ISO/FDIS 17507-1

Natural gas — Calculation of methane number of gaseous fuels for reciprocating internal combustion engines — Part 1: MNc method

Part 1 of ISO 17507 describes the calculation method for the methane number of a gaseous fuel according to the methodology first proposed Deutz (“Klöckner-Humboldt-Deutz AG”) and later amended by MWM (“Motoren-Werke Mannheim AG”).

Gaz naturel — Calcul de l'indice de méthane des combustibles gazeux pour les moteurs alternatifs à combustion interne — Partie 1: Méthode IMc

General Information

• Status: Not Published
• ICS: 75.060 - Natural gas
• Technical Committee: ISO/TC 193 - Natural gas
• Drafting Committee: ISO/TC 193 - Natural gas
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 01-Aug-2025
• Completion Date: 01-Aug-2025

Standards Content (Sample)

FINAL DRAFT
International
Standard
ISO/TC 193
Natural gas — Calculation of
Secretariat: NEN
methane number of gaseous
Voting begins on:
fuels for reciprocating internal
2025-08-01
combustion engines —
Voting terminates on:
2025-09-26
Part 1:
MNc method
Gaz naturel — Calcul de l'indice de méthane des combustibles
gazeux pour les moteurs alternatifs à combustion interne —
Partie 1: Méthode IMc
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-
ISO/CEN PARALLEL PROCESSING 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
FINAL DRAFT
International
Standard
ISO/TC 193
Natural gas — Calculation of
Secretariat: NEN
methane number of gaseous
Voting begins on:
fuels for reciprocating internal
combustion engines —
Voting terminates on:
Part 1:
MNc method
Gaz naturel — Calcul de l'indice de méthane des combustibles
gazeux pour les moteurs alternatifs à combustion interne —
Partie 1: Méthode IMc
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-
ISO/CEN PARALLEL PROCESSING
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: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 MN method . 2
C
5.1 Introduction .2
5.2 Applicability .2
5.2.1 Standard gaseous fuel composition range .2
5.2.2 Handling of other gaseous fuel components .3
5.3 Methodology to calculate the MN .4
C
5.4 Expression of results . .4
5.5 Uncertainty error and bias .4
6 Example calculations . 5
6.1 Example 1 .5
6.1.1 Simplification of the composition of the gaseous fuel . .5
6.1.2 Selection of the ternary systems .5
6.1.3 Sub-division of the inert-free mixture into the selected partial mixtures .8
6.1.4 Calculation of the methane number of the partial mixtures .8
6.1.5 Criteria for not using ternary systems for final calculation of the MN .9
C
6.1.6 Adjustment of the composition and fraction of the partial mixtures .9
6.1.7 Calculation of the methane number of the simplified mixture.10
6.1.8 Calculation of the methane number of the gaseous fuel .10
6.2 Example 2 .10
6.2.1 Simplification of the composition of the gaseous fuel . .10
6.2.2 Calculation of fitness of the ternary systems .11
6.2.3 Selection of ternary mixtures.11
6.2.4 Calculation of the methane number .11
6.3 Example 3 .11
6.3.1 Simplification of the composition of the gaseous fuel . .11
6.3.2 Calculation of fitness of the ternary systems .11
6.3.3 Selection of ternary mixtures. 12
6.3.4 Calculation of the methane number . 12
6.3.5 Additional numerical examples . 13
Annex A (normative) Numerical results of calculations for a variety of compositions for
software validation purposes . 14
Annex B (informative) Tools for users of the MN Method .28
C
Annex C (normative) Uncertainty error and bias .29
Annex D (informative) Natural gas-based fuels for reciprocating internal combustion engines .31
Annex E (informative) Basis of the MN method .32
C
Bibliography .37

