prEN ISO 19870-1

SLOVENSKI STANDARD
01-junij-2025
[Not translated]
Hydrogen technologies - Methodology for determining the greenhouse gas emissions
associated with the hydrogen supply chain - Part 1: Emissions associated with the
production of hydrogen to production gate (ISO/DIS 19870-1:2025)
Technologies de l'hydrogène - Méthodologie pour déterminer les émissions de gaz à
effet de serre associées à la chaîne d'approvisionnement en hydrogène - Partie 1:
Émissions associées à la production d'hydrogène jusqu'au point de production (ISO/DIS
19870-1:2025)
Ta slovenski standard je istoveten z: prEN ISO 19870-1
ICS:
13.020.40 Onesnaževanje, nadzor nad Pollution, pollution control
onesnaževanjem in and conservation
ohranjanje
27.075 Tehnologija vodika Hydrogen technologies
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
International
Standard
ISO/DIS 19870-1
ISO/TC 197/SC 1
Hydrogen technologies —
Secretariat: SCC
Methodology for determining
Voting begins on:
the greenhouse gas emissions
2025-05-05
associated with the hydrogen
Voting terminates on:
supply chain —
2025-07-28
Part 1:
Emissions associated with
the production of hydrogen to
production gate
ICS: 27.075; 13.020.40
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FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
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Reference number
ISO/DIS 19870-1:2025(en)
DRAFT
ISO/DIS 19870-1:2025(en)
International
Standard
ISO/DIS 19870-1
ISO/TC 197/SC 1
Hydrogen technologies —
Secretariat: SCC
Methodology for determining
Voting begins on:
the greenhouse gas emissions
associated with the hydrogen
Voting terminates on:
supply chain —
Part 1:
Emissions associated with
the production of hydrogen to
production gate
ICS: 27.075; 13.020.40
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 2025
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
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Published in Switzerland Reference number
ISO/DIS 19870-1:2025(en)
ii
ISO/DIS 19870-1:2025(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and abbreviated terms . 2
3.1 Quantification of the Carbon Footprint of a Product .2
3.2 Products, product systems and processes .4
3.3 Life Cycle Assessment .8
3.4 Organizations .11
3.5 Data and Data Quality .11
3.6 Abbreviated Terms . 12
4 Evaluation Methods .12
4.1 Evaluation Basis . 12
4.1.1 General Principles . 12
4.1.2 Attributional approach . 13
4.1.3 Consequential approach . 13
4.2 Product reporting .14
4.2.1 Product System Boundary .14
4.2.2 Selected Cut-Off Criteria . 15
4.2.3 Evaluation Elements . 15
4.2.4 Evaluation cycle .16
4.3 Quantification of GHG emissions .16
4.3.1 Process description and data quality .16
4.3.2 Emissions inventory .17
4.3.3 Emissions allocation . 22
4.4 CFP study report . 26
5 Critical review .26
Annex A (Normative) Hydrogen Purity .27
Annex B (informative) Consequential Approach—Examples for Hydrogen Production .31
Annex C  Feedstocks for Hydrogen Production .35
Annex D  Hydrogen Production Pathway – Methane Reforming (with or without Carbon Capture
and Storage) .42
Annex E  Hydrogen Production Pathway – Water Electrolysis .58
Annex F  Hydrogen Production Pathway – Chlor-alkali .63
Annex G  Hydrogen Production Pathway – Steam cracking .70
Annex H Hydrogen Production Pathway – Gasification with or without carbon capture .77
Annex I  Hydrogen Production Pathway – Methane pyrolysis .85
Annex J  Hydrogen Production Pathway – Chemical Looping Water Splitting with or without
carbon capture .93
Annex K  Hydrogen Production Pathway – Geologic Hydrogen Production .100
Annex L  Hydrogen Production Pathway – Catalytic Naphtha Reforming .110
Bibliography .116

iii
ISO/DIS 19870-1:2025(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 197, Hydrogen technologies, Subcommittee SC
1, Hydrogen at scale and horizontal energy systems.
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/DIS 19870-1:2025(en)
Introduction
The Paris Agreement was adopted at the UN Climate Change conference (COP21) with the aims of:
strengthening the global response to the threat of climate change, restricting global temperature rise to
below 2 °C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1,5 °C above
pre-industrial levels. To meet these goals, greenhouse gas (GHG) emissions need to be reduced by about
45 % from 2010 levels by 2030, reaching net zero in 2050 (IPCC, 2018; UNFCCC, 2021).
