kSIST FprEN ISO 6338-5:2026

• Abstract:

  This document provides the part of the method to calculate the GHG emissions throughout the; LNG chain specific to regasification.; The general requirements are covered in ISO 6338-1.

• Status: Not Published
• Public Enquiry End Date: 01-May-2026
• ICS: 13.020.40 - Pollution, pollution control and conservation
• ICS: 75.020 - Extraction and processing of petroleum and natural gas
• Technical Committee: DPL - Gas supply
• Current Stage: 5020 - Formal vote (FV) (Adopted Project)
• Start Date: 02-Nov-2026
• Due Date: 21-Dec-2026
• Ref Project: FprEN ISO 6338-5 - Calculations of greenhouse gas (GHG) emissions throughout the liquefied natural gas (LNG) chain - Part 5: Regasification (ISO/FDIS 6338-5:2026)

kSIST FprEN ISO 6338-5:2026 is the SIST version of ISO 6338-5 for calculating greenhouse gas (GHG) emissions throughout the liquefied natural gas (LNG) chain at the regasification stage. It specifies how to quantify emissions from the inlet to the outlet of a regasification plant, and it is used together with ISO 6338-1 for the general requirements.

What does kSIST FprEN ISO 6338-5:2026 specify?

kSIST FprEN ISO 6338-5:2026 specifies the regasification part of the LNG-chain GHG calculation method. It focuses on the facilities and activities at a regasification plant and sets the structure for how those emissions are reported.

The document is organized into Clauses 1 to 9, plus a bibliography. Clause 5 covers inventory boundaries, Clause 6 covers quantification of emissions, and Clauses 7 to 9 cover quality management, reporting, and independent review.

The scope includes regasification plant activities and associated facilities, while the document also states how some related activities are treated. This matters in practice because a plant operator needs to know which equipment, utilities, and downstream interfaces belong inside the inventory boundary.

What are the key requirements of kSIST FprEN ISO 6338-5:2026?

Inventory boundaries and reporting scope

Clause 5 requires the GHG report for LNG regasification to cover all associated facilities within the reporting boundary. The organization with financial and/or operational control over those facilities reports the GHG emissions and removals, at least on an annual average basis.

In practice, this means the inventory is not limited to the vaporization equipment alone. It also includes marine facilities, LNG storage, utilities, onsite power generation, imported utilities, and the regasification unit.

Clause 5 also treats injection into the gas grid as the responsibility of the plant operator. That point matters for allocating emissions to the correct operator and reporting line.

What is in scope at the regasification site

The document includes regasification-related facilities such as unloading arms, storage, pumps, vaporisers, boil-off gas system, metering, and a Floating Storage and Regasification Unit (FSRU). It also covers imported power and other utilities.

It places the LNG carrier, road and rail tanker loading, LNG distribution by road or rail, and gas transmission grid outside the regasification plant boundary. For a buyer or engineer, that helps separate site emissions from transport or downstream network emissions.

How emissions are quantified

Clause 6 says the general approach comes from ISO 6338-1, then breaks the regasification site into source categories. It covers fuel combustion, flaring and venting, fugitive emissions, and emissions linked to imported energy, utilities, and consumables.

For combustion sources, the document expects primary data where possible, especially fuel consumption and fuel composition. In practice, operators need measured fuel data for major users and a justified estimate where direct measurement is not available.

For flaring and venting, the standard distinguishes between larger events and smaller routine sources. Unburned hydrocarbons, such as methane slip, are to be taken into account across the sections, so operators need to include those losses in their calculations.

For fugitive emissions, the document points to equipment counts, standard leakage factors, and measured atmospheric monitoring data where available. That helps an operator choose between default factors and site-specific measurements.

Imported energy and consumables

Clause 6.2.5 requires supplier data for imported energy, utilities, and consumables. If reliable GHG data for imports are not available, the full supply chain for the imported commodity is counted, and cut-off criteria follow ISO 14044.

This matters because regasification plants often depend on imported electricity, heat, nitrogen, air, water, or refrigerants. The standard tells the user to trace those indirect emissions back to the supplier or upstream chain.

