IEC 62125:2019

IEC 62125 ®
Edition 1.0 2019-09
INTERNATIONAL
STANDARD
colour
inside
Environmental considerations specific to insulated electrical power and control
cables
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IEC 62125 ®
Edition 1.0 2019-09
INTERNATIONAL
STANDARD
colour
inside
Environmental considerations specific to insulated electrical power and control

cables
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.060.20 ISBN 978-2-8322-7374-6

– 2 – IEC 62125:2019 © IEC 2019
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions and symbols. 7
3.1 Terms and definitions . 7
3.2 Symbols . 9
4 General principles . 11
5 Environmental checklist approach. 11
5.1 What is the checklist approach? . 11
5.2 Checklist . 12
6 Life cycle assessment (LCA) of cables . 12
6.1 General . 12
6.2 Goal and scope . 13
6.2.1 LCA study goal . 13
6.2.2 Functional unit . 13
6.2.3 Reference flow . 14
6.2.4 System boundary . 14
6.2.5 Cut-off criteria . 15
6.2.6 Assumptions and limitations . 15
6.3 Life cycle inventory (LCI) . 15
6.3.1 General . 15
6.3.2 Data collection . 15
6.3.3 Data selection. 16
6.3.4 Allocation procedure . 16
6.4 Life cycle impact assessment (LCIA) . 16
6.5 Interpretation . 17
6.6 Single environmental indicator approach . 17
7 Environmental and energy cost-based conductor size optimization – ECSO . 18
7.1 Overview. 18
7.2 Basic rules . 18
7.3 Factors . 20
7.4 CO evaluation . 20
7.4.1 General . 20
7.4.2 CO emissions during manufacturing, transportation, installation and
final disposal . 20
7.4.3 CO emissions at the use phase . 20
7.5 Calculation method . 20
7.5.1 General . 20
7.5.2 Calculation of initial cost . 20
7.5.3 Calculation of running costs . 21
7.5.4 Conductor resistance . 21
7.5.5 Optimum current . 21
7.5.6 Optimum conductor size . 22
7.5.7 Energy reduction related to the use phase of the cable . 22
7.6 Example. 23

8 Environment-related communication . 24
8.1 General . 24
8.2 General principles . 24
8.3 Composition and compliancy to legislation on substances . 25
8.4 Life cycle assessment . 25
8.5 End of life . 25
Annex A (informative) Checklist for the checklist approach . 26
A.1 Preliminary considerations . 26
A.2 Design considerations . 26
A.3 Production considerations . 26
A.4 Considerations for use and end of life phase . 27
Annex B (informative) Example for ECSO . 28
B.1 General . 28
B.2 Cable data . 28
B.3 Calculation condition . 28
B.4 Initial cost . 29
B.4.1 Initial investment . 29
B.4.2 Conversion of CO emissions during material/cable production, removal,
transportation and disposal to cost . 29
B.4.3 Initial cost (sum) . 29
B.4.4 Conductor resistance . 30
B.5 Calculation of running costs . 30
B.5.1 Costs for Joule losses during anticipated life time . 30
B.5.2 Costs for CO emission during anticipated life time . 30
B.6 Life cycle cost . 31
B.7 Optimum current . 31
B.8 Efficiency . 32
B.8.1 Calculation of energy efficiency . 32
B.9 Life cycle cost versus service life . 33
Annex C (informative) Example of environmental communication . 34
Bibliography . 35

Figure 1 – Life cycle phases . 13
Figure 2 – Life cycle costs for conductor size for a certain current . 19
Figure 3 – Optimum current range for minimizing life cycle cost . 19

Table B.1 – Life cycle cost versus service life . 33
Table B.2 – Life cycle cost versus service life, relative to 3C 70 mm . 33

– 4 – IEC 62125:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ENVIRONMENTAL CONSIDERATIONS SPECIFIC TO
INSULATED ELECTRICAL POWER AND CONTROL CABLES

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC
Publication(s)"). Their preparation is entrusted to technical committees; any IEC National Committee interested
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agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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6) All users should ensure that they have the latest edition of this publication.
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Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62125 has been prepared by IEC technical committee 20: Electric
cables.
This first edition cancels and replaces IEC TR 62125, published in 2007. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to
IEC TR 62125:2007:
a) development of the document from TR to international standard;
b) inclusion of a methodology for LCA;
c) inclusion of a methodology for conductor size optimization.

