IEC TR 62921:2016

IEC TR 62921 ®
Edition 2.0 2016-10
TECHNICAL
REPORT
colour
inside
Quantification methodology for greenhouse gas emissions for computers and
monitors
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IEC TR 62921 ®
Edition 2.0 2016-10
TECHNICAL
REPORT
colour
inside
Quantification methodology for greenhouse gas emissions for computers and

monitors
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 13.020.20; 35.160 ISBN 978-2-8322-3647-5

– 2 – IEC TR 62921:2016 © IEC 2016
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Terms and definitions . 8
3 Symbols and abbreviations . 11
4 Principles . 12
4.1 Comparing streamlined CFP to comprehensive CFP . 12
4.1.1 General . 12
4.1.2 Level of streamlining . 13
4.2 Viability of streamlined CFP . 13
4.2.1 Streamlining in IEC TR 62725 . 13
4.2.2 Metrics for streamlining . 14
4.2.3 Principles of CFP from IEC TR 62725 . 16
4.2.4 Uncertainty . 16
5 Approaches to streamlined CFP . 18
5.1 General . 18
5.2 Streamlining of data collection . 18
5.2.1 General . 18
5.2.2 Approaches to streamlining data collection . 18
5.3 Streamlining of data inputs . 19
5.3.1 General . 19
5.3.2 Approaches to streamlining data inputs (processing) . 19
6 Comparative study on existing CFP methodologies . 19
6.1 Examples of current worldwide streamlined CFP methodologies . 19
6.1.1 General . 19
6.1.2 Product attribute to impact algorithm (PAIA) . 20
6.1.3 iNEMI eco-impact evaluator . 20
6.1.4 Orange Telecom environmental methodology . 20
6.1.5 Japan CFP method . 20
6.1.6 China CFP method . 20
7 CFP product category rules . 20
7.1 General . 20
7.2 Goal . 21
7.3 Covered products . 21
7.3.1 In scope . 21
7.3.2 Out of scope . 21
7.4 Use of primary, primary aggregated and secondary data . 22
7.4.1 General . 22
7.4.2 Allocation methods . 22
7.5 Relevant emission factors and databases . 22
7.6 Functional unit . 22
7.6.1 General . 22
7.6.2 Life cycle stages included . 22
7.6.3 Life cycle stages excluded. 22
7.7 Production . 22

7.7.1 General . 22
7.7.2 State-of-the-art calculation recommendations . 23
7.8 Chassis . 23
7.8.1 State-of-the-art calculation recommendations . 23
7.8.2 Additional considerations for input data . 23
7.9 Populated printed wiring board (PWB) (excluding integrated circuits) . 24
7.9.1 State-of-the-art calculation recommendations . 24
7.9.2 Additional considerations for input data . 24
7.10 Integrated circuits (ICs) . 25
7.10.1 State-of-the-art calculation recommendations . 25
7.10.2 Additional considerations for input data . 25
7.11 Display . 26
7.11.1 State-of-the-art calculation recommendations . 26
7.11.2 Additional considerations for input data . 26
7.12 Data storage device . 26
7.12.1 State-of-the-art calculation recommendations . 26
7.12.2 Additional considerations for input data . 27
7.13 Optical disk drive (ODD) . 27
7.13.1 State-of-the-art calculation recommendations . 27
7.13.2 Additional considerations for input data . 27
7.14 Power supply unit (PSU, internal or external) . 27
7.14.1 State-of-the-art calculation recommendations . 27
7.14.2 Additional considerations for input data . 28
7.15 Battery . 28
7.15.1 State-of-the-art calculation recommendations . 28
7.15.2 Additional considerations for input data . 28
7.16 Final assembly . 29
7.16.1 State-of-the-art calculation recommendations . 29
7.16.2 Additional considerations for input data . 29
7.17 Final product packaging . 29
7.17.1 State-of-the-art calculation recommendations . 29
7.17.2 Additional considerations for input data . 29
7.18 Distribution . 30
7.18.1 State-of-the-art calculation recommendations . 30
7.18.2 Additional considerations for input data . 30
7.19 Use . 30
7.19.1 State-of-the-art calculation recommendations . 30
7.19.2 Additional considerations for input data . 31
7.20 End of life (EoL) . 31
7.20.1 State-of-the-art calculation recommendations . 31
7.20.2 Additional considerations for input data . 31
8 Documentation . 31
8.1 General . 31
8.2 CFP database . 32
9 Communication and verification . 32
Annex A (informative) Results of a comparative study on existing relevant streamlined
product carbon footprinting methodologies . 33
Annex B (informative) Generic example of streamlined CFP process for ICT products . 46
B.1 Initial analysis . 46

