IEC 60300-1:2024

Dependability management - Part 1: Managing dependability

IEC 60300-1:2024 provides guidance on:
- the meaning and significance of dependability from a business, technical and financial perspective;
- achieving dependability through suitable adaptation of organizational management systems such as those described in ISO 9001 (quality management) and ISO 55001 (asset management);
- the activities that are integrated into management systems and life cycle processes in order to achieve dependable systems, products and services;
- planning and implementing dependability activities throughout the life cycle to achieve and assure required outcomes, taking into account factors such as costs, safety, the environment, customer goodwill, brand and reputation.
This document is applicable to any type of system, both new and existing, to mass produced industrial or consumer products, to components and to services. This document addresses all elements of systems, products and services including hardware, software, data, processes, procedures, facilities, materials, and personnel required for operations and support.

Gestion de la sûreté de fonctionnement - Partie 1: Gérer la sureté de fonctionnement

L'IEC 60300-1:2024 fournit des recommandations sur:
- la signification et l’importance de la sûreté de fonctionnement du point de vue commercial, technique et financier;
- l’obtention de la sûreté de fonctionnement par une adaptation appropriée des systèmes de management organisationnel, tels que ceux décrits dans la série ISO 9001 (management de la qualité) et dans la série ISO 55001 (gestion d’actifs);
- les activités qui sont intégrées dans les systèmes de management et les processus du cycle de vie afin d’obtenir des systèmes, produits et services fiables;
- la planification et la mise en œuvre d’activités de sûreté de fonctionnement tout au long du cycle de vie afin d’obtenir et d’assurer les résultats exigés, en tenant compte de facteurs tels que les coûts, la sécurité, l’environnement, la clientèle, la marque et la réputation.
Le présent document est applicable à tout type de système, neuf et existant, aux produits industriels ou de consommation fabriqués en série, aux composants et aux services. Le présent document traite de tous les éléments des systèmes, produits et services, y compris le matériel, les logiciels, les données, les processus, les procédures, les installations, les matériaux et le personnel exigé pour les opérations et le soutien.

General Information

• Status: Published
• Publication Date: 10-Jun-2024
• ICS: 03.100.40 - Research and development
• ICS: 03.120.01 - Quality in general
• ICS: 21.020 - Characteristics and design of machines, apparatus, equipment
• Technical Committee: TC 56 - Dependability
• Drafting Committee: MT 25 - TC 56/MT 25
• Current Stage: PPUB - Publication issued
• Start Date: 11-Jun-2024
• Completion Date: 22-Mar-2024

Relations

• Revises: IEC 60300-1:2014 - Dependability management - Part 1: Guidance for management and application
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60300-1 ®
Edition 4.0 2024-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Dependability management –
Part 1: Managing dependability

Gestion de la sûreté de fonctionnement –
Partie 1: Gérer la sureté de fonctionnement
All rights reserved. Unless otherwise specified, 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
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite ni
utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et
les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.

IEC Secretariat Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews, graphical symbols and the glossary.
committee, …). It also gives information on projects, replaced With a subscription you will always have access to up to date
and withdrawn publications. content tailored to your needs.

IEC Just Published - webstore.iec.ch/justpublished
Electropedia - www.electropedia.org
Stay up to date on all new IEC publications. Just Published
The world's leading online dictionary on electrotechnology,
details all new publications released. Available online and once
containing more than 22 500 terminological entries in English
a month by email.
and French, with equivalent terms in 25 additional languages.

Also known as the International Electrotechnical Vocabulary
IEC Customer Service Centre - webstore.iec.ch/csc
(IEV) online.
If you wish to give us your feedback on this publication or need

further assistance, please contact the Customer Service
Centre: [e-mail].
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.

Recherche de publications IEC -  IEC Products & Services Portal - products.iec.ch
webstore.iec.ch/advsearchform Découvrez notre puissant moteur de recherche et consultez
La recherche avancée permet de trouver des publications IEC gratuitement tous les aperçus des publications, symboles
en utilisant différents critères (numéro de référence, texte, graphiques et le glossaire. Avec un abonnement, vous aurez
comité d’études, …). Elle donne aussi des informations sur les toujours accès à un contenu à jour adapté à vos besoins.
projets et les publications remplacées ou retirées.

Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
Le premier dictionnaire d'électrotechnologie en ligne au monde,
Restez informé sur les nouvelles publications IEC. Just
avec plus de 22 500 articles terminologiques en anglais et en
Published détaille les nouvelles publications parues.
français, ainsi que les termes équivalents dans 25 langues
Disponible en ligne et une fois par mois par email.
additionnelles. Egalement appelé Vocabulaire

Electrotechnique International (IEV) en ligne.
Service Clients - webstore.iec.ch/csc

Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-nous:
[e-mail].
IEC 60300-1 ®
Edition 4.0 2024-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Dependability management –
Part 1: Managing dependability

Gestion de la sûreté de fonctionnement –

Partie 1: Gérer la sureté de fonctionnement

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 03.100.40, 03.120.01, 21.020 ISBN 978-2-8322-8320-2

– 2 – IEC 60300-1:2024 © IEC 2024
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions, and abbreviated terms . 8
3.1 Terms and definitions . 9
3.2 Abbreviated terms . 14
4 Key concepts and application of this document . 14
4.1 Overview. 14
4.2 Principles of dependability management . 14
4.3 Benefits of managing dependability . 15
4.4 Attributes of dependability . 16
4.5 Relationship between an organization's management system and
dependability . 18
4.6 Technical programmes for dependability . 19
4.7 Life cycle concept . 20
4.8 Dependability activity concept . 21
5 Integrating dependability into an organization's management system . 21
5.1 Overview. 21
5.2 Understanding the organization and its context . 22
5.3 Leadership . 22
5.4 Planning . 23
5.5 Support . 23
5.6 Documented information . 24
5.7 Operation . 25
5.8 Performance evaluation and improvement. 25
6 Programme design . 26
6.1 General . 26
6.2 Coordination and integration . 26
6.3 Trade-offs . 27
6.4 Tailoring a technical programme of dependability activities . 27
6.5 Key success factors . 28
7 Programme management activities . 28
7.1 Overview. 28
7.2 Plan dependability activities . 29
7.2.1 Purpose . 29
7.2.2 Outcomes . 29
7.2.3 Tasks . 29
7.3 Implement the plan . 31
7.3.1 Purpose . 31
7.3.2 Outcomes . 31
7.3.3 Tasks . 31
7.4 Review and improve . 32
7.4.1 Purpose . 32
7.4.2 Outcomes . 32
7.4.3 Tasks . 32

7.5 Providing assurance . 33
7.5.1 Purpose . 33
7.5.2 Outcomes . 33
7.5.3 Tasks . 33
7.6 Achieving accountability . 34
7.6.1 Purpose . 34
7.6.2 Outcomes . 34
7.6.3 Tasks . 34
8 Technical dependability activities. 35
8.1 Overview. 35
8.2 Stakeholder engagement, consensus building and communication . 35
8.2.1 Purpose . 35
8.2.2 Outcomes . 36
8.2.3 Tasks . 36
8.3 Managing opportunities, threats and risks . 37
8.3.1 Purpose . 37
8.3.2 Outcomes . 37
8.3.3 Tasks . 38
8.4 Dependability analysis . 38
8.4.1 Purpose . 38
8.4.2 Outcomes . 39
8.4.3 Tasks . 39
8.5 Dependability assessment . 40
8.5.1 Purpose . 40
8.5.2 Outcomes . 40
8.5.3 Tasks . 41
8.6 Maintenance, support and improvement . 41
8.6.1 Purpose . 41
8.6.2 Outcomes . 42
8.6.3 Tasks . 42
Annex A (informative) IEC standards related to dependability . 44
Annex B (informative) Life cycle models. 47
B.1 Generic life cycle . 47
B.2 Alternative life cycle models . 48
B.2.1 Life cycle model with multiple progressions . 48
B.2.2 Managing change through the life cycle . 48
B.2.3 Hardware . 49
B.2.4 Software (see Figure B.5) . 49
B.2.5 Services . 50
B.2.6 Open systems . 50
Annex C (informative) Stakeholders . 51
C.1 General . 51
C.2 Users of systems, products and services . 51
C.3 Managers . 51
C.4 The workforce . 51
C.5 Specialists . 52
C.6 Others. 52
C.7 Stakeholders through the life cycle . 52