iii
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 193, Natural gas.
A list of all parts in the ISO 17507 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
Introduction
The globalization of the natural gas market and the drive towards sustainability are increasing the diversity
of the supply of gases to the natural gas infrastructure. For example, the introduction of regasified liquefied
natural gas (LNG) can result in higher fractions of non-methane hydrocarbons in the natural gas grid
than the traditionally distributed pipeline gases for which these hydrocarbons have been removed during
processing. Also, the drive towards sustainable gaseous fuels, such as hydrogen and gases derived from
biomass, results in the introduction of “new” gas compositions that contain components that do not occur
in the traditional natural gas supply. Consequently, the increasing variations in gas composition affect the
knock resistance of the gas when used as a fuel. This can affect the operational integrity of reciprocating
internal combustion engines.
For the efficient and safe operation of gas engines, it is of great importance to characterize the knock
resistance of gaseous fuels accurately. Engine knock is caused by the autoignition of unburned fuel
mixture ahead of this mixture being consumed by the propagating flame. Mild engine knock increases
pollutant emissions accompanied by gradual build-up of component damage and complete engine failure
if not counteracted. Severe knock causes structural damage to critical engine parts, which can quickly
lead to catastrophic engine failure. To ensure that gas engines are matched with the expected variations
in fuel composition, the knock resistance of the fuel is to be characterized, and subsequently specified,
unambiguously.
Traditional methods for characterizing the knock resistance of gaseous fuels, such as the methane number
method developed by Anstalt für Verbrennungskraftmaschinen List (AVL) in the 1960s, relate the k
...

ISO/TC 193
Secretariat: NEN
Date: 2025-07-17
Natural gas — Calculation of methane number of gaseous fuels for
reciprocating internal combustion engines —
Part 1:
MNc method
Gaz naturel — Calcul de l'indice de méthane des combustibles gazeux pour les moteurs alternatifs à combustion
interne —
Partie 1: Méthode IMc
FDIS stage
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spacing: single
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All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,
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’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
E-mail: [e-mail]
Website: www.iso.org
Published in Switzerland
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ii © ISO 2024 2025 – All rights reserved
ii
ISO/FDIS 17507-1:2025(en)
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Line spacing: single
Contents
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Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 MN method . 2
C
5.1 Introduction . 2
5.2 Applicability . 2
5.3 Methodology to calculate the MNC . 4
5.4 Expression of results . 5
5.5 Uncertainty error and bias . 5
6 Example calculations . 5
6.1 Example 1 . 5
6.2 Example 2 . 12
6.3 Example 3 . 13
Annex A (normative) Numerical results of calculations for a variety of compositions for
software validation purposes . 16
Annex B (informative) Tools for users of the MN Method . 40
C
Annex C (normative) Uncertainty error and bias . 41
Annex D (informative) Natural gas-based fuels for reciprocating internal combustion engines 44
Annex E (informative) Basis of the MN method . 45
C
Bibliography . 52

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© ISO 2025 – All rights reserved
iii
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Foreword
spacing: single
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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 193, Natural gas.
A list of all parts in the ISO 17507 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.
Formatted: Font: 10 pt
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iv © ISO 2024 2025 – All rights reserved
iv
ISO/FDIS 17507-1:2025(en)
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Line spacing: single
Introduction
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Formatted: Font: Bold, English (United Kingdom)
The globalization of the natural gas market and the drive towards sustainability are increasing the diversity
of the supply of gases to the natural gas infrastructure. For example, the introduction of regasified liquefied
natural gas (LNG) can result in higher fractions of non-methane hydrocarbons in the natural gas grid than the
traditionally distributed pipeline gases for which these hydrocarbons have been removed during processing.
Also, the drive towards sustainable gaseous fuels, such as hydrogen and gases derived from biomass, results
in the introduction of “new” gas compositions that contain components that do not occur in the traditional
natural gas supply. Consequently, the increasing variations in gas composition affect the knock resistance of
the gas when used as a fuel. This can affect the operational integrity of reciprocating internal combustion
engines.
For the efficient and safe operation of gas engines, it is of great importance to characterize the knock resistance
of gaseous fuels accurately. Engine knock is caused by the autoignition of unburned fuel mixture ahead of this
mixture being consumed by the propagating flame. Mild engine knock increases pollutant emissions
accompanied by gradual build-up of component damage and complete engine failure if not counteracted.
Severe knock causes structural damage to critical engine parts, which can quickly lead to catastrophic engine
failure. To ensure that gas engines are matched with the expected variations in fuel composition, the knock
resistance of the fuel is to be characterized, and subsequently specified, unambiguously.
Traditional methods for characterizing the knock resistance of gaseous fuels, such as the methane number
method developed by Anstalt für Verbrennungskraftmaschinen List (AVL) in the 1960s, relate the knock
propensity of a given fuel with that of an equivalent methane/hydrogen mixture using a standardized test
engine (see References [1], [2] and [3]). Several other methane number methods have since been developed,
sometimes based on either the approach or data, or both from the original experimental work performed by
AVL.
In recognition of the need to standardize a method for characterizing the knock resistance of gaseous fuels,
several existing methods for calculating a methane number have been considered, including the MN method
C
outlined in this document. ISO 17507-2 describes the PKI method.
Methods to calculate a methane number are based on the input of the gas composition under investigation.
While methods can be fundamentally different in their development approach, ideally the methods produce
similar methane numbers for the range of gas compositions they are valid for. Yet, differences in outcome can
be observed. Engine manufacturers typically determine the calculation method to be used when specifying a
methane number value for their engines as part of their application and warranty statements. In all cases,
when specifying a methane number based on either method, or any other method, the method used should be
noted.
The MN method is based on the original data of the research programprogramme performed by AVL
C
[1]
Deutschland (AVL is based in Graz, Austria) GmbH[1] for FVV (the Research Association for Combustion
[2] [3]
Engines). The methodology first proposed by Deutz (“Klöckner-Humboldt-Deutz AG”)[2],[3]”) , was later
amended in 2005 and 2011 by MWM (“Motoren-Werke Mannheim AG”). A more detailed history of the MN
C
method can be found in Annex E.Annex E.
The MN method takes the components of the gaseous fuel mixture and groups them together into several
C
ternary and binary groups whose methane number has been experimentally determined. It then determines
the overall methane number by applying optimization algorithms to the individual component groupings.
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© ISO 2025 – All rights reserved
v
Final Draft International Standard

