ISO 13381-1:2025

FINAL DRAFT
International
Standard
ISO/FDIS 13381-1
ISO/TC 108/SC 5
Condition monitoring and
Secretariat: SA
diagnostics of machine systems —
Voting begins on:
Prognostics —
2025-06-12
Part 1:
Voting terminates on:
2025-08-07
General guidelines and
requirements
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 SUPPOR TING DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
ISO/FDIS 13381-1:2025(en) © ISO 2025

FINAL DRAFT
ISO/FDIS 13381-1:2025(en)
International
Standard
ISO/FDIS 13381-1
ISO/TC 108/SC 5
Condition monitoring and
Secretariat: SA
diagnostics of machine systems —
Voting begins on:
Prognostics —
Part 1:
Voting terminates on:
General guidelines and
requirements
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 SUPPOR TING DOCUMENTATION.
© ISO 2025
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
or ISO’s member body in the country of the requester.
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland Reference number
ISO/FDIS 13381-1:2025(en) © ISO 2025

ii
ISO/FDIS 13381-1:2025(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Data requirements . 2
5 Prognosis concepts . 4
5.1 Basic concepts .4
5.2 Influence factors .5
5.3 Trending, setting alert, alarm, and trip (shutdown) limits .7
5.4 Multiple parameter analysis .9
5.5 Initiation criteria .11
5.6 Prognosis of failure mode initiation . . 12
6 Failure and deterioration models used for prognostics . 14
6.1 Failure mode behaviour modelling concepts .14
6.2 Modelling types .14
6.3 Artifical intelligence (AI) and machine learning (ML) . 15
7 Generic prognosis process .15
7.1 Prognosis confidence levels . 15
7.2 Prognosis process .16
7.2.1 General .16
7.2.2 Pre-processing .16
7.2.3 Existing failure mode prognosis process .16
7.2.4 Future failure mode prognosis process .16
7.2.5 Post-action prognosis .17
7.3 Prognosis report .17
Annex A (informative) Condition monitoring flow chart . 19
Annex B (informative) Example prognosis confidence level determination .20
Annex C (informative) Failure modelling techniques .21
Bibliography .23

iii
ISO/FDIS 13381-1:2025(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO 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, ISO 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
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 108, Mechanical vibration, shock and condition
monitoring, Subcommittee SC 5, Condition monitoring and diagnostics of machine systems.
This third edition cancels and replaces the second edition (ISO 13381-1:2015), which has been technically
revised.
The main changes are as follows:
— update of definitions (for clarification purposes);
— revised data requirements;
— revised modelling types;
— revised failure modelling techniques (see Annex C);
— update of Bibliography.
A list of all parts in the ISO 13381 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
ISO/FDIS 13381-1:2025(en)
Introduction
The complete process of machine condition monitoring consists of five distinct phases:
a) detection of problems (deviations from normal conditions);
b) diagnosis of the faults and their causes;
c) prognosis of future fault progression;
d) recommendation of actions;
e) post-mortems.
Machine health prognosis demands prediction of future machine integrity and deterioration so there can be
no exactitude in the process. Instead, prognosis requires statistical or testimonial approaches to be adopted.
Standardization in machine health prognosis therefore embodies guidelines, approaches, and concepts
rather than strict procedures or standard methodologies.
Prognosis of future fault progressions requires foreknowledge of the probable failure modes, future duties
to which the machine will or might be subjected, and a thorough understanding of the relationships between
failure modes and operating conditions. This may require an understanding of the physics underlying
the fault modes and demand the collection of previous duty and cumulative duty parameters, previous
maintenance history, inspection results, run-to-failure data, trajectories and associated operational data,
along with condition and performance parameters prior to extrapolations, projections and forecasts.
Prognosis processes need to be able to accommodate analytical damage models.
As computing power increases, and data storage decreases in cost, multiple-parameter analysis becomes
more complex and modelling becomes more sophisticated. Thus, the ability to predict the progression of
damage accumulation is achievable if the initiation criterion is known (expressed as a set of parameter
values for a given mode) in addition to future behaviour for a given set of conditions.