GHG initiatives on mitigation rely on the quantification, monitoring, reporting and verification of GHG
emissions and/or removals. International Standards that support the transformation of scientific knowledge
into tools can help in reaching the targets of the Paris Agreement to address climate change.
ISO 14044 defines the requirements and guidelines identified in existing International Standards on life
cycle assessment (LCA). The ISO 14060 series provides clarity and consistency for quantifying, monitoring,
reporting and validating or verifying GHG emissions and removals to support sustainable development
through a low-carbon economy. It also benefits organizations, project proponents and stakeholders
worldwide by providing clarity and consistency on quantifying, monitoring, reporting and validating or
verifying GHG emissions and removals.
ISO 14067 is based on the requirements and guidelines on LCA identified in ISO 14044 and aims to set
specific requirements for the quantification of a carbon footprint (CFP) and a partial CFP. ISO 14067 defines
the principles, requirements and guidelines for the quantification of the carbon footprint of products. Its
aim is to quantify GHG emissions associated with the lifecycle stages of a product, beginning with resource
extraction and raw material sourcing and extending through the production, use and end-of-life stages of
the product.
Figure 1 illustrates the relationship between ISO 14067 and other ISO documents on LCA.
PCR: Product category rule
Figure 1 — Relationship between standards beyond the GHG management family of standards
(source ISO 14067:2018)
Hydrogen can be produced from diverse sources including renewables, nuclear and fossil fuels, with or
without carbon capture, utilization and storage (CCUS). Hydrogen can be used to decarbonize numerous
sectors.
A particular challenge is that identical hydrogen molecules can be produced and combined from sources
that have different GHG intensities. Similarly, hydrogen-based fuels and derivatives will be indistinguishable
and can be produced from hydrogen combined with a range of fossil and low-carbon inputs. Indeed,

v
ISO/DIS 19870-1:2025(en)
some of the products made from hydrogen (e.g. electricity) can themselves be used in the production of
hydrogen. Accounting standards for different sources of hydrogen along the supply chain (see Figure 2) will
be fundamental to create a market for low-carbon hydrogen, and these standards need to be agreed upon
internationally. Additionally, there is the possibility that consumption gates are not located in proximity to
hydrogen production gates, requiring hydrogen transport. ISO 14083 gives guidelines for the quantification
and reporting of GHG emissions arising from transport chain operations.
A mutually recognized international framework that is robust, and that avoids miscounting or double
counting of environmental impacts is needed. Such a framework will provide a mutually agreed upon
approach to “guarantees" or “certificates” of origin, and will cover greenhouse gas inputs used for hydrogen
production, conditioning, conversion and transport.
The series of international standards ISO 19870 aims at establishing methodologies that should be applied, in
line with ISO 14067, to the specific case of the hydrogen value chain, covering different production processes
and other parts of the value chain, such as conditioning hydrogen in different physical states, conversion of
hydrogen into different hydrogen carriers and the subsequent transport up to the consumption gate. This
document, ISO 19870-1 considers the steps up to the production gate.
Figure 2 — Examples of hydrogen supply chain

vi
DRAFT International Standard ISO/DIS 19870-1:2025(en)
Hydrogen technologies — Methodology for determining the
greenhouse gas emissions associated with the hydrogen
supply chain —
Part 1:
Emissions associated with the production of hydrogen to
production gate
1 Scope
ISO 14044 requires the goal and scope of an LCA to be clearly defined and be consistent with the intended
application. Due to the iterative nature of LCAs, it is possible that the LCA scope needs to be refined during
the study.
The goals and scopes of the methodologies correspond to either approach a) or b), given below, that
ISO 14040:2006, Annex A2 gives as two possible approaches to LCAs.
a) An approach that assigns elementary flows and potential environmental impacts to a specific product
system, typically as an account of the history of the product. See Section 4.1.2.
b) An approach that studies the environmental consequences of possible (future) changes between
alternative product systems. See Section 4.1.3.
In this document, approach (a) is referred to as an attributional approach, while approach (b) is referred to
[1]
as a consequential approach. Complementary information is accessible in the ILCD handbook .