The text of this standard is based on the following documents:
FDIS Report on voting
20/1876/FDIS 20/1881/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 6 – IEC 62125:2019 © IEC 2019
INTRODUCTION
The cable sector has, for many years, considered the impact of electric cables on the
environment with respect to their operating conditions. Transmission system operators,
distribution system operators, manufacturers, installers/contractors, users and authorities
have considerably increased their requirements to take into account the environmental impact
of electric cables.
IEC TC 20 regularly reviews its approach to the incorporation of environmental aspects into
standards for electric cables and their components. Environmental considerations should be
included in both design and redesign work with respect to the raw materials used, energy
consumption, emissions and generation of waste during production, end of life recycling or
disposal, and in-service performance.
This document supersedes IEC TR 62125 published 2007, which intended to give assistance
to writers of standards within IEC Technical Committee 20, to take into account the relevant
environmental aspects that are specific to electric cables in normal use.
This document is addressed to writers of standards, manufacturers and users of power cables
to provide guidance when evaluating:
– the qualitative environmental impact (checklist approach), or
– the quantitative environmental impact (LCA approach), and
– the environmental and energy cost-based conductor size optimization (ECSO).

ENVIRONMENTAL CONSIDERATIONS SPECIFIC TO
INSULATED ELECTRICAL POWER AND CONTROL CABLES

1 Scope
This document provides methodologies addressing environmental evaluation and
communication related to cables in normal use.
It includes an environmental checklist for power cables, the method for life cycle assessment
(LCA) and a methodology for conductor size optimization.
The results obtained by applying such methodologies can be used for external communication.
Environmental communication can also include other topics, such as material declaration.
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.
IEC 60287-3-2:2012, Electric cables – Calculation of the current rating – Part 3-2: Sections on
operating conditions – Economic optimization of power cable size
ISO 14040:2006, Environmental management – Life cycle assessment – Principles and
framework
ISO 14044:2006, Environmental management – Life cycle assessment – Requirements and
guidelines
3 Terms, definitions and symbols
3.1 Terms and definitions
3.1.1
life cycle assessment
LCA
compilation and evaluation of the inputs, outputs and the potential environmental impacts of a
product system throughout its life cycle
[SOURCE: ISO 14040:2006, 3.2]
3.1.2
life cycle inventory
LCI
phase of life cycle assessment involving the compilation and quantification of inputs and
outputs for a product throughout its life cycle
[SOURCE: ISO 14040:2006, 3.3]
– 8 – IEC 62125:2019 © IEC 2019
3.1.3
life cycle impact assessment
LCIA
phase of life cycle assessment aimed at understanding and evaluating the magnitude and
significance of the potential environmental impacts for a product system throughout the life
cycle of the product
[SOURCE: ISO 14040:2006, 3.4]
3.1.4
life cycle thinking
LCT
consideration of all relevant environmental aspects during the entire lifecycle of products
[SOURCE: IEC 62430:2009, 3.11]
3.1.5
reference flow
measure of the outputs from processes in a given product system required to fulfil the function
expressed by the functional unit
[SOURCE: ISO 14040:2006, 3.29]
3.1.6
functional unit
quantified performance of a product system for use as a reference unit
[SOURCE: ISO 14040:2006, 3.20]
3.1.7
environment
surroundings in which a product or system exists, including air, water, land, natural resources,
flora, fauna, humans and their interrelation
Note 1 to entry: "Environment" in this document means ecological environment. It does not refer to surrounding
factors influencing the cable (such as humidity or temperature), nor to the business environment.
[SOURCE: IEC Guide 109:2012, 3.3, modified – Note 1 to entry has been added.]
3.1.8
life cycle
consecutive and interlinked stages of a product system, from raw material acquisition or
generation from natural resources to final disposal
[SOURCE: ISO 14040:2006, 3.1]
3.1.9
environmental impact of a product
change to the environment, whether adverse or beneficial, wholly or partially resulting from
the life cycle of a product
3.1.10
unit process
smallest element considered in the life cycle inventory analysis for which input and output
data are quantified
[SOURCE: ISO 14040:2006, 3.34]