– 4 – IEC TR 62921:2016 © IEC 2016
B.2 Example calculation for a notebook computer . 46
B.3 Data collection . 47
Annex C (informative) Examples of relevant databases for the IT industry . 48
C.1 Ecoinvent . 48
C.2 US Life Cycle Inventory . 48
C.3 GaBi . 48
C.4 ELCD (European Reference Life Cycle Data System) . 48
C.5 PAIA (Product Attribute to Impact Algorithm) Data . 48
Annex D (informative) Recommended sources for product energy consumption . 49
Bibliography . 50

Figure 1 – Depiction of how streamlined CFP fits into comprehensive CFP . 13

Table 1 – Depiction of how streamlined CFP fits into comprehensive CFP . 15
Table A.1 – Comparison of "streamlined" product carbon footprinting methodologies . 34

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
QUANTIFICATION METHODOLOGY FOR GREENHOUSE GAS
EMISSIONS FOR COMPUTERS AND MONITORS

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
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The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC TR 62921, which is a Technical Report, has been prepared by technical area 13:
Environment for AV and multimedia equipment, of IEC technical committee 100: Audio, video
and multimedia systems and equipment.
This second edition cancels and replaces the first edition published in 2015.
The text of this Technical Report is based on the following documents:
Enquiry draft Report on voting
100/2598/DTR 100/2717/RVC
– 6 – IEC TR 62921:2016 © IEC 2016

Full information on the voting for the approval of this technical report 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 website 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.
INTRODUCTION
Many organizations are looking to adopt product greenhouse gas emissions reporting
mechanisms, including:
• computer and monitor manufacturers, as well as their suppliers and downstream users;
• governmental agencies including France, China, Japan, Korea and the European
Commission;
• retailers and non-regulatory agencies.
There have been several international and regional efforts to provide guidance for calculating
product greenhouse gas emissions. Some of these efforts include IEC TR 62725,
ITU-T L.1410, ETSI TS 103 199, and Greenhouse Gas Protocol ICT Sector Supplement.
Unfortunately, some lack of specificity within these documents allows for variability that can
create a significant difference in product greenhouse gas emission results, depending on how
a practitioner interprets the information. Throughout the process of developing IEC TR 62725,
there was significant discussion regarding the need for further specificity, transparency and
pragmatism in methodology guidance for products covered under IEC TC 100, including
computers and monitors. There is an urgent need to enable methodologies that offer accurate
and defensible estimates of impact in a rapid and effective manner. This Technical Report
aims to fill in some of those gaps.
This Technical Report builds upon the structure laid out by IEC TR 62725. Its goal is to
support universal streamlined product greenhouse gas methodologies for practitioners, with a
further goal of harmonizing the various regional efforts currently in progress.
This Technical Report’s quantification methodology aims to be compliant with, and therefore
be used within, a number of these broader standards efforts. It will provide detailed guidance
for estimating greenhouse gas emissions for computers and monitors, in order to obtain
consistent, accurate results. The benefit of consistent results is that they can assist multiple
efforts, including but not limited to:
• supporting customer enquiries;
• instituting sustainable design practices;
• initiating conversations around emissions reduction strategies with suppliers and
downstream users;
• targeting data collection within the supply chain in order to address data quality issues.