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Natural gas — Calculation of methane number of gaseous fuels for 0 pt, Section start: New page, Header distance from
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reciprocating internal combustion engines — —
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Part 1: MNC
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MNc method
numbers
1 Scope
This document specifies the MNC method for the calculation of the methane number of a gaseous fuel, using
the composition of the gas as sole input for the calculation.
This document applies to natural gas (and biomethane) and their admixtures with hydrogen.
2 Normative references
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The following documents are referred to in the text in such a way that some or all of their content constitutes
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requirements of this document. For dated references, only the edition cited applies. For undated references,
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the latest edition of the referenced document (including any amendments) applies. stops: Not at 19.85 pt + 39.7 pt + 59.55 pt + 79.4 pt
+ 99.25 pt + 119.05 pt + 138.9 pt + 158.75 pt +
ISO 14532, Natural gas — Vocabulary 178.6 pt + 198.45 pt
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ISO 14912, Gas analysis — Conversion of gas mixture composition data
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ISO/IEC Guide 98-3, Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in
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measurement (GUM:1995)
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3 Terms and definitions
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For the purposes of this document, the terms and definitions given in ISO 14532 and the following apply. ISO
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and IEC maintain terminology databases for use in standardization at the following addresses:
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Fo
...

PROJET FINAL
Norme
internationale
ISO/TC 193
Gaz naturel — Calcul de l'indice de
Secrétariat: NEN
méthane des combustibles gazeux
Début de vote:
pour les moteurs alternatifs à
2025-08-01
combustion interne —
Vote clos le:
2025-09-26
Partie 1:
Méthode IMc
Natural gas — Calculation of methane number of gaseous fuels
for reciprocating internal combustion engines —
Part 1: MNc method
LES DESTINATAIRES DU PRÉSENT PROJET SONT
INVITÉS À PRÉSENTER, AVEC LEURS OBSERVATIONS,
NOTIFICATION DES DROITS DE PROPRIÉTÉ DONT ILS
AURAIENT ÉVENTUELLEMENT CONNAISSANCE ET À
FOURNIR UNE DOCUMENTATION EXPLICATIVE.
OUTRE LE FAIT D’ÊTRE EXAMINÉS POUR
ÉTABLIR S’ILS SONT ACCEPTABLES À DES FINS
INDUSTRIELLES, TECHNOLOGIQUES ET COM-MERCIALES,
AINSI QUE DU POINT DE VUE DES UTILISATEURS, LES
PROJETS DE NORMES
TRAITEMENT PARALLÈLE ISO/CEN
INTERNATIONALES DOIVENT PARFOIS ÊTRE CONSIDÉRÉS
DU POINT DE VUE DE LEUR POSSI BILITÉ DE DEVENIR DES
NORMES POUVANT
SERVIR DE RÉFÉRENCE DANS LA RÉGLEMENTATION
NATIONALE.
Numéro de référence
PROJET FINAL
Norme
internationale
ISO/TC 193
Gaz naturel — Calcul de l'indice de
Secrétariat: NEN
méthane des combustibles gazeux
Début de vote:
pour les moteurs alternatifs à
2025-08-01
combustion interne —
Vote clos le:
2025-09-26
Partie 1:
Méthode IMc