3.2 Symbols
temperature coefficient of conductor resistance at
α 1/K
20 °C (for copper: 0,003 93, for aluminium: 0,004 03)
θ maximum rated conductor operating temperature °C
θ ambient average temperature °C
a
θ mean operating conductor temperature °C
m
temperature rise of conductor Δθ = (θ − 20 °C)
Δθ °C
m
µ loss load factor, see IEC 60853-1 –
cu/km
cost for ancillary materials and installation materials
C
af
(like conduits)
cu/km
cable cost including transportation
C
C
initial cost of the cable being considered cu/km
C
I
cu/km
cost for CO emission during mining, manufacturing,
C
I(CO )
transportation, installation and final disposal for a
certain conductor size
C initial cost of the next smaller standard size of cu/km
I1
conductor
cost for CO emission during mining, manufacturing, cu/km
C
I1(CO )
transportation, installation and final disposal for the
next smaller size of conductor
C initial cost of the next larger standard size of cu/km
I2
conductor
cost for CO emission during mining, manufacturing, cu/km

C 2
I2(CO )
disposal for the
transportation, installation and final
next larger size of conductor
C present value of the cost of joule losses during N cu/km
J
years
present value of the costs for CO emission during cu/km
C
J(CO )
anticipated life time due to Joule losses
cable installation (including laying, removal and cu/km
C
L
disposal) cost
life cycle cost cu/km
C
T
life cycle cost for the next smaller size of conductor cu/km
C
T1
life cycle costs for the next larger size of conductor cu/km
C
T2
arbitrary currency unit
cu
CO emission of the cable of conventional size per CO -kg/year
E
2 2
CONV
year during use phase
– 10 – IEC 62125:2019 © IEC 2019
CO emission of the cable of optimum size per year CO -kg/year
E
2 2
OPTI
during use phase
F auxiliary quantity defined by Formula (8) cu/W
load factor
f
power factor (= cos φ, φ being the phase angle
f
between voltage and current)
maximum load current A
I
max
upper limit of I A
I
max
upper
lower limit of I A
I
max
lower
CO emissions during mining, manufacturing, CO -kg/km
I
2 2
Z
transportation, installation and final disposal
CO emission for generation of unit power to be CO -kg/kWh
K
2 2
adjusted to the national situation
k Coefficient based on wiring system, e.g. 3 phase-3
w
wire kw = √3, for DC cables kw = 1
cable length km
L
coefficient for converting CO emissions to cost CO -cu/kg
M
2 2
to be adjusted to the national situation
service life, a synonym (anticipated life time) year
N
N number of loaded phase conductors –
p
P cost of one kilowatt-hour at relevant voltage level cu/kWh
R conductor resistance of conductor per length
Ω/km
(considered to be a constant value at an average
operating temperature)
R conductor resistance per length of the next smaller
Ω/km
standard conductor size
R conductor resistance per length of the next larger
Ω/km
standard conductor size
conductor resistance at 20 °C per length, (ohm/km)
Ω/km
R
AC resistance per length of the cable with
Ω/km
R
conv
conventional size for AC system and DC resistance
per length of the cable with conventional size for DC
system
AC resistance per length of the cable with optimum
Ω/km
R
opti
size for AC system and DC resistance per length of
the cable with optimum size for DC system
S cross-sectional area of a cable conductor
mm
S cross-sectional area of the next smaller standard
mm
conductor size
S cross-sectional area of the next larger standard
mm
conductor size
U system voltage V
W amount of power consumption per year kWh/year
distribution losses with the cable of conventional size kWh/year
W
conv
distribution losses of the cable with optimum size kWh/year
W
opti
annual operating days days
Y
4 General principles
The environmental impact of an electric cable shall be considered throughout all life cycle
phases: from design till end of life. This is called the concept of life cycle thinking.
There are various tools for the environmental evaluation of the products, for example:
– a checklist approach, which is a qualitative consideration of the environmental aspects
related to the life cycle steps of the product, i.e. use of the checklist in accordance with
Clause 5 and Annex A, that is based on IEC Guide 109 and specifically focused on power
cables;
– life cycle assessment (LCA), which is a scientific tool providing a quantitative evaluation of
the environmental impact occuring during the whole life cycle of the product, i.e. use of
the life cycle assessment in accordance with Clause 6 for assessment of the
environmental impacts of a product.
The use of LCA methodology is recommended, as it provides quantified and detailed
information on product environmental impact. Nevertheless, considering the knowledge and
resources required to perform LCA studies, the checklist might be acceptable, for instance if
certain aspects are considered without determining the complete environmental impact. This