v
FINAL DRAFT International Standard ISO/FDIS 13381-1:2025(en)
Condition monitoring and diagnostics of machine systems —
Prognostics —
Part 1:
General guidelines and requirements
1 Scope
This document provides guidance and requirements for the development and application of prognosis
processes. It is intended to
a) allow developers, providers, users and manufacturers to share common concepts of prognostics,
b) enable users to determine the data, characteristics, processes and behaviours necessary for accurate
prognosis,
c) outline appropriate approaches and processes to prognostics development, and
d) introduce prognostics concepts in order to facilitate future systems and training.
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.
ISO 2041, Mechanical vibration, shock and condition monitoring — Vocabulary
ISO 13372, Condition monitoring and diagnostics of machines — Vocabulary
ISO 13379-1, Condition monitoring and diagnostics of machines — Data interpretation and diagnostics
techniques — Part 1: General guidelines
ISO 17359, Condition monitoring and diagnostics of machines — General guidelines
3 Terms and definitions
For the purposes of this document, the terms and definitions given in
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ISO/FDIS 13381-1:2025(en)
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ISO/TC 108/SC 5
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Secretariat: SA
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Date: 2025-05-24xx .
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Condition monitoring and diagnostics of machine systems —
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Prognostics —
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Part 1:
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General guidelines and requirements
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ISO/FDIS 13381-1:2025(en) Formatted: Font: Bold
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Commented [eXtyles1]: The reference "ISO 2025" is to a
withdrawn standard
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
Formatted: Default Paragraph Font
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,
Formatted: Default Paragraph Font
or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO
at the address below or ISO'sISO’s member body in the country of the requester.
ISO Copyright Officecopyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva Formatted: zzCopyright address, Adjust space between Latin
and Asian text, Adjust space between Asian text and numbers
Phone: + 41 22 749 01 11
Formatted: French (France)
Email: copyright@iso.org
E-mail: copyright@iso.org
Website: www.iso.orgwww.iso.org
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been redirected to https://www.iso.org/home.html. Please verify the
URL.
Published in Switzerland.
Formatted: zzCopyright address, Adjust space between Latin
and Asian text, Adjust space between Asian text and numbers

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ii
ISO/FDIS 13381-1:2025(en) Formatted: Font: Bold
Formatted: HeaderCentered, Left
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Contents Page
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at 0.71 cm
Foreword . v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Data requirements . 3
5 Prognosis concepts . 4
5.1 Basic concepts . 4
5.2 Influence factors . 5
5.3 Trending, setting alert, alarm, and trip (shutdown) limits . 7
5.4 Multiple parameter analysis . 9
5.5 Initiation criteria . 10
5.6 Prognosis of failure mode initiation . 11
6 Failure and deterioration models used for prognostics . 13
6.1 Failure mode behaviour modelling concepts . 13
6.2 Modelling types . 13
6.3 Artifical intelligence (AI) and machine learning (ML) . 14
7 Generic prognosis process. 14
7.1 Prognosis confidence levels . 14
7.2 Prognosis process . 15
7.3 Prognosis report . 16
Annex A (informative) Condition monitoring flow chart . 18
Annex B (informative) Example prognosis confidence level determination . 19
Annex C (informative) Failure modelling techniques . 20
Bibliography . 22

Foreword . 4
Introduction . 5
1 Scope . 5
2 Normative references . 6
3 Terms and definitions . 6
4 Data requirements . 7
5 Prognosis concepts . 9
5.1 Basic concepts . 9
5.2 Influence factors . 10
5.3 Trending, setting alert, alarm, and trip (shutdown) limits . 11
5.4 Multiple parameter analysis . 12
5.5 Initiation criteria . 13
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5.6 Prognosis of failure mode initiation . 13
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stops: Not at 17.2 cm
6 Failure and deterioration models used for prognostics . 14
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6.1 Failure mode behaviour modelling concepts . 14
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6.2 Modelling types . 15
pt, Tab stops: Not at 17.2 cm
iii
ISO/FDIS 13381-1:2025(en) Formatted: Font: Bold
Formatted: HeaderCentered
6.3 Artifical Intelligence (AI) and Machine Learning (ML) . 15
7 Generic prognosis process. 16
7.1 Prognosis confidence levels . 16
7.2 Prognosis process . 17
7.2.1 General. 17
7.2.2 Pre-processing . 17
7.2.3 Existing failure mode prognosis process . 17
7.2.4 Future failure mode prognosis process . 17
7.2.5 Post-action prognosis . 18
7.3 Prognosis report . 18
Annex A (informative) Condition monitoring flow chart . 20
Annex B (informative) Example prognosis confidence level determination . 21
Annex C (informative) Failure modelling techniques . 22
C.1 Five general modelling approaches . 22
C.1.1 Physics-based models . 22
C.1.2 Statistical models . 22
C.1.3 Heuristic models . 22
C.1.4 Data-driven models . 22
C.1.5 Hybrid models . 22
C.2 Three modelling applications . 22
C.2.1 Life expectancy . 22
C.2.2 Reliability models . 23
C.2.3 Deterioration models . 23
C.3 Model validation. 23
Bibliography . 24

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iv
ISO/FDIS 13381-1:2025(en) Formatted: Font: Bold
Formatted: HeaderCentered, Left
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Foreword
Adjust space between Asian text and numbers
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates clos
...