Natural gas — Calculation of methane number of gaseous fuels
for reciprocating internal combustion engines —
Part 1: MNc method
LES DESTINATAIRES DU PRÉSENT PROJET SONT
INVITÉS À PRÉSENTER, AVEC LEURS OBSERVATIONS,
NOTIFICATION DES DROITS DE PROPRIÉTÉ DONT ILS
AURAIENT ÉVENTUELLEMENT CONNAISSANCE ET À
FOURNIR UNE DOCUMENTATION EXPLICATIVE.
DOCUMENT PROTÉGÉ PAR COPYRIGHT
OUTRE LE FAIT D’ÊTRE EXAMINÉS POUR
ÉTABLIR S’ILS SONT ACCEPTABLES À DES FINS
© ISO 2025 INDUSTRIELLES, TECHNOLOGIQUES ET COM-MERCIALES,
AINSI QUE DU POINT DE VUE DES UTILISATEURS, LES
Tous droits réservés. Sauf prescription différente ou nécessité dans le contexte de sa mise en œuvre, aucune partie de cette
PROJETS DE NORMES
TRAITEMENT PARALLÈLE ISO/CEN
INTERNATIONALES DOIVENT PARFOIS ÊTRE CONSIDÉRÉS
publication ne peut être reproduite ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique,
DU POINT DE VUE DE LEUR POSSI BILITÉ DE DEVENIR DES
y compris la photocopie, ou la diffusion sur l’internet ou sur un intranet, sans autorisation écrite préalable. Une autorisation peut
NORMES POUVANT
être demandée à l’ISO à l’adresse ci-après ou au comité membre de l’ISO dans le pays du demandeur.
SERVIR DE RÉFÉRENCE DANS LA RÉGLEMENTATION
NATIONALE.
ISO copyright office
Case postale 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Genève
Tél.: [phone]
E-mail: [e-mail]
Web: www.iso.org
Publié en Suisse Numéro de référence
ii
Sommaire Page
Avant-propos .iv
Introduction .v
1 Domaine d'application . 1
2 Références normatives . 1
3 Termes et définitions . 1
4 Symboles et abréviations . 2
5 Méthode IMc . 2
5.1 Introduction .2
5.2 Applicabilité .2
5.2.1 Plage de composition normalisée du combustible gazeux .2
5.2.2 Manipulation d'autres constituants de combustible gazeux .4
5.3 Méthodologie de calcul de l'IMc.4
5.4 Expression des résultats . .5
5.5 Erreur d'incertitude et biais .5
6 Exemple de calculs . 5
6.1 Exemple 1 .5
6.1.1 Simplification de la composition du combustible gazeux .5
6.1.2 Sélection des systèmes ternaires .6
6.1.3 Subdivision du constituant exempt de gaz inertes en mélanges partiels
sélectionnés .9
6.1.4 Calcul de l'indice de méthane des mélanges partiels .9
6.1.5 Critères de non-utilisation des systèmes ternaires pour le calcul final de l'IMc .9
6.1.6 Ajustement de la composition et de la fraction des mélanges partiels .9
6.1.7 Calcul de l'indice de méthane du mélange simplifié .10
6.1.8 Calcul de l'indice de méthane du combustible gazeux .11
6.2 Exemple 2 .11
6.2.1 Simplification de la composition du combustible gazeux .11
6.2.2 Calcul de l'ajustement des systèmes ternaires .11
6.2.3 Sélection des mélanges ternaires .11
6.2.4 Calcul de l'indice de méthane . 12
6.3 Exemple 3 . 12
6.3.1 Simplification de la composition du combustible gazeux . 12
6.3.2 Calcul de l'ajustement des systèmes ternaires . 12
6.3.3 Sélection des mélanges ternaires . 12
6.3.4 Calcul de l'indice de méthane . 13
6.3.5 Exemples numériques supplémentaires. 13
Annexe A (normative) Résultats numériques des calculs pour diverses compositions à des fins
de validation de logiciel . . 14
Annexe B (informative) Outils destinés aux utilisateurs de la méthode IMc .29
Annexe C (normative) Erreur d'incertitude et biais .30
Annexe D (informative) Combustibles à base de gaz naturel pour les moteurs alternatifs à
combustion interne .32
Annexe E (informative) Base de la méthode IMc .33
Bibliographie .38

