oSIST prEN 17666:2021

Maintenance - Maintenance engineering - Requirements

This document describes the generic principles, criteria and contents of maintenance engineering. This includes guidance on methods and techniques which are used to sustain the required functions of items at any stage of their life cycle.
This document gives guidance on how maintenance engineering can contribute to assure the required integrity, safety, reliability and maintainability to achieve a sustainable balance between performance, risk and costs.
This document refers to standards that further describe detailed methods and techniques.

Instandhaltung - Instandhaltungsengineering - Anforderungen

Dieses Dokument legt die Disziplin des Instandhaltungsengineerings über den gesamten Lebenszyklus fest.
Dieses Dokument enthält Anleitungen dazu, wie das Instandhaltungsengineering zur Sicherstellung der geforderten Funktionssicherheit beitragen kann, um einen nachhaltigen Ausgleich zwischen Leistung, Risiko und Kosten zu erreichen.
Dieses Dokument verweist auf Normen, in denen detaillierte Methoden und Techniken ausführlicher beschrieben werden.
Dieses Dokument enthält keine Anleitungen dazu, wie Instandhaltungsengineering-Systeme und  Infrastruktur zu erstellen sind, noch enthält es Anleitungen für die Instandhaltung von Software.
ANMERKUNG 1   Die Instandhaltungstätigkeiten für die Softwarekomponenten eines Objekts werden in ISO/IEC/IEEE 14764 [54] behandelt.
ANMERKUNG 2   Der allgemeine Instandhaltungsprozess wird in EN 17007 [10] behandelt.

Maintenance - Ingénierie de maintenance - Exigences

Le présent document spécifie la discipline d’ingénierie de maintenance tout au long du cycle de vie.
Il fournit également des recommandations sur la façon dont l’ingénierie de maintenance peut contribuer à assurer la sûreté de fonctionnement requise afin d’établir un équilibre durable entre performances, risques et coûts.
Le présent document se réfère à des normes qui décrivent plus en détail les méthodes et techniques concernées.
Il ne fournit aucune recommandation pour la mise en place de systèmes et d’infrastructure pour l’ingénierie de maintenance, ni aucune recommandation sur la maintenance des logiciels.
NOTE 1   Pour les composants logiciels d’un bien, les activités de maintenance sont traitées dans l’ISO/IEC/IEEE 14764 [54].
NOTE 2   Le processus global de maintenance est couvert par l’EN 17007 [10].

Vzdrževanje - Vzdrževalni inženiring - Zahteve

General Information

• Status: Not Published
• Public Enquiry End Date: 30-Jun-2021
• ICS: 03.080.10 - Maintenance services. Facilities management
• Technical Committee: VZD - Maintenance
• Current Stage: 5020 - Formal vote (FV) (Adopted Project)
• Start Date: 08-Aug-2022
• Due Date: 26-Sep-2022
• Ref Project: FprEN 17666 - Maintenance - Maintenance engineering - Requirements

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN 17666:2021
01-junij-2021
Vzdrževanje - Vzdrževalni inženiring - Zahteve
Maintenance - Maintenance engineering - Requirements
Instandhaltung - Instandhaltungsengineering - Anforderungen
Ta slovenski standard je istoveten z: prEN 17666
ICS:
03.080.10 Vzdrževalne storitve. Maintenance services.
Upravljanje objektov Facilities management
oSIST prEN 17666:2021 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 17666:2021
DRAFT
EUROPEAN STANDARD
prEN 17666
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2021
ICS 03.080.10
English Version
Maintenance - Maintenance engineering - Requirements
Instandhaltung - Instandhaltungsengineering -
Anforderungen

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 319.