Allocation, quality, reporting, and review

Clause 6.5 says emissions from regasification processes are allocated to the energy forms used and produced, such as heat, cold, and electricity. If products or services are sold downstream, allocation methods must be defined using energy or mass basis.

Clauses 7, 8, and 9 direct the user back to ISO 6338-1 for inventory quality management, reporting, and independent review. In practice, the regasification-specific part is paired with the general series requirements for final inventory handling.

What terms does kSIST FprEN ISO 6338-5:2026 define?

• GHG - greenhouse gas, the emissions family being quantified across the LNG chain.
• LNG - liquefied natural gas, the product whose chain includes regasification.
• FSRU - Floating Storage and Regasification Unit, a floating regasification installation mentioned in the scope.
• BOG - boil-off gas, gas generated from LNG storage and handled in the regasification process.
• NRU - nitrogen rejection unit, a unit that can generate nitrogen vents containing methane.
• Allocation - the method of assigning emissions to outputs such as heat, cold, or electricity.

Who uses kSIST FprEN ISO 6338-5:2026?

kSIST FprEN ISO 6338-5:2026 is used by LNG terminal operators, regasification plant managers, GHG inventory teams, auditors, and environmental or sustainability staff. It is also relevant to buyers and engineers who need a defensible method for quantifying site emissions.

The document is useful for operational control teams that collect fuel, flare, vent, utility, and metering data. It also supports independent review and reporting work where the inventory boundary has to be clearly defined.

Which standards are used with kSIST FprEN ISO 6338-5:2026?

ISO 6338-1 provides the general requirements, principles, calculation approach, preferred units, allocation principles, quality management, reporting, and independent review used by this part. It is the main companion document.

ISO 14044 provides environmental management and life cycle assessment requirements and is used here for cut-off criteria when imported data are not reliable. ISO 14064-1 provides GHG quantification and reporting terminology and framework at the organization level.

ISO 20257-1 and ISO 20257-2 are mentioned for information on FSRU design and related issues.

What does the kSIST FprEN ISO 6338-5:2026 document contain?

The document contains one typical regasification plant figure, a facility boundary table, and several source-category tables for quantification. It also gives the structure for handling combustion, flaring and venting, fugitive emissions, and imported energy or consumables.

Its technical content is organized around practical calculation methods rather than worked examples. For users, that means the document is meant to support inventory design, data collection, emission calculation, reporting, and review for regasification sites.