iii
Avant-propos
L'ISO (Organisation internationale de normalisation) est une fédération mondiale d'organismes nationaux
de normalisation (comités membres de l'ISO). L'élaboration des Normes internationales est en général
confiée aux comités techniques de l'ISO. Chaque comité membre intéressé par une étude a le droit de faire
partie du comité technique créé à cet effet. Les organisations internationales, gouvernementales et non
gouvernementales, en liaison avec l'ISO participent également aux travaux. L'ISO collabore étroitement avec
la Commission électrotechnique internationale (IEC) en ce qui concerne la normalisation électrotechnique.
Les procédures utilisées pour élaborer le présent document et celles destinées à sa mise à jour sont
décrites dans les Directives ISO/IEC, Partie 1. Il convient, en particulier, de prendre note des différents
critères d'approbation requis pour les différents types de documents ISO. Le présent document
a été rédigé conformément aux règles de rédaction données dans les Directives ISO/IEC, Partie 2
(voir www.iso.org/directives).
L'ISO attire l'attention sur le fait que la mise en application du présent document peut entraîner l'utilisation
d'un ou de plusieurs brevets. L'ISO ne prend pas position quant à la preuve, à la validité et à l'applicabilité
de tout droit de propriété revendiqué à cet égard. À la date de publication du présent document, l'ISO
n'avait pas reçu notification qu'un ou plusieurs brevets pouvaient être nécessaires à sa mise en application.
Toutefois, il y a lieu d'avertir les responsables de la mise en application du présent document que des
informations plus récentes sont susceptibles de figurer dans la base de données de brevets, disponible à
l'adresse www.iso.org/brevets. L'ISO ne saurait être tenue pour responsable de ne pas avoir identifié tout ou
partie de tels droits de brevet.
Les appellations commerciales éventuellement mentionnées dans le présent document sont données pour
information, par souci de commodité, à l'intention des utilisateurs et ne sauraient constituer un engagement.
Pour une explication de la nature volontaire des normes, la signification des termes et expressions
spécifiques de l'ISO liés à l'évaluation de la conformité, ou pour toute information au sujet de l'adhésion de
l'ISO aux principes de l'Organisation mondiale du commerce (OMC) concernant les obstacles techniques au
commerce (OTC), voir www.iso.org/avant-propos.
Le présent document a été élaboré par le comité technique ISO/TC 193, Gaz naturel.
Une liste de toutes les parties de la série ISO 17507 se trouve sur le site web de l'ISO.
Il convient que l'utilisateur adresse tout retour d'information ou toute question concernant le présent
document à l'organisme national de normalisation de son pays. Une liste exhaustive desdits organismes se
trouve à l’adresse www.iso.org/fr/members.html.

iv
Introduction
La mondialisation du marché du gaz naturel et la recherche de développement durable augmentent la diversité
en termes d'approvisionnement en gaz de l'infrastructure de gaz naturel. Par exemple, l'introduction de GNL
regazéifié peut entraîner des fractions plus élevées d'hydrocarbures non méthaniques dans le réseau de gaz
naturel que dans les gaz de canalisation traditionnellement distribués pour lesquels ces hydrocarbures ont
été éliminés pendant le traitement. De plus, la recherche d'introduction de combustibles gazeux durables tels
que l'hydrogène et les gaz dérivés de la biomasse conduit à l'introduction de «nouvelles» compositions du
gaz, contenant des constituants qui ne se trouvent pas dans l'approvisionnement traditionnel en gaz naturel.
Par conséquent, les variations croissantes de la composition du gaz ont une influence sur la résistance au
c
...