If this draft becomes a European Standard, CEN 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.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other

language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC

Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 17666:2021 E

worldwide for CEN national Members.
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Contents Page

European foreword ....................................................................................................................................................... 4

Introduction .................................................................................................................................................................... 5

1 Scope .................................................................................................................................................................... 6

2 Normative references .................................................................................................................................... 6

3 Terms and definitions ................................................................................................................................... 6

4 Symbols and abbreviations ...................................................................................................................... 12

5 Maintenance engineering elements ...................................................................................................... 13

5.1 Principles and objectives .......................................................................................................................... 13

5.1.1 General ............................................................................................................................................................. 13

5.1.2 Maintenance engineering goals and objectives ................................................................................ 15

5.2 Information for maintenance engineering ......................................................................................... 16

5.2.1 Asset taxonomy ............................................................................................................................................. 16

5.2.2 Data requirements ....................................................................................................................................... 18

5.2.3 Maintenance documentation ................................................................................................................... 19

5.3 Determination of failure management policies ................................................................................ 19

5.3.1 General ............................................................................................................................................................. 19

5.3.2 Operational and maintenance functional requirements ............................................................... 21

5.3.3 Identify the functional requirements and failure modes .............................................................. 21

5.3.4 Develop the maintenance tasks .............................................................................................................. 22

5.3.5 Determine the task frequencies .............................................................................................................. 23

5.3.6 Corrective maintenance ............................................................................................................................. 23

5.3.7 Define the spare parts requirements .................................................................................................... 24

5.3.8 Development of preventive maintenance (PM) program .............................................................. 25

5.4 Cost estimates ................................................................................................................................................ 25

5.4.1 Costs related to organization, manning and support ...................................................................... 25

5.4.2 Justify failure management policy ......................................................................................................... 26

5.5 Asset performance and continuously improvement ....................................................................... 26

5.5.1 Report the review results .......................................................................................................................... 26

5.5.2 Analyse the need for improvements ..................................................................................................... 26

5.5.3 Report technical data and assess technical condition .................................................................... 26

6 Maintenance engineering in the life cycle ........................................................................................... 27

6.1 Life cycle stages ............................................................................................................................................. 27

6.2 Objectives and roles of maintenance engineering for each life cycle stage ............................ 28

6.3 Maintenance engineering activities during the life cycle stages ................................................ 31

6.4 Concept stage ................................................................................................................................................. 33

6.4.1 Objectives for concept stage ..................................................................................................................... 33

6.4.2 Feasibility substage ..................................................................................................................................... 34

6.4.3 Concept baseline substage ........................................................................................................................ 34

6.4.4 Maintenance engineering in the concept stage ................................................................................. 34

6.5 Development stage ...................................................................................................................................... 35

6.5.1 Objectives for the development stage .................................................................................................. 35

6.5.2 Preliminary design ...................................................................................................................................... 35

6.5.3 Detailed design ............................................................................................................................................. 38

6.6 Realization stage .......................................................................................................................................... 40

6.6.1 General ............................................................................................................................................................. 40

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6.6.2 Maintenance engineering in the realization stage ........................................................................... 40

6.7 Utilization stage............................................................................................................................................. 41

6.8 Disposal/transition stage .......................................................................................................................... 43

7 Performance assessment through indicators .................................................................................... 44

8 The Digitalization of maintenance engineering ................................................................................ 44

8.1 General ............................................................................................................................................................. 44

8.2 Implementation steps ................................................................................................................................. 45

8.3 Risks associated with digitalization ...................................................................................................... 45

8.4 Recommendations ........................................................................................................................................ 46

Annex A (informative) Relationship between maintenance engineering and integrated

logistics support (ILS) ................................................................................................................................. 47

A.1 ILS goals ............................................................................................................................................................ 47

A.2 ILS areas ........................................................................................................................................................... 47

A.3 ILS elements .................................................................................................................................................... 47

A.4 LSA Methodology .......................................................................................................................................... 48

A.5 ILS methodology per life cycle stages .................................................................................................... 49

Annex B (informative) Map of CEN/TC 319 Maintenance standards ...................................................... 51

B.1 The map of CEN/TC 319 standards ........................................................................................................ 51

B.2 Description of the groups of standards ................................................................................................ 53

B.2.1 Common basis ................................................................................................................................................ 53

B.2.2 Management ................................................................................................................................................... 53

B.2.3 Methodologies ................................................................................................................................................ 53

B.2.4 Resources ........................................................................................................................................................ 53