– 4 – IEC 60300-1:2024 © IEC 2024
C.7.1 Concept – Specification . 52
C.7.2 Development . 52
C.7.3 Realization (including manufacture, transport acquisition and
installation) . 52
C.7.4 Operation or use of items . 53
C.7.5 Maintenance . 53
C.7.6 Obsolescence, retirement and re-use . 53
Annex D (informative) Dependability maturity assessment . 54
Annex E (informative) Dependability through the life cycle . 57
Annex F (informative) Comparison of approach of ISO/IEC/IEEE 15288 with that of
IEC 60300-1 . 60
F.1 Overview. 60
F.2 Concept of system life cycle processes . 60
Annex G (informative) Testing. 64
G.1 General . 64
G.2 Purpose and objectives of tests . 64
G.3 Test conditions . 64
G.4 Types of test . 65
G.5 Data quality and quantity . 66
Bibliography . 68

Figure 1 – Dependability and security attributes . 18
Figure 2 – Relationship between management system standards and dependability
standards . 19
Figure 3 – Integration of dependability into a management system . 22
Figure B.1 – Generic life cycle model . 47
Figure B.2 – Life cycle model with some of the possible progressions . 48
Figure B.3 – Managing change through the life cycle . 49
Figure B.4 – Example of hardware life cycle model . 49
Figure B.5 – Example of software life cycle model . 50
Figure B.6 – Example of service life cycle model . 50
Figure B.7 – Simplified life cycle model for an open system . 50
Figure F.1 – System life cycle processes according to ISO/IEC/IEEE 15288 . 61
Figure G.1 – Verification and validation methods or practices . 65

Table A.1 – Classification of dependability standards by topic and life cycle stage . 44
Table B.1 – Stages of generic model, their purpose and outputs . 47
Table D.1 – Example of dependability maturity matrix . 54
Table E.1 – Examples of dependability focus relevant to each life cycle stage . 57
Table F.1 – Comparison of approach of ISO/IEC/IEEE 15288 and IEC 60300-1 . 62

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DEPENDABILITY MANAGEMENT –
Part 1: Managing dependability

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,
Publicly Available Specifications (PAS) 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 itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 60300-1 has been prepared by IEC technical committee 56: Dependability. It is an
International Standard.
This fourth edition cancels and replaces the third edition published in 2014. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) more guidance on integration of dependability activities into an existing management
system;
b) greater detail on the activities required to establish and implement a programme of
dependability activities;
c) changes to provide consistency with other dependability standards.

– 6 – IEC 60300-1:2024 © IEC 2024
The text of this International Standard is based on the following documents:
Draft Report on voting
56/2031/FDIS 56/2044/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 60300 series, published under the general title Dependability
management, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
IMPORTANT – The "colour inside" logo on the cover page of this document 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.