A Carbon Footprint of a Product (3.1.2) or Partial Carbon Footprint of a Product (3.1.3) as defined by
ISO 14067 may be estimated using either the attributional or the consequential approach, the latter
corresponding to the use of “system expansion via substitution” to avoid allocation when a unit process
yields multiple co-products. This document applies to the CFP for hydrogen production.
There are numerous pathways to produce hydrogen. This document describes in the annexes the
requirements and evaluation methods applied to several hydrogen production pathways of interest.
This document considers the GHG emissions associated with hydrogen production up to the production gate.
This document applies to and includes every steps within the production process up to the production gate
(see Figure 2 in the Introduction).
Complementary documents in the ISO 19870-X series will consider hydrogen conditioning, conversion and
transport methods.
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 14040:2006, Environmental management — Life cycle assessment — Principles and framework
ISO 14044, Environmental management — Life cycle assessment — Requirements and guidelines

ISO/DIS 19870-1:2025(en)
ISO 14067:2018, Greenhouse gases — Carbon footprint of products — Requirements and guidelines for
quantification
ISO 14083:2023, Greenhouse gases — Quantification and reporting of greenhouse gas emissions arising from
transport chain operations
ISO/TS 14071, Environmental management — Life cycle assessment — Critical review processes and reviewer
competencies: Additional requirements and guidelines to ISO 14044:2006
3 Terms, definitions and abbreviated terms
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1 Quantification of the Carbon Footprint of a Product
3.1.1
allocation
partitioning the input (3.2.8) or output (3.2.10) flows of a process or a product system (3.2.3) between the
product system under study and one or more other product systems
[SOURCE: ISO 14040:2006 and ISO 14040:2006/AMD 1:2020]
3.1.2
carbon footprint of a product
CFP
sum of greenhouse gas emissions (3.1.12) and greenhouse gas removals (3.1.4) in a product system (3.2.3),
expressed as CO equivalent (3.1.10) and based on a life cycle assessment (3.4.5) using the single impact
category of climate change
Note 1 to entry: A CFP can be disaggregated into a set of figures identifying specific GHG emissions (3.1.12) and
removals (3.1.4). A CFP can also be disaggregated into the stages of the life cycle (3.4.4) .
Note 2 to entry: The results of the quantification of CFP (3.1.8) are documented in the CFP study report expressed in
mass of CO e (3.1.11) per functional unit (3.2.14).
[SOURCE: ISO 14067:2018, 3.1.1.1]
3.1.3
partial CFP
sum of greenhouse gas emissions (3.1.12) and greenhouse gas removals (3.1.4) of one or more selected
process(es) in a product system (3.2.3) expressed as CO equivalents (3.1.10) and based on the selected stages
or processes within the life cycle (3.4.4)
Note 1 to entry: A partial CFP is based on or compiled from data related to (a) specific process(es) or footprint
information modules (defined in ISO 14026:2017, 3.1.4), which is (are) part of a product system (3.2.3) and can form the
basis for quantification of a carbon footprint of a product (CFP). More detailed information on information modules is
given in ISO 14025:2006, 5.4.
Note 2 to entry: The results of the quantification of the partial CFP are documented in the CFP study report expressed
in mass of CO e (3.1.10) per declared unit.
Note 3 to entry: In this document, partial CFP of hydrogen is extends from raw material extraction up to the
production gate.
ISO/DIS 19870-1:2025(en)
3.1.4
greenhouse gas removal
GHG removal
withdrawal of a greenhouse gas (3.1.9) from the atmosphere
[SOURCE: ISO 14067:2018, 3.1.2.6]
3.1.5
CFP study
all activities that are necessary to quantify and report the carbon footprint of a product (3.1.2) or a partial
CFP (3.1.3)
[SOURCE: ISO 14067:2018, 3.1.1.4]
3.1.6
product category
group of products that can fulfil equivalent functions
[SOURCE: ISO 14025:2006, 3.12]
3.1.7
production batch
amount of products produced by a device between any two points in time selected by the operator
3.1.8
quantification of CFP
activities that result in the determination of the carbon footprint of a product (3.1.2) or a partial CFP (3.1.3)
Note 1 to entry: Quantification of the carbon footprint of a product (3.1.2) or the partial CFP (3.1.3) is part of the CFP
study (3.1.5)
[SOURCE: ISO 14067:2018, 3.1.1.6]
3.1.9
greenhouse gas
GHG
gaseous constituent of the atmosphere, both natural and anthropogenic, that absorbs and emits radiation
at specific wavelengths within the spectrum of infrared radiation emitted by the Earth’s surface, the
atmosphere and clouds
Note 1 to entry: For a list of greenhouse gases (3.1.9), see the latest IPCC Assessment Report.