Annex C (informative) Maintenance activities and shutdown requirements ...................................... 54

Annex D (informative) Maintenance engineering techniques and analysis......................................... 58

Annex E (informative) Examples of performance indicators for maintenance engineering ......... 74

E.1 Introduction to indicators ......................................................................................................................... 74

E.2 Performance indicators for maintenance engineering .................................................................. 74

E.3 Use of indicators in the different maintenance engineering steps ............................................. 75

E.4 Examples of performance indicators for maintenance engineering ......................................... 76

Annex F (informative) The digitalization of maintenance engineering ................................................. 80

F.1 Introduction.................................................................................................................................................... 80

F.2 Maintenance using digitalized data ....................................................................................................... 80

F.3 Artificial Intelligence Analytics applied to Maintenance Engineering ...................................... 80

F.4 Ethics of Artificial intelligence (AI) ........................................................................................................ 81

Annex G (informative) Establishing a technical hierarchy ......................................................................... 82

Annex H (informative) Checklist for maintainability design within maintenance

engineering ..................................................................................................................................................... 84

Bibliography ................................................................................................................................................................. 87

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European foreword

This document (prEN 17666:2021) has been prepared by Technical Committee CEN/TC 319

“Maintenance”, the secretariat of which is held by UNI.
This document is currently submitted to the CEN Enquiry.
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Introduction

Maintenance engineering is a discipline applying competencies, methods, techniques and tools to develop

and support maintenance in order to ensure that an item is able to perform its required functions in a

safe, sustainable and cost-effective manner throughout the life cycle.

The prime objective of maintenance engineering is to contribute to the achievement of overall

stakeholder requirements through optimized and cost-effective maintenance as part of physical asset

management. The scale or scope of maintenance engineering varies depending on the complexity of the

physical asset, its technical condition, the organization, and its degree of authority to influence design

and maintenance.

The benefits of the contributions from maintenance engineering include, but are not limited to:

— achievement of maintainability and availability goals by influencing design;
— risk analysis related to maintenance;
— application of sustainability principles;
— achieved required integrity and safety level;
— achieved required performance and technical condition;
— improved life extension decisions;
— improved maintenance support performance;

— reduced environmental footprint by saving energy and raw materials consumption;

— improved competitiveness and output value.

This standard is generic and provides guidance on the methodology to achieve maintenance engineering

objectives. The intended users of this standard are personnel involved in design, procurement,

construction, commissioning, operation, improvement, maintenance and disposal/transition or

decommissioning of physical assets. No specific structure or size of organization is assumed so that

maintenance engineering effort should be tailored to suit specific applications and organisational

requirements.

While maintenance engineering has the most impact when applied during the concept stage and design

of a physical item, this standard is applicable to maintenance engineering in all life cycle stages, and for

different scenarios, for example
— manufacturer producing one equipment and then maintaining it.

— transfer of property at commissioning to a buyer who will be in charge of maintenance.

— transfer of property at commissioning followed by a warranty period. The seller is responsible during

the warranty and the buyer thereafter.

— maintenance service (sub) contract by the seller to the buyer or to a third party.

This standard is part of a group of standards published by CEN/TC 319 giving guidance on maintenance,

see Annex B and the committee site on www.cen.eu:

https://standards.cen.eu/dyn/www/f?p=204:7:0::::FSP_ORG_ID:6300&cs=1A64AA79FCFDE906561AF

DA09269B3123
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1 Scope

This document describes the generic requirements, criteria and contents of maintenance engineering.

This includes guidance on methods and techniques which are used to sustain the required functions of

items at any stage of their life cycle.

This document gives guidance on how maintenance engineering can contribute to the assurance of

required integrity, safety, reliability, maintainability and availability to achieve a sustainable balance

between performance, risk and costs.

This document does not give guidance on how to set up systems and infrastructure to support the

maintenance engineering function.

This document refers to standards that further describe detailed methods and techniques.