choice has to be made depending on objectives and knowledge and resources available.
Apart from life cycle thinking, other approaches can be used, such as:
– ECSO, a tool (described in Clause 7) to evaluate and optimize the conductor size by
combining environmental and energy costs. ECSO is the optimization of the conductor
size so that the sum of the total costs and the conversion costs of CO emissions
throughout the life phases (defined in 6.2.4) of the cable is minimized.
Environmental improvement shall be balanced against other factors, such as product function,
performance, health and safety, cost, marketability and quality, legal and regulatory
requirements and other standards.
5 Environmental checklist approach
5.1 What is the checklist approach?
The checklist approach is a simple method without quantification of the complete
environmental impact. It is a working aid to evaluate the cable design and the cable choice for
a certain application so as to find environmentally related aspects that may require
consideration. The lists in 5.2 and Annex A address key factors that have an impact on the
environment.
– 12 – IEC 62125:2019 © IEC 2019
It should be noted that considerations of the points in 5.2 and Annex A do not always lead to
reduction of the adverse environmental impact of the product throughout its lifetime: any
decision to improve one environmental indicator can impact negatively another indicator. A
possible way to confirm and quantify the environmental improvement is the use of the LCA
methodology described in Clause 6.
5.2 Checklist
The following list, which is in accordance with IEC Guide 109:2012, Annex A, addresses key
factors that may have an impact on the environment. Determine whether cable design and
cable choice for the application consider the following aspects:
– material conservation:
• minimal material content in the product;
• minimal material content in the packaging;
• minimal number of different materials;
• maximum separability of different materials;
• maximum recyclability of used materials;
• reusability of product parts and components;
• reusability and upgradability of the product as a whole;
• possibility of using recycled materials;
• possibility of using refurbished product parts and components;
• minimal size of product;
• minimal mass of product.
– energy conservation:
• minimal energy consumption during the product's manufacture and operation;
• power management, e.g. automatic switch to standby mode.
– pollution prevention:
• avoidance of hazardous substances;
• avoidance of substance emissions into the environment (air, water, soil);
• avoidance of other releases, e.g. radiation, noise, dust.
– avoidance of waste:
• modularity allowing multiple use of components (e.g. common chargers for different
applications).
This list is not exhaustive; more items could be added for specific reasons. Not every item on
the list will apply to every situation. Some more specific guidance related to electric cables is
given in Annex A.
6 Life cycle assessment (LCA) of cables
6.1 General
As recommended by IEC Guide 109, the basis of the assessment of product-related
environmental impact is life cycle thinking. The environmental impact of a product needs to be
evaluated by taking into account its whole life cycle, and by evaluating various environmental
indicators. LCA is a tool covering all life cycle stages (cradle to grave).
Figure 1 illustrates the elements in an LCA. An LCA shall be carried out in accordance with
the methodology of life cycle assessment (LCA) specified in ISO 14040 and ISO 14044.

Some basic steps to conduct this life cycle assessment of power cables are described in 6.2
to 6.6.
It has to be noted that an environmental optimum may not coincide with the economical
optimum. LCA has to be seen as an evaluation tool to quantify the environmental impact and
is not related to economic aspects. Regarding economic consideration, other methodologies
can be applied, such as environmental life cycle cost (monetary expression, i.e. monetization
of environmental indicators) or ECSO (see Clause 7), which combine environmental and
economic aspects.
Figure 1 – Life cycle phases
6.2 Goal and scope
6.2.1 LCA study goal
The goal and scope of the LCA study should be clearly defined and be consistent with the
intended application of the LCA.
The following items shall be unambiguously stated:
– the intended application;
– the decision context (reason for carrying out the study);
– the intended audience, i.e. to whom the results of the study are intended to be
communicated.
6.2.2 Functional unit
The functional unit defines the quantification of the identified functions (performance
characteristics) of the product being considered. The purpose of the functional unit is to
provide a reference to which the inputs and outputs are related. This reference is necessary
to ensure comparability of LCA results.