Note 2 to entry: Water vapour and ozone, which are anthropogenic as well as natural greenhouse gases (3.1.9), are not
included in the carbon footprint of a product (3.1.2).
Note 3 to entry: The focus of this document is limited to long-lived GHGs and it therefore excludes climate effects due
to changes in surface reflectivity (albedo) and short-lived radiative forcing agents (e.g. black carbon and aerosols).
[SOURCE: ISO 14067:2018, 3.1.2.1]
3.1.10
carbon dioxide equivalent
CO equivalent
CO e
unit for comparing the radiative forcing of a greenhouse gas (3.1.9) to that of carbon dioxide
Note 1 to entry: Mass of a greenhouse gas is converted into CO equivalents by multiplying the mass of the greenhouse gas
(3.1.9) by the corresponding global warming potential (3.1.11) or global temperature change potential (GTP) of that gas.
Note 2 to entry: In the case of GTP, CO equivalent is the unit for comparing the change in global mean surface
temperature caused by a greenhouse gas to the temperature change caused by carbon dioxide.
[SOURCE: ISO 14067:2018, 3.1.2.2]

ISO/DIS 19870-1:2025(en)
3.1.11
global warming potential
GWP
index, based on radiative properties of greenhouse gases (3.1.9) (GHG) measuring the radiative forcing
following a pulse emission of a unit mass of a given GHG in the present-day atmosphere integrated over a
chosen time horizon, relative to that of carbon dioxide (CO )
Note 1 to entry: “Index” as used in this document is a “characterization factor” as defined in ISO 14040:2006, 3.37.
Note 2 to entry: A “pulse emission” is an emission at one point in time.
[SOURCE: ISO 14067:2018, 3.1.2.4]
3.1.12
greenhouse gas emission
GHG emission
release of a greenhouse gas (3.1.9) into the atmosphere
[SOURCE: ISO 14067:2018, 3.1.2.5]
3.1.13
greenhouse gas emission factor
GHG emission factor
coefficient relating activity data with the greenhouse gas emission (3.1.3)
[SOURCE: ISO 14067:2018, 3.1.2.7]
3.1.14
capital goods emission
CAPEX emission
GHG emissions (3.1.12) related to the manufacturing of capital goods
3.1.15
subdivision
virtual subdivision
decomposition of a unit process into physically or virtually distinguishable sub-process steps with the
possibility to collect data exclusively for those sub-processes
3.1.16
hydrogen
gas mainly composed of hydrogen molecules.
Note 1 to entry: hydrogen molecule is referred as H .
3.1.17
physical relationship
relation between co-products (3.2.4) based on a chosen physical characteristic (e.g., mass, energy content,
volume). A physical relationship can be used (1) to allocate input flows to co-products (3.2.4) based on the
specific function the inputs perform in relation to the individual co-products (3.2.4) and/or (2) to allocate
GHG emissions (3.1.12) to the individual co-products (3.2.4)
3.2 Products, product systems and processes
3.2.1
product
any goods or service
Note 1 to entry: The product can be categorized as follows:
— services (e.g. transport);
— software (e.g. computer program, dictionary);

ISO/DIS 19870-1:2025(en)
— hardware (e.g. engine mechanical part);
— processed materials (e.g. lubricant).
[SOURCE: ISO 14040:2006, 3.9]
3.2.2
product flow
products (3.2.1) entering from or leaving to another product system (3.2.3)
[SOURCE: ISO 14040:2006, 3.27]
3.2.3
product system
collection of unit processes with elementary flows (3.2.16) and product flows (3.2.2), performing one or more
defined functions and which models the life cycle (3.4.4) of a product (3.2.1)
[SOURCE: ISO 14044:2006, 3.28]
3.2.4
co-product
one of two or more products (3.2.1) coming from the same unit process or product system (3.2.3) that is not
considered waste (3.3.15)
[SOURCE: modified from ISO 14040:2006, 3.10]
3.2.5
conditioning
means changing the physical conditions (e.g. temperature, pressure) of hydrogen for the purpose of its
storage or transport
Note 1 to entry: In this document, examples are changing the pressure of gaseous hydrogen or liquefying gaseous
hydrogen.