NOTE The overall maintenance process and management is covered by other CEN/TC 319 standards EN 17007

[10] and prEN (WG 8).
2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

EN 13306:2017, Maintenance - Maintenance terminology
EN 15628, Maintenance - Qualification of maintenance personnel
3 Terms and definitions

For the purposes of this document the terms and definitions given in EN 13306:2017, EN 15628 and the

following apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— IEC Electropedia: available at https://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
maintenance

combination of all technical, administrative and managerial actions during the life cycle (3.13) of an item

(3.7) intended to retain it in, or restore it to, a state in which it can perform the required function (3.8)

Note 1 to entry: Technical maintenance actions include observation and analyses of the item state (e.g.

inspection, monitoring, testing, diagnosis, prognosis, etc.) and active maintenance actions (e.g. repair,

refurbishment).

Note 2 to entry: See also the definitions of improvement and modification in EN 13306 [2].

[SOURCE: EN 13306:2017, 2.1]
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3.2
operation

combination of all technical, administrative and managerial actions, other than maintenance actions, that

results in the item being in use

Note 1 to entry: Maintenance actions carried out by operators are not included in operation.

Note 2 to entry: In this document, operational and operations are used as synonyms.

[SOURCE: EN 13306:2017, 2.9]
3.3
engineering

branch of science and technology concerned with the design, building, use and disposal of engines,

machines and structures
3.4
maintenance engineering

engineering (3.3) discipline applying competencies (3.10), methods, techniques and tools to develop and

support maintenance (3.1) in order to assure that an item (3.7) is able to perform its required functions

(3.8) in a safe, sustainable and cost-effective (3.6) manner throughout the life cycle (3.13)

3.5
maintenance management

all activities of the management that determine the maintenance (3.1) requirements, objectives,

strategies and responsibilities, and implementation of them by such means as maintenance planning,

maintenance control, and the improvement of maintenance activities and economics
[SOURCE: EN 13306:2017, 2.2]
3.6
cost-effective

balance of cost, risk, opportunity and performance taking into account stakeholder objectives

Note 1 to entry: Performance covers quality, short and long term.
3.7
item

part, component, device, subsystem, functional unit, equipment or system that can be individually

described and considered

Note 1 to entry: A number of items e.g. a population of items, or a sample, may itself be considered as an item.

Note 2 to entry: An item may consist of hardware, software or both.

Note 3 to entry: Software consists of programs, procedures, rules, documentation and data of an information

processing system.
Note 4 to entry: Services is included.
Note 5 to entry: Systems may include people.
[SOURCE: EN 13306:2017, modified — Note 4 and 5 to entry are added]
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3.8
required function

function, combination of functions, or a total combination of functions of an item which are considered

necessary to fulfil a given requirement

Note 1 to entry: “Necessary to fulfil a given requirement” may also include asset value preservation.

Note 2 to entry: The given requirement may be expressed or implied and may in some cases be below the original

design specifications.

Note 3 to entry: The required function, by implication, also covers what the item shall not do.

[SOURCE: EN 13306:2017, 2.6]
3.9
physical asset
item (3.7) that has potential or actual value to an organization

Note 1 to entry: Examples of physical assets are components, machines, plants, buildings, infrastructures, etc.

Physical asset and technical system are often used as synonyms.
[SOURCE: EN 13306:2017, 3.2, modified — Added the last sentence in the note.]
3.10
competence

proven ability to use knowledge, skills (3.11), and personal, social and/or methodological abilities, in

work or study situations and in professional and personal development

Note 1 to entry: Competence is described in the terms of responsibility and autonomy.

[SOURCE: EN 15628:2014, 3.1]
3.11
skills

ability to apply knowledge and use know-how to complete tasks and resolve problems

Note 1 to entry: Skills are described as cognitive (involving the use of logical, intuitive and creative thinking) or

practical (involving manual dexterity and the use of methods, tools and instruments).

3.12
criticality

numerical index of the severity of a failure or a fault combined with the probability

or frequency of its occurrence

Note 1 to entry: The numerical index in this context may be defined, for example, as an area in the frequency of

failure occurrence - severity matrix diagram (see Annex E in EN 13306:2017).
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3.13
life cycle
series of stages through which an item goes, from its conception to disposal

EXAMPLE: A typical system lifecycle consists of acquisition, operation, maintenance, modernisation,

decommissioning and/or disposal

Note 1 to entry: The stages identified will vary with the application. Reuse and recycle follows disposal.