INTRODUCTION
Dependability is the ability to perform as and when required. A dependable item is one where
there is justified confidence that it operates as desired and satisfies agreed stakeholder needs
and expectations. Dependability has many attributes but is usually characterised in terms of
reliability, maintainability and supportability, and the resulting availability. In some cases,
attributes such as resilience, recoverability, durability, integrity, safety, security, and
trustworthiness are included in, or overlap with, dependability.
The specification and verification of dependability attributes provide stakeholders with
assurance that requirements will be met into the future and quality will be maintained over time.
The dependability of a system, product or service influences the business strategies associated
with its design, acquisition and use, and costs over its life cycle. The dependability of an
organization's systems, products and services has a strong impact on the perception of the
value and trustworthiness of the organization.
Dependability is managed as a key element of an organization's wider management system,
particularly aspects relating to assets, quality and finance.
This document highlights the importance and benefits of managing dependability. It gives
guidance on dependability activities and their integration into an existing management system
and life cycle processes so that an efficient, effective and economical approach is achieved.
Dependability activities bring benefits whenever they are performed but greater benefit is
achieved the sooner in the life cycle they are implemented.
This document is applicable to a broad range of industry sectors and organizations of any size.
It applies to systems of systems, large unique systems, mass produced industrial and consumer
products, software applications, components and services. These categories are not mutually
exclusive. For example, many products and components are in themselves complex systems.
The document will be useful for:
• managers and technical personnel;
• those involved in deciding how their systems, products and services can be made
dependable;
• organizations such as regulators who evaluate the dependability of systems, products and
services;
• those (e.g. users or the public) who need justified confidence in systems, product and
services that might affect them;
• developers of other dependability related standards.
This document is one of a suite of "top level" interrelated IEC dependability standards that
provide managers and technical personnel with guidance on how to effectively plan and
implement dependability activities. Other documents in the suite are:
– IEC 60300-3-4 which provides guidance on writing dependability requirements in
specifications, and on the means of assuring the achievement of those requirements;
– IEC 60300-3-10 and IEC 60300-3-14 which provide guidance on how to identify and apply
appropriate analysis and assurance techniques for maintainability (and maintenance) and
supportability (and support) respectively;
– standards to cover reliability and availability, which are planned.

– 8 – IEC 60300-1:2024 © IEC 2024
DEPENDABILITY MANAGEMENT –
Part 1: Managing dependability

1 Scope
This document provides guidance on:
• the meaning and significance of dependability from a business, technical and financial
perspective;
• achieving dependability through suitable adaptation of organizational management systems
such as those described in ISO 9001 (quality management) and ISO 55001 (asset
management);
• the activities that are integrated into management systems and life cycle processes in order
to achieve dependable systems, products and services;
• planning and implementing dependability activities throughout the life cycle to achieve and
assure required outcomes, taking into account factors such as costs, safety, the
environment, customer goodwill, brand and reputation.
This document is applicable to any type of system, both new and existing, to mass produced
industrial or consumer products, to components and to services. This document addresses all
elements of systems, products and services including hardware, software, data, processes,
procedures, facilities, materials, and personnel required for operations and support.
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 60050-192:2015, International Electrotechnical Vocabulary (IEV) – Part 192: Dependability
(available at www.electropedia.org)
3 Terms, definitions, and abbreviated terms
For the purposes 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 Terms and definitions
3.1.1
accountability
state of being answerable for decisions and activities to the organization's governing bodies,
legal authorities and, more broadly, its stakeholders and society in general
Note 1 to entry: Accountability involves an obligation on management, the organization and individuals to be
answerable for the impact of their decisions and activities on stakeholders, society and the environment.
Accountability thus implies answerability to those affected and to society in general.
Note 2 to entry: Accountability implies that individuals, organizations and the community are responsible for their
actions and can be required to justify them to others.
[SOURCE: ISO 26000:2010, 2.1, modified – "and society in general" has been added to the
definition and notes to entry have been added.]
3.1.2
adaptability
ability to adjust to changed conditions or to be modified for a particular purpose or for a changed
environment
3.1.3
assurance
grounds for justified confidence that a claim has been or will be achieved
[SOURCE: ISO/IEC/IEEE 15026-1:2019, 3.1.1]
3.1.4
availability
ability to be in a state to perform as required under given conditions
Note 1 to entry: Availability depends upon the combined attributes of the reliability, maintainability, supportability
and on the maintenance and support provided.
Note 2 to entry: Availability can also be affected by delays before it is recognised that maintenance or support are
needed, for example fault detection time (192-06-18) and administrative delay (192-07-12).
Note 3 to entry: Given conditions include aspects that affect availability such as mode of operation, stress levels,
environmental conditions and maintenance defined in the life profile.
Note 4 to entry: Availability may be quantified using measures defined in IEC 60050-192:2015, 192-08, Availability
related measures.
[SOURCE: IEC 60050-192:2015, 192-01-23, modified – in the definition "of an item" has been
deleted, "under given conditions" has been added, Note 1 to entry has been modified, and Notes
2 and 3 to entry have been added.]
3.1.5
business process
partially ordered set of inter-related enterprise activities that can be executed to achieve some
desired end-result in pursuit of a given objective of an organization
Note 1 to entry: Business is interpreted broadly to mean those activities that are core to the purposes of the
organization's existence whether the organization is public, private, for profit or not for profit.
[SOURCE: ISO/IEC/IEEE 24765:2017, 3.445, modified – Note 1 to entry has been added.]