– 14 – IEC 62125:2019 © IEC 2019
The functional unit shall mention:
– the main function delivered to the user;
– the quantified level of performance to be achieved by the main function.
For example, for a standard functional unit of power cables:
– "To transmit energy expressed for x A over a distance of y km during n years at a b % use
rate, in accordance with the relevant standards." or
– "To transmit energy of x kWh over a distance of y km during n years at a b % use rate, in
accordance with the relevant standards."
NOTE Use rate represents the operating time per year and can be expressed as
– the % of annual operating days (in %);
– the number of operating hours per year (in hours);
– the number of operating days per year (in days).
Other functional units can be defined depending on the goal of the LCA and the intended
application.
6.2.3 Reference flow
Each functional unit corresponds to a reference flow. This reference flow describes all the
needed flows to fulfil the functional unit and includes at least a reference power cable.
The reference flow shall include:
– the quantification of the reference product and its mass (kg), used to fulfil the functional
unit;
– the additional materials not found in the reference product that include waste and
discarded materials generated at each life cycle stage (manufacturing process, cutting,
installation, etc.);
– elements, flows and processes required to distribute, install, use (maintenance, repairs,
replacements…) remove, dismantle and treat the reference product.
6.2.4 System boundary
The system boundary describes the unit processes that are included in the LCA. Concerning
power cables, the main impacting life phases are known to be the manufacturing (of the raw
materials) and the use phases of the cables.
The life phases include:
– the manufacturing phase with:
• raw material extraction and processing, transport of raw materials to the cable
manufacturer;
• cable manufacturing;
– the transportation phase with the transportation of the power cable from the
manufacturer to the installation place;
– the installation phase including processes, components and energy accounted for the
installation phase. Owing to the wide range of possible installation of these products, it
may be decided to exclude the installation phase from the life cycle assessment's
perimeter;
– the use phase with the energy consumption related to cables losses and other impacts, if
any. The impact of the use phase will clearly describe the scenario used, such as cable
lifetime, cable load factor, conductor resistivity and current load of the conductor;