[SOURCE: EN 13306:2017, 4.18]
3.14
life cycle cost
sum of the costs generated during the life cycle (3.13) of the item (3.7)

Note 1 to entry: For a user or an owner of an item, the total life cycle cost may include only those costs pertaining

to acquisition, operation, maintenance and disposal.
[SOURCE: EN 13306:2017, 11.1]
3.15
indicator

quantitative or qualitative measure of a characteristic or a set of characteristics of a phenomenon or

performance of activities, according to defined criteria or a given formula or questionnaire

Note 1 to entry: The indicators are a tool for development and implementation of a strategy for monitoring

progress towards the goals outlined in the strategy.
[SOURCE: EN 15341:2019, 3.3]
3.16
key performance indicator
KPI
indicator (3.15) considered significant
[SOURCE: EN 15341:2019, 34]
3.17
maintenance plan

structured and documented set of tasks that include the activities, procedures, resources and the time

scale required to carry out maintenance (3.1)
[SOURCE: EN-ISO 41011:2018, 2.5]
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3.18
dependability
ability to perform as and when required

Note 1 to entry: Dependability includes availability (3.22), safety, security, durability, economics and their

influencing factors (reliability, maintainability (3.21), supportability (3.19), conditions of use and operators

influence).

Note 2 to entry: Dependability is used as a collective term for the time-related quality characteristics of an item.

[SOURCE: EN 13306:2017, 2.7, modified — In Note 1 to entry “maintenance support performance” is

replaced by “supportability”]
3.19
supportability

ability to be supported to sustain the required availability with a defined operational profile and given

logistic and maintenance resources

Note 1 to entry: Supportability of an item results from the inherent maintainability, combined with factors

external to the item that affect the relative ease of providing the required maintenance and logistic support.

[SOURCE: IEC 60050-192:2015, 192-01-31]
3.20
integrated logistics support
ILS

management process to determine and coordinate the provision of all materials and resources required

to meet the needs for operation and maintenance

Note 1 to entry: ILS is a process to determine the optimal maintenance support. ILS integrates logistics support

analysis and the development of resources, see Annex A.
[SOURCE: IEC 60050-192: 2015, 192-01-30, modified — Note 1 to entry added]
3.21
maintainability

ability of an item under given conditions of use, to be retained in, or restored to, a state in which it can

perform a required function (3.8), when maintenance (3.1) is performed under given conditions and using

stated procedures and resources

Note 1 to entry: Maintainability may be quantified using appropriate measures or indicators and is then referred

to as maintainability performance.
[SOURCE: EN 13306:2017, 4.5]
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3.22
availability

ability of an item to be in a state to perform as and when required, under given conditions, assuming that

the necessary external resources are provided

Note 1 to entry: Required external resources, other than maintenance resources, do not affect the availability of

the item although the item may not be available from the user’s viewpoint.

Note 2 to entry: This ability depends on the combined aspects of the reliability, maintainability of the item, the

maintenance supportability and the maintenance actions carried out on the item.

Note 3 to entry: Availability may be quantified using appropriate measures or indicators and is then referred to

as availability performance (see EN 13306:2017, 4.9).

Note 4 to entry: There are several types of availability, for example: achieved availability (3.23), operational

availability (3.24) and inherent availability (3.25).
[SOURCE: EN 13306:2017, 4.7, modified — Note 4 to entry added]
3.23
achieved availability

probability than an item when used under stated conditions in an ideal support environment will operate

in a satisfactorily at any point in time
3.24
operational availability

availability (3.22) experienced under actual conditions of operation and maintenance

Note 1 to entry: Operational availability is determined considering down time due to failures and associated

delays, but excluding external causes.
[SOURCE: IEC 60050-192: 2015, 192-08-03]
3.25
inherent availability
availability (3.22) provided by t
...