– 10 – IEC 60300-1:2024 © IEC 2024
3.1.6
dependability
ability to perform as and when required
Note 1 to entry: A dependable item or service is one where there is justified confidence that it operates as desired
and satisfies agreed stakeholder expectations.
Note 2 to entry: In most cases, the term dependability is used as an umbrella term to express its core attributes of
reliability, maintainability, and supportability and the resulting availability. In some cases, attributes such as
resilience, recoverability, durability, integrity, safety, security and trustworthiness are included in or overlap with
dependability.
Note 3 to entry: In order to express the ability to perform, requirements in terms of functions to be performed, when
the performance is to be achieved, and the life profile conditions, are specified by the customers, users or
stakeholders.
Note 4 to entry: The attributes of dependability can be expressed qualitatively or quantitatively.
Note 5 to entry: It is also a common practice to use the term dependability in the context of a subject of study or
discipline.
[SOURCE: IEC 60050-192:2015, 192-01-22, modified – "of an item" has been deleted, the notes
have been deleted and new notes to entry have been added.]
3.1.7
dependability activity
set of cohesive tasks carried out to achieve a dependability related purpose
Note 1 to entry: A dependability activity can be mapped to a process view that uses a combination of life cycle
processes, activities and tasks as defined in ISO/IEC/IEEE 15288.
3.1.8
dependability case
evidence-based, reasoned, traceable argument created to support the contention that a defined
system does and/or will satisfy the dependability requirements
Note 1 to entry: A dependability case is an assurance case for dependability-related claims, see
ISO/IEC/IEEE 15026-2.
[SOURCE: IEC 62741:2015, 3.1.1, modified – Note 1 to entry has been added.]
3.1.9
dependability plan
information item that presents a systematic course of action for achieving a declared purpose
related to dependability including when, how and by whom specific tasks are to be performed
3.1.10
durability
ability to perform as required, under defined conditions of use and maintenance until a defined
end state is reached
Note 1 to entry: The degree to which maintenance and repair are within the scope of durability will vary by product
or product group.
Note 2 to entry: The end state can be based on technological, social or economic aspects.
Note 3 to entry: Durability can be expressed in units appropriate to the part or product concerned, e.g. calendar
time, operating cycles, distance run, etc. or the probability of being able to achieve a given period of usage. The
units should always be clearly stated.
Note 4 to entry: Durability as a measure relates to the longevity of the interval.
[SOURCE: IEC 60050-192:2015, 192-01-21, modified – "end of useful life" has been replaced
with "defined end state", and notes to entry have been added.]