SLOVENSKI STANDARD
oSIST prEN ISO 6338-5:2026
01-april-2026
Izračuni emisij toplogrednih plinov v oskrbovalni verigi z utekočinjenim
zemeljskim plinom (LNG) - 5. del: Ponovno uplinjanje (ISO/DIS 6338-5:2026)
Calculations of greenhouse gas (GHG) emissions throughout the liquefied natural gas
(LNG) chain - Part 5: Regasification (ISO/DIS 6338-5:2026)
Berechnungsverfahren der Treibhausgasemissionen (THG) in der gesamten
Flüssigerdgas-(LNG-)Kette - Teil 5: Wiederverdampfung (ISO/DIS 6338-5:2026)
Calcul des émissions de gaz à effet de serre (GES) dans la chaîne gaz naturel liquéfié
(GNL) - Partie 5: Regazéification (ISO/DIS 6338-5:2026)
Ta slovenski standard je istoveten z: prEN ISO 6338-5
ICS:
13.020.40 Onesnaževanje, nadzor nad Pollution, pollution control
onesnaževanjem in and conservation
ohranjanje
75.020 Pridobivanje in predelava Extraction and processing of
nafte in zemeljskega plina petroleum and natural gas
oSIST prEN ISO 6338-5:2026 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN ISO 6338-5:2026
oSIST prEN ISO 6338-5:2026
DRAFT
International
Standard
ISO/DIS 6338-5
ISO/TC 67/SC 9
Calculations of greenhouse gas
Secretariat: AFNOR
(GHG) emissions throughout the
Voting begins on:
liquefied natural gas (LNG) chain —
2026-02-09
Part 5:
Voting terminates on:
2026-05-04
Regasification
Calcul des émissions de gaz à effet de serre (GES) dans la chaîne
gaz naturel liquéfié (GNL) —
Partie 5: Regazéification
ICS: 13.020.40; 75.020
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
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.
Reference number
ISO/DIS 6338-5:2026(en)
oSIST prEN ISO 6338-5:2026
DRAFT
ISO/DIS 6338-5:2026(en)
International
Standard
ISO/DIS 6338-5
ISO/TC 67/SC 9
Calculations of greenhouse gas
Secretariat: AFNOR
(GHG) emissions throughout the
Voting begins on:
liquefied natural gas (LNG) chain —
Part 5:
Voting terminates on:
Regasification
Calcul des émissions de gaz à effet de serre (GES) dans la chaîne
gaz naturel liquéfié (GNL) —
Partie 5: Regazéification
ICS: 13.020.40; 75.020
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2026
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
BE CONSIDERED IN THE LIGHT OF THEIR
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
or ISO’s member body in the country of the requester.
NATIONAL REGULATIONS.
ISO copyright office
RECIPIENTS OF THIS DRAFT ARE INVITED
CP 401 • Ch. de Blandonnet 8
TO SUBMIT, WITH THEIR COMMENTS,
CH-1214 Vernier, Geneva
NOTIFICATION OF ANY RELEVANT PATENT
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RIGHTS OF WHICH THEY ARE AWARE AND TO
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Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ISO/DIS 6338-5:2026(en)
ii
oSIST prEN ISO 6338-5:2026
ISO/DIS 6338-5:2026(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principles . 1
5 GHG inventory boundaries . 1
6 Quantification of GHG emissions . 2
6.1 General .2
6.2 Identification of GHG sources and quantification approach .3
6.2.1 General .3
6.2.2 Emissions from fuel combustion . .3
6.2.3 Emissions from flaring and venting .4
6.2.4 Fugitive emissions .4
6.2.5 Emissions associated with imported energy, utilities, and consumables .5
6.3 Calculation of GHG emissions .5
6.4 Preferred units .5
6.5 Allocation .6
6.6 Carbon capture .6
7 GHG inventory quality management . 6
8 GHG reporting . 6
9 Independent review . . 6
Bibliography . 7

iii
oSIST prEN ISO 6338-5:2026
ISO/DIS 6338-5:2026(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
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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 67, Oil and gas industries including lower carbon
energy, Subcommittee SC 9, Production, transport and storage facilities for cryogenic liquefied gases.
A list of all parts in the ISO 6338 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
oSIST prEN ISO 6338-5:2026
ISO/DIS 6338-5:2026(en)
Introduction
Natural gas will play a key role in the energy transition (e.g. by replacing coal to produce electricity) and the
use of liquefied natural gas (LNG) to transport natural gas is expected to increase. The process of liquefying
natural gas is energy-intensive. Gas producers are increasingly accountable for their greenhouse gas (GHG)
emissions and the ambition to reduce them. Furthermore, there is an emerging marketing demand for GHG
data to enable commercial mechanisms such as offsetting to be utilized.
There is no standardized and auditable methodology to calculate the carbon footprint of the whole LNG
chain (including but not limited to the well, upstream treatment, transportation, liquefaction, shipping,
regasification and end user distribution). Various standards indicate possible approaches but are
inconsistent in their results or not easily applicable.
The ISO 6338 series covers each part of the LNG chain and enables a consistent GHG inventory.
The KPIs and related requirements to access to key international initiatives, agreements and reporting/
accounting standards on climate ambitions and zero carbon emission strategies are given in ISO 6338-1:2024,
Annex B.
Attention should be paid to activities that can occur in different parts (e.g. gas treatment and distribution
upstream of the liquefaction plant).
NOTE It is not possible to make like-for-like comparisons, or define a certification scheme, for one block only.

v
oSIST prEN ISO 6338-5:2026
oSIST prEN ISO 6338-5:2026
DRAFT International Standard ISO/DIS 6338-5:2026(en)
Calculations of greenhouse gas (GHG) emissions throughout
the liquefied natural gas (LNG) chain —
Part 5:
Regasificatio
...