failure mode or incipient failure become evident
3.1.14
control
design features, or other existing provisions, that have the ability to prevent or reduce the
likelihood of the failure mode or modify its effect
Note 1 to entry: Controls can also be referred to as compensating provisions.
3.1.15
criticality
importance ranking determined using a specified evaluation criteria
Note 1 to entry: The criticality evaluation criteria normally refer to the effects of the failure mode on the top-level
in the system, item or process hierarchy.
Note 2 to entry: Criticality measures normally combine severity of effect with at least one other characteristic of a
failure mode.
Note 3 to entry: The specific meaning of criticality is dependent upon the evaluation method defined within an
analysis and is discussed in detail within this document.
Note 4 to entry: Criticality relates to the failure mode and not to the failure causes (if the latter are identified at
all).
3.1.16
treatment
action to modify the likelihood and/or effects of a failure mode
Note 1 to entry: Treatment is sometimes referred to as mitigation.
Note 2 to entry: Treatment may involve actions to eliminate the failure cause, change the likelihood of the failure
mode occurring, and/or change the consequences.
3.1.17
human error
discrepancy between the human action taken or omitted, and that intended or required
EXAMPLE Performing an incorrect action; omitting a required action; miscalculation; misreading a value.
[SOURCE: IEC 60050-192:2015, 192-03-14]
3.1.18
redundancy
provision of more than one means for performing a function
Note 1 to entry: The additional means of performing the function can be intentionally different (diverse) to reduce
the potential for common mode failures.
[SOURCE: IEC 60050-192:2015, 192-10-02]
3.1.19
common cause failures
failures of multiple items, which would otherwise be considered independent of one another
resulting from a single cause
Note 1 to entry: Common cause failures can also be "common mode failures".
Note 2 to entry: The potential for common cause failures reduces the effectiveness of system redundancy.

IEC 60812:2018 © IEC 2018 – 13 –
[SOURCE: IEC 60050-192:2015, 192-03-18]
3.1.20
common mode failures
failures of different items characterized by the same failure mode
Note 1 to entry: Common mode failures can have different causes.
Note 2 to entry: Common mode failures can also be “common cause failures”.
Note 3 to entry: The potential for common mode failures reduces the effectiveness of system redundancy.
[SOURCE: IEC 60050-192:2015, 192-03-19]
3.1.21
testability
degree to which an item can be tested, during and after operation to detect and
isolate failures/faults
[SOURCE: IEC 60050-192:2015, 192-09-20, modified — "during and after operation to detect
and isolate failures/faults" has been added.]
3.2 Abbreviated terms
ARPN alternative risk priority number
CCF common cause failure
COTS commercial off the shelf
CSU component software unit
DC diagnostic coverage
EMI electromagnetic interference
EMP electromagnetic pulse
ESD emergency shutdown
ETA event tree analysis
FIT failure in time
FTA fault tree analysis
FMEA failure modes and effects analysis
FMECA failure modes, effects and criticality analysis
FMEDA failure modes, effects and diagnostic analysis
MTBF mean operating time between failures
MTTR mean time to restoration
OEM original equipment manufacturer
RBD reliability block diagram
RCM reliability centred maintenance
RPN risk priority number
SFF safe failure fraction
SIL safety integrity level
SOD severity, occurrence and detectability

– 14 – IEC 60812:2018 © IEC 2018
4 Overview
4.1 Purpose and objectives
An FMEA is a method in which an item or a process is broken down into elements and, for
each element in turn, failure modes and effects are identified and analysed. This is to identify
any required improvements by eliminating adverse effects or reducing their likelihood or
severity. The purpose of adding a criticality analysis is to enable prioritization of the failure
modes for potential treatment.
The reasons for which FMEA is undertaken include the following:
• to identify those failure modes which have unwanted effects on system operation, for
example preclude or significantly degrade operation or affect the safety of the user and
other persons;
• to improve the design and development of items or processes in a cost effective manner
by intervening early in the development programme;
• to identify risks as part of a risk management process (ISO 31000);
• to satisfy statutory and business obligations by demonstrating that foreseeable risks have
been identified and accounted for;
• to provide a foundation for other dependability analyses (Annex D discusses the
relationship between FMEA and other dependability analysis methods);
• to develop and support a reliability test programme;
• to provide a basis for planning maintenance and support prog
...