– 8 – IEC TR 62921:2016 © IEC 2016
QUANTIFICATION METHODOLOGY FOR GREENHOUSE GAS
EMISSIONS FOR COMPUTERS AND MONITORS

1 Scope
This Technical Report outlines detailed guidance to streamline the quantification of
greenhouse gas emissions for computers and monitors. Other audio, video and multimedia
products, such as e-readers, phones, and storage equipment, can be included in future
revisions of this Technical Report.
For this Technical Report, computers and monitors include notebooks, desktops, integrated
desktop computers, tablets, thin clients, workstations and monitors.
This Technical Report provides specific guidance for the use of streamlining techniques that
minimize cost and resources needed to complete greenhouse gas emissions quantifications.
In addition, the product category rules (PCR) section of this Technical Report recommends
“state-of-the-art” process and data assumptions in order to reduce uncertainty. Lastly, this
Technical Report provides an example of how a calculation could be performed.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1
carbon footprint of a product
CFP
sum of greenhouse gas emissions and removals in a product system, expressed as CO
equivalents and based on a life cycle assessment using the single impact category of climate
change
Note 1 to entry: The CO equivalent of a specific amount of a greenhouse gas is calculated as the mass of a
given greenhouse gas multiplied by its global warming potential.
Note 2 to entry: Results of the quantification of the CFP are documented in the CFP study report expressed in
mass of CO e per functional unit.
[SOURCE: ISO/TS 14067:2013, 3.1.1.1, modified – Notes 2 and 3 have been removed and
Note 4 has been renumbered as Note 2.]
2.2
comprehensive carbon footprint of a product
carbon footprint of a product (2.1) that is product-specific and includes the carbon impacts for
every component and process in that product’s life cycle
2.3
computer
device which performs logical operations and processes data
Note 1 to entry: Computers are composed of, at a minimum:
a) a central processing unit (CPU) to perform operations;
b) user input devices such as a keyboard, mouse, digitizer or game controller; and
c) a computer display screen to output information.
[SOURCE: ENERGY STAR® Program Requirements for Computers]

2.4
desktop
computer whose main unit is designed to be located in a permanent location, often on a desk
or on the floor
Note 1 to entry: Desktops are not designed for portability and are designed for use with an external monitor,
keyboard, and mouse. Desktops are intended for a broad range of home and office applications, including point of
sale applications.
[SOURCE: ENERGY STAR® Program Requirements for Computers]
2.5
greenhouse gas emissions
GHG emissions
total mass of greenhouse gases released to the atmosphere over a specified period of time
[SOURCE: ISO 14064-1:2006, 2.5, modified – Use of the plural in the terms.]
2.6
integrated desktop computer
computer in which the computing hardware and monitor are integrated into a single housing,
and which is connected to a.c. mains power through a single cable
Note 1 to entry: Integrated Desktop Computers come in one of two possible forms:
a) a system where the monitor and computer are physically combined into a single unit; or
b) a system packaged as a single system where the monitor is separate but is connected to the main chassis by a
d.c. power cord and both the computer and monitor are powered from a single power supply.
As a subset of desktops, integrated desktop computers are typically designed to provide similar functionality as
desktops.
[SOURCE: ENERGY STAR® Program Requirements for Computers]
2.7
monitor
product with a display screen and associated electronics, often encased in a single housing,
that as its primary function produces visual information from a computer, workstation, or
server
Note 1 to entry: Visual information input can be received via one or more inputs (e.g., VGA, DVI, HDMI,
DisplayPort, IEEE 13994, USB), external storage (e.g. USSB flash drive, memory card), or a network connection.
[SOURCE: ENERGY STAR® Program Requirements for Displays]
2.8
notebook computer
computer designed specifically for portability and to be operated for extended periods of time
both with and without a direct connection to AC mains power source
Note 1 to entry: Notebooks include an integrated monitor, a non-detachable, mechanical keyboard (using physical,
moveable keys) and pointing devices.
[SOURCE: ENERGY STAR® Program Requirements for Computers]
2.9
primary data
data collected from specific processes in the studied product’s life cycle
[SOURCE: GHG Protocol Product standard:2011]

– 10 – IEC TR 62921:2016 © IEC 2016
2.10
primary aggregated data
data that are collected directly from suppliers or industry associations on a product type (not
specific product) and aggregated
Note 1 to entry: This is an approach in which single components can be sourced from multiple suppliers each with
multiple facilities and multiple downstream suppliers. Primary data for every item is impossible.
2.11
product category rules
PCR
set of specific rules, requirements and guidelines for quantification and communication on the
carbon footprint of a product for a specific product category
[SOURCE: ISO TS 14067:2013, 3.1.4.12, modified — “for developing Type III environmental
declarations for one or more product categories” has been replaced by "for quantification and
communication on the carbon footprint of a product for a specific product category".]
2.12
secondary data
process data that are not from specific processes in the studied product’s life cycle
[SOURCE: GHG Protocol Product standard:2011]
2.13
state-of-the-art
developed stage of technical capability at a given time as regards
products, processes and services, based on the relevant consolidated findings of science,
technology and experience
[SOURCE: ISO/IEC Guide 2:2004, 1.4, modified — The domain “” has
been added before the definition.]
2.14
streamlined carbon footprint of a product
carbon footprint of a product (2.1) that involves some level of simplification compared to a
comprehensive carbon footprint
Note 1 to entry: Typical approaches to streamlining a product carbon footprint calculation consist of simplifying
data collection and/or reducing the number of data inputs required.
2.15
slate
tablet
computer designed for portability that meets all of the following criteria:
a) includes an integrated display with a diagonal size greater than 1 650 mm (6,5 inches)
and less than 4 420 mm (17,4 inches);
b) lacking an integrated, physical attached keyboard in its as-shipped configuration;
c) includes and primarily relies on touchscreen input (with optional keyboard);
d) includes and primarily relies on a wireless network connection (e.g., Wi-Fi, 3G, etc.); and
e) is primarily powered by an internal battery (with connection to the mains for battery
charging, not primary powering of the device)
[SOURCE: ENERGY STAR® Program Requirements for Computers]