3.2.6
conversion
means changing the chemical conditions of a chemical species
3.2.7
heating value
amount of energy released when a fuel is burned completely
Note 1 to entry: Care must be taken not to confuse higher heating values (HHVs) and lower heating values (LHVs).
3.2.8
input
product (3.2.1), material or energy flow (3.2.17) that enters a unit process
Note 1 to entry: Products (3.2.1) and materials include raw materials, intermediate products (3.2.9) and co-products
(3.2.4).
[SOURCE: ISO 14040:2006, 3.21]
3.2.9
intermediate product
output from a unit process that is input to other unit processes that requires further transformation within
the system
[SOURCE: ISO 14040:2006, 3.23]

ISO/DIS 19870-1:2025(en)
3.2.10
output
product (3.2.1), material or energy flow (3.2.17) that leaves a unit process (3.2.13)
Note 1 to entry: Products (3.2.1), and materials include raw materials, intermediate products (3.2.9), co-products (3.2.4)
and releases (3.4.11) .
[SOURCE: ISO 14040:2006, 3.25]
3.2.11
system boundary
boundary based on a set of criteria representing which unit processes (3.2.13) are a part of the system
under study
[SOURCE: ISO 14040:2006/AMD 1:2020, 3.32]
3.2.12
system expansion
concept of expanding the product system (3.2.3) to include additional functions related to the co-products (3.2.4)
Note 1 to entry: The product system (3.2.3) that is substituted by the co-product (3.2.4) is integrated in the product
system (3.2.3) under study. In practice, the co-products (3.2.4) are compared to other substitutable products, and the
environmental burdens associated with the substituted product(s) are subtracted from the product system (3.2.3)
under study. The identification of this substituted system is done in the same way as the identification of the upstream
system for intermediate product (3.2.9) inputs (3.2.8). See also ISO/TR 14049:2012, 6.4
Note 2 to entry: The application of system expansion (3.2.12) involves an understanding of the market for the co-
products (3.2.4). Decisions about system expansion (3.2.12) can be improved through understanding the way co-
products (3.2.4) compete with other products, as well as the effects of any product substitution upon production
practices in the industries impacted by the co-products (3.2.4).
Note 3 to entry: Can be referred to as system expansion (3.2.12) and also as expanding the system boundary (3.2.11).
[SOURCE: ISO 14044:2006/AMD 2:2020, D.2.1]
3.2.13
process
set of interrelated or interacting activities that transforms inputs (3.2.8) into outputs (3.2.10)
[SOURCE: ISO 14044:2006, 3.11]
3.2.14
functional unit
quantified performance of a product system (3.2.3) for use as a reference unit
Note 1 to entry: As the carbon footprint of a product treats information on a product basis, an additional calculation
based on a declared unit can be presented.
[SOURCE: ISO 14040:2006, 3.20]
3.2.15
elementary flow
material or energy entering the system being studied that has been drawn from the environment without
previous human transformation, or material or energy leaving the system being studied that is released into
the environment without subsequent human transformation
Note 1 to entry: “Environment” is defined in ISO 14001:2015, 3.2.1.
[SOURCE: ISO 14044:2006, 3.12]

ISO/DIS 19870-1:2025(en)
3.2.16
energy flow
input (3.2.8) to or output (3.2.10) from a unit process or product system (3.2.3), quantified in energy units
Note 1 to entry: Energy flow that is an input can be called an energy input; energy flow that is an output can be called
an energy output.
[SOURCE: ISO 14040:2006, 3.13]
3.2.17
feedstock
any material input to the hydrogen plant that is not generated at the hydrogen plant itself. A non-exhaustive
list may include
— Natural gas (e.g. for steam methane reforming)
1)
— Biomethane/Renewable Natural Gas (e.g. for steam methane reforming)
—
— Biomass
— Coal (e.g. for gasification)
— Liquid Hydrocarbons (e.g. for catalytic reforming of naphtha)
— Biogenic Waste (e.g. for gasification)
— Non-biogenic Waste (e.g. for gasification)
— Oxygen (e.g. for autothermal reforming)
— Water (e.g. for water electrolysis)
— Steam
If a hydrogen plant both generates and utilizes a material (e.g. steam), only the portion that is received by
the hydrogen plant from an external source is considered to be a feedstock. For example, steam generated
within the hydrogen plant system boundary for use at the hydrogen plant is not considered to be a feedstock.