3.1.11
integrity
ability to prevent or withstand unauthorised modification
Note 1 to entry: Modification can involve hardware, software or data.
3.1.12
life profile
stresses and their levels, content, duration and sequence encountered during the life of an item
Note 1 to entry: Stresses can be internal (such as operating cycles) or external (such as environmental stress, input
power level, or rate of service requests over a network).
Note 2 to entry: Life profile can be actual, expected or predicted.
3.1.13
maintainability
ability to be retained in, or restored to a state to perform as required, under given conditions
Note 1 to entry: Given conditions include location for maintenance, accessibility, maintenance procedures and
maintenance resources as well as conditions defined in the life profile.
Note 2 to entry: Maintainability can be quantified using appropriate measures. See IEC 60050-192:2015, 192-07,
Maintainability and maintenance support measures.
3.1.14
measurement
process of experimentally obtaining one or more values that can reasonably be attributed to a
quantity
Note 1 to entry: Measurement does not apply to nominal properties.
Note 2 to entry: Measurement implies comparison of quantities, including counting of entities.
Note 3 to entry: Measurement presupposes a description of the quantity commensurate with the intended use of a
measurement result, a measurement procedure, and a calibrated measuring system operating according to the
specified measurement procedure, including the measurement conditions.
Note 4 to entry: The French word "mesure" has several meanings in everyday French language. It is for this reason
that the French word "mesurage" has been introduced to describe the act of measurement. Nevertheless, the French
word "mesure" occurs many times in forming terms, following current usage, and without ambiguity. Examples are:
unité de mesure (unit of measurement), méthode de mesure (measurement method), instrument de mesure
(measurement instrument). This does not mean that the use of the French word "mesurage" in place of "mesure" in
such terms is not permissible when advantageous.
[SOURCE: ISO/IEC GUIDE 99:2007, 2.1, modified – Note 4 to entry has been added.]
3.1.15
need
prerequisite identified as necessary, to achieve an intended outcome, implied or stated, within
a specific context of use
– 12 – IEC 60300-1:2024 © IEC 2024
3.1.16
reliability
ability to perform as required, without failure, for a given interval under given conditions
Note 1 to entry: The interval can be expressed in units appropriate to the item concerned, for example calendar
time, operating cycles, distance run, etc., and the units should always be clearly stated.
Note 2 to entry: Given conditions include aspects that affect reliability such as: mode of operation, stress levels,
environmental conditions and maintenance.
Note 3 to entry: Reliability can be quantified using measures defined in IEC 60050-192:2015, 192-05, Reliability
related concepts: measures.
[SOURCE: IEC 60050-192:2015, 192-01-24, modified – in the definition "of an item" and "time"
have been deleted.]
3.1.17
requirement
statement which translates or expresses a need and its associated
constraints and conditions
Note 1 to entry: Requirements exist at different levels in the system structure.
Note 2 to entry: A requirement is an expression of one or more particular needs in a very specific, precise and
unambiguous manner.
Note 3 to entry: A requirement always relates to a system, software or service, or other item of interest.
Note 4 to entry: A requirement is a statement where evidence or assurance of compliance can be provided.
[SOURCE: ISO/IEC/IEEE 29148:2018, 3.1.19, modified – Note 4 to entry has been added.]
3.1.18
risk
effect of uncertainty on objectives
Note 1 to entry: An effect is a deviation from the expected. It can be positive or negative or both and can address,
create or result in opportunities and threats.
Note 2 to entry: Objectives can have different aspects and categories and can be applied at different levels.
Note 3 to entry: Risk is usually expressed in terms of risk sources, potential events, their consequences and their
likelihood.
[SOURCE: ISO 31000:2018, 3.1]
3.1.19
safety
freedom from unacceptable risk of physical injury or damage to the health of people or damage
to property or the environment
3.1.20
security
protection against intentional subversion or forced failure

3.1.21
specification
information item that identifies the dependability requirements and goals of
a system, product or service together with any supporting information
Note 1 to entry: Supporting information can include details of use, operating and environmental conditions, failure
criteria and methods intended to be applied for assurance of compliance with requirements, including accept or reject
criteria.
Note 2 to entry: ISO/IEC/IEEE 15289 defines a specification as an information item that identifies in a complete,
precise and verifiable manner the requirements, design, behaviour or other expected characteristics of the system,
service or process. The specification of dependability has a greater scope than that used in ISO/IEC/IEEE 15289.
3.1.22
stakeholder
person or organization that can affect, be affected by, or perceive themselves to be affected by
a decision or activity
EXAMPLE: End users, end user organizations, suppo
...