2.16
thin client
independently-powered computer that relies on a connection to remote computing resources
(e.g., computer server, remote workstation) to obtain primary functionality
Note 1 to entry: Main computing functions (e.g. program execution, data storage, interaction with other Internet
resources) are provided by the remote computing resources.
Note 2 to entry: Thin clients covered by this Technical Report are
a) limited to devices with no rotational storage media integral to the computer and
b) designed for use in a permanent location (e.g. on a desk) and not for portability.
[SOURCE: ENERGY STAR® Program Requirements for Computers]
2.17
uncertainty analysis
systematic procedure to quantify the uncertainty introduced in the results of a life cycle
inventory analysis due to the cumulative effects of model imprecision, input uncertainty and
data variability
Note 1 to entry: Uncertainty information typically specifies quantitative estimates of the likely dispersion of values
and a qualitative description of the likely causes of the dispersion.
[SOURCE: ISO 14040:2006, 3.33, modified – The note has been changed.]
2.18
workstation
high-performance, single-user computer typically used for graphics, CAD, software
development, financial and scientific applications among other compute intensive tasks
[SOURCE: ENERGY STAR® Program Requirements for Computers]
3 Symbols and abbreviations
AC alternating current
CAD computer-aided design
CFP carbon footprint of a product
CPU central processing unit
DQI data quality inventory
DR distinction rate
DVI digital visual interface
EE product electrical and electronic product
EoL end-of-life
FS false signal rate
HDD hard disk drive
HDMI high-definition multimedia interface
ICs integrated circuits
ICT information and communications technology
IEEE institute of electrical and electronics engineers
kg CO e kilograms of carbon dioxide equivalent
LCA like cycle assessment
LCD liquid crystal display
– 12 – IEC TR 62921:2016 © IEC 2016
LCI life cycle inventory
LCIA life cycle impact assessment
LCT life cycle thinking
ODD optical disk drive
PAIA product attribute to impact algorithm
PCR product category rules
PSU power supply unit
PWB printed wiring board
SSD solid state drive
TEC typical energy consumption
USB universal serial bus
VGA video graphics array
VT validation team
4 Principles
4.1 Comparing streamlined CFP to comprehensive CFP
4.1.1 General
The carbon footprint of a product estimates the total potential contribution of a product to
global warming by quantifying all significant greenhouse gas emissions and removals over the
product's life cycle. Comprehensive CFPs are product-specific and include the carbon impacts
for every component and process in that product’s life cycle. A comprehensive CFP takes a
significant amount of resources, time, and data-demands to complete.
Given these challenges, streamlined CFP approaches are critical, particularly in industries
such as the information and communications technology (ICT) industry, which have complex
products and rapid product-development cycles. The streamlined approach reduces the
amount of time and resources needed for data gathering and calculation in order to achieve
the needed level of accuracy. Therefore, the streamlining approach follows the rule that only
the materials, components and processes that are associated with the most significant
product carbon impacts are included in the analysis.
While many different definitions of a streamlined CFP exist, the common characteristic is that
they all involve some level of simplification, as compared to a comprehensive CFP. With
comprehensive CFPs rarely being executed, it is this collection of streamlined CFP
approaches that represent a common approach to CFP. These streamlined approaches, when
executed according to recognized practices, reduce the burden of a CFP, while still allowing
the necessary goals of the CFP to be achieved (see Figure 1).

Full CFP
Streamlined CFP
100 %
Data inputs
1 %
IEC
Figure 1 – Depiction of how streamlined CFP fits into comprehensive CFP
4.1.2 Level of streamlining
While streamlined CFPs are clearly less resource-intensive, the extent of streamlining that is
possible is entirely dependent on the goal of the CFP and, more specifically, the questions
that the CFP is attempting to answer. Typically, the more general the questions are that need
to be answered, the more streamlined the CFP can be