3.2.18
production gate
location of the end-outlet of the metered product (3.2.1) that leaves the product’s production system
boundary
3.2.19
delivery gate
any location where the product (3.2.1) is transferred from one operator to another
3.2.20
consumption gate
location of the final delivery of the product (3.2.1) to its end-use
1) In many European countries, methane sourced from the degradation of biomass under anaerobic conditions is
referred to as “biomethane”. In the United States, it is referred to as “Renewable Natural Gas” or “RNG”.

ISO/DIS 19870-1:2025(en)
3.3 Life Cycle Assessment
3.3.1
cut-off criteria
specification of the amount of material or energy flow (3.2.17) or the level of significance of greenhouse gas
emissions (3.1.12) associated with unit processes or the product system (3.2.3) to be excluded from a CFP
study (3.1.5)
[SOURCE: modified from ISO 14067:2018, 3.1.4.1]
3.3.2
evaluation
element within the life cycle interpretation phase intended to establish confidence in the results of the life
cycle assessment (3.3.5)
Note 1 to entry: Evaluation includes completeness check, sensitivity check, consistency check, and any other validation
that may be required according to the goal and scope definition of the study
[SOURCE: ISO 14040:2006]
3.3.3
fugitive emissions
emissions that are not physically controlled but result from the intentional or unintentional releases (3.3.10)
of GHGs (3.1.9)
Note 1 to entry: They commonly arise from the production, processing, transmission, storage, and use of fuels and
other chemicals, often through joints, seals, packing, gaskets, etc.
[SOURCE: 2004 GHG protocol, Chapter 4.6]
3.3.4
life cycle
consecutive and interlinked stages related to a product (3.2.1), from raw material acquisition or generation
from natural resources to end-of-life treatment
Note 1 to entry: “Raw material” is defined in ISO 14040:2006, 3.15.
Note 2 to entry: Stages of a life cycle related to a product include raw material acquisition, production, distribution,
use and end-of-life treatment.
[SOURCE: ISO 14067:2018, 3.1.4.2]
3.3.5
life cycle assessment
LCA
compilation and evaluation of the inputs (3.2.8), outputs (3.2.10) and the potential environmental impacts of
a product (3.2.1) throughout its life cycle (3.3.4)
Note 1 to entry: “Environmental impact” is defined in ISO 14001:2015, 3.2.4.
[SOURCE: modified from ISO 14067:2018, 3.1.4.3]
3.3.6
life cycle inventory analysis
LCI
phase of life cycle assessment (3.3.5) involving the compilation and quantification of inputs (3.2.8) and outputs
(3.2.10) for a product throughout its life cycle (3.3.4)
[SOURCE: ISO 14044:2006, 3.3]
ISO/DIS 19870-1:2025(en)
3.3.7
location-based method
uses the average emissions intensity of networks supplying energy commodities for consumption, such as
electricity, using mostly grid-average emission factors in the location in which energy consumption occurs.
[SOURCE: modified from ISO 14064-1:2018, Annex E]
3.3.8
market-based method
a method to assign the attributes of the product (3.2.1) produced by a specific producer to the product (3.2.1)
consumed by or delivered to a specific user while the product (3.2.1) is physically distributed through a
common infrastructure.
Note 1 to entry: These choices (purchasing energy certificates or differentiated electricity product) may be reflected
through contractual arrangements between the user and the producer.
3.3.9
process emissions
direct emissions within the system boundary, including emissions associated with waste treatment and
disposal, such as, but not limited to, chemical conversions and combustion of solid, liquid and/or gaseous
fuels or feedstock’s
3.3.10
releases
emissions to air and discharges to water and soil
[SOURCE: ISO 14040:2006, 3.30]
3.3.11
sensitivity analysis
systematic procedures for estimating the effects of the choices made regarding methods and data on the
outcome of a CFP study (3.1.5)
[SOURCE: ISO 14067:2018, 3.1.4.7]
3.3.12
sensitivity check
process to determine whether the information obtained from a sensitivity analysis (3.3.11) is relevant for
reaching the conclusions and for giving recommendations
[SOURCE: ISO 14040:2006/AMD1:2020, 3.43]
3.3.13
transparency
open, comprehensive and understandable presentation of information
[SOURCE: ISO 14040:2006, 3.7]
3.3.14
uncertainty analysis
systematic procedure to quantify the uncertainty introduced in the results of a life cycle inventory analysis
(3.3.6) due to the cumulative effects of model imprecision, input uncertainty and data variability
Note 1 to entry: Either ranges or probability distributions are used to determine uncertainty in the results.