– the end of life phase, including cable removal and transportation, as well as end-of-life
treatment (grinding, separation, landfill, recycling, energy recovery, etc.).
The LCA has to be composed by all the life cycle steps. The LCA methodology could be used
in some cases and for some reasons (for example, if it is required by a customer) to analyze
just some phases, for instance "cradle to gate" analysis that only takes into consideration raw
materials and cable manufacturing. This approach does not result in an LCA as such.
6.2.5 Cut-off criteria
Criteria for the exclusion of inputs and outputs shall not be applied to hide data. Any
application of the criteria for the exclusion of inputs and outputs shall be documented. The
cut-off criteria depend on the goal and scope definition and the boundary setting. Various cut-
off criteria may be used to decide inputs and outputs to be included in the assessment, such
as weight, energy and environmental influence. The total of neglected input flows (for
example, raw materials to manufacture the cable) shall be clearly identified. Moreover,
particular care should be taken to include material and energy flows known to have the
potential to cause significant emissions into air, water and soil in relation to the environmental
indicators of this document.
As an example, the following cut-off criteria can be applied:
– the mass of intermediate flows not taken into account shall be less than or equal to 5 % of
the mass of the elements of the reference product corresponding to the functional unit;
– the energy flows not taken into account shall be less than or equal to 5 % of the total use
of primary energy during the life cycle of the reference product corresponding to the
functional unit.
6.2.6 Assumptions and limitations
Every assumption made – if necessary because of, for example, lack of data impossible to
retrieve – should be clearly specified.
6.3 Life cycle inventory (LCI)
6.3.1 General
The life cycle inventory includes the collection of input data about resources, products or
energy entering into the process, as well as output data about product, material or energy
flow that leaves a process.
6.3.2 Data collection
The data to be included in the LCA study shall be obtained for each process included in the
system boundary. For each unit process within the system boundaries, inputs and outputs
related to the reference flow shall be collected including:
– consumption of materials, energy, water;
– emissions to air, water, soil;
– waste from the processes analysed.
The data gathered, whether they are measured, calculated or estimated, shall be used to
quantify the inputs and output flows of a process. If data cannot be collected directly on-site
(primary data), data can be obtained from high-quality and well-recognized databases
(secondary data).
Secondary data shall be identified and consistent with the scope of the study in terms of time-
related, geographic and technologic coverage. The databases used for the LCA shall be
mentioned in the LCA report.
– 16 – IEC 62125:2019 © IEC 2019
NOTE Examples of public database are:
– Ecoinvent database [1] ;
– European Life Cycle Database (ELCD) [2];
– U.S. Life Cycle Inventory Database (USLCI) [3].
6.3.3 Data selection
Specific or average data derived from specific production processes shall be the first choice
as a basis for the LCA study of power cables.
It is recommended that:
– the collected flows should be averaged over a sufficiently long period, preferably over a
year, to even out any seasonal peaks;
– the collected data should be representative of a current scenario in terms of geographic
coverage and technologic coverage. When data are collected from several sites, the data
should be collected from representative sites. The method used to aggregate the multi-site
data (i.e. measurements taken on each site) and the rules applying to the creation of data
sources should be documented in the LCA report.
6.3.4 Allocation procedure
Most industrial processes produce more than the intended product. Normally, more than one
input is needed to produce one product and sometimes products are co-produced with other
products. When dealing with systems involving multiple products, allocation rules need to be
set up to share the inputs and outputs to each product. Several methods are described in
ISO 14044.
To allocate the consumptions of energy, materials, and water and emissions in air, water, soil
and waste, it is necessary to apply a physical allocation rule being representative for the
parameter, which shall be allocated to the functional unit.
The physical parameter of assignment of input and output flows may be for example mass,
surface, or the number of units produced according to what is suitable for the system of
production. Allocation should be considered carefully and should be justified.
6.4 Life cycle impact assessment (LCIA)
It includes the assignment of the LCI results to the selected impact categories and the
potential environmental impacts in each category.
The impact assessment methodology used to carry out the LCA should be clearly described.
The impact assessment is carried out preferentially following the ILCD (International
Reference Life Cycle Data System) recommendations given in the ILCD handbook [4].
Regarding the global warming potential, this can be expressed in two possible ways:
a) by quantifying its impact with the "CO equivalent" units, intended as the "mid-point
category" as potential direct impact to the environment;
b) by quantifying its impact up to the final damage to the "endpoint categories", for example:
damage to human health, environment, resource depletion.
The same two approaches can be followed for any other impact category used to evaluate the
LCA impact of the cable.
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Numbers in square brackets refer to the Bibliography.

6.5 Interpretation
The LCA interpretation shall include:
a) an interpretation starting with the identification of significant issues;
b) a description of the completeness (taking into account system boundaries and cut-off
criteria);
c) sensitivity and consistency checks.
The result should be interpreted taking into account the initial aim of the study.
If the aim of the study is the comparison between alternative cables, the results interpretation
should be focused on the differences of the cables, not on their common properties.
Whilst if the aim of the study is the identification of the main impact elements of a cable in
order to improve its environmental design (for example: what is the most impacting raw
material? what is the most impact life cycle step – production, use or other? Etc.), the
conclusions should be structured consequently.
This means that a strong result interpretation implies focusing on the elements relevant for
the product to be analyzed and for the objectives of the LCA.
For this reason, the interpretation is also feedback about the quality of the LCA performed,
since it can make evident the need to review the study before releasing the definitive results,
allowing for possible significant elements to be included in the LCA that could have been
neglected at first.
The interpretation should also be carried out with the purpose of identifying the main
conclusions to communicate in the LCA report.
As a matter of fact, the LCA results (after the "impact assessment" step) are represented by
one or more numbers and charts, indicating how much the cable life cycle impacts on the
environment. Those numbers are often not very clear to non-expert readers. Therefore, they
should be translated into final conclusions by putting them through the "interpretation" step.
Such conclusions – in order to be communicated to the public – should be defined
consistently with the basic aim of the study.
6.6 Single environmental indicator approach
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