[SOURCE: ISO 14040:2006, 3.33]
3.3.15
waste
substances or objects that the holder intends or is required to dispose of
Note 1 to entry: This definition is taken from the Basel Convention on the Control of Transboundary Movements of
Hazardous Wastes and Their Disposal (22 March 1989), but is not confined in this document to hazardous waste.

ISO/DIS 19870-1:2025(en)
[SOURCE: ISO 14040:2006, 3.35]
Note 2 to entry: Wastes potentially used as feedstocks for hydrogen production vary widely in composition and by
region. In this document, “waste” is defined as substances or objects that the holder intends or is required to dispose
of and that can be used as a feedstock for hydrogen production.
“Waste” is not necessarily a permanent designation for a material. If additional valorized product streams were to
emerge for a given type of material currently deemed a waste, then competition for its use as a feedstock for hydrogen
production might result in upstream emissions impacts.
To determine whether a feedstock is a waste, stakeholders should rely on analysis specific to the country the feedstock
was sourced from. Such analysis should account for the quantity of the respective feedstock that is available in the
host country, the approximate size of other markets for that feedstock, and the quantity of the feedstock expected to
be used for hydrogen production to determine whether valorization of the waste would have occurred otherwise.
3.3.16
biogenic waste
the biogenic portion of waste (3.3.15)
Note 1 to entry: A non-exhaustive list may include:
— The biogenic portion of municipal solid waste (MSW),
— Animal waste,
— Sewage sludge,
— Food industry residues,
— Agricultural residues,
— Food and agricultural waste (e.g., home food waste collection)
— Forests that would traditionally be left to decompose naturally (ICAO, 2019).
Whether a product (3.2.1) is considered a waste (3.3.15) or a valorized product (3.2.1) is based on the properties of
the material (e.g., corn stover versus corn kernel). A tree intended for timber harvest may be thinned because of
some perceived defect (e.g., a curved trunk, or relatively diminutive size relative to other trees in the stand). The
valorization of the “waste” material which could be considered “slash and thinning” may change the decision-making
of the forester regarding the disposition of woody material.
Ultimately, biomass suppliers should provide hydrogen producers with information establishing whether biomass
received as a feedstock (3.2.17) for hydrogen production is intentionally-produced biomass or biogenic waste. A
country’s legislations may encompass this definition.
3.3.17
non-biogenic waste
the non-biogenic portion of waste (3.3.15)
Note 1 to entry: Non-biogenic waste includes content of fossil origin which is not suitable for material recovery. A non-
exhaustive list may include:
— The non-biogenic portion of Municipal Solid Waste (MSW)
— The non-biogenic portion of Industrial Waste
— Plastic waste (3.3.15) of fossil origin (in some jurisdictions (e.g. Japan), this stream is considered to be a part of MSW)

ISO/DIS 19870-1:2025(en)
3.4 Organizations
3.4.1
organization
person or group of people that has its own functions with responsibilities, authorities and relationships to
achieve its objectives
Note 1 to entry: The concept of organization includes, but is not limited to, sole-trader, company, corporation, firm,
enterprise, authority, partnership, charity or institution, or part or combination thereof, whether incorporated or not,
public or private.
[SOURCE: ISO 14001:2015, Clause 4]
3.5 Data and Data Quality
3.5.1
data quality
characteristics of data that relate to their ability to satisfy stated requirements
[SOURCE: ISO 14040:2006]
3.5.2
double counting
two or more reporting entities take ownership of the same greenhouse gas emissions (3.1.2) or emission
reductions
3.5.3
primary data
quantified value of a process (3.2.13) or an activity obtained from a direct measurement or a calculation
based on direct measurements
Note 1 to entry: Primary data need not necessarily originate from the product system (3.2.3) under study because
primary data might relate to a different but comparable product system (3.2.3) to that being studied.
Note 2 to entry: Primary data can include greenhouse gas emission factors (3.1.3) and/or greenhouse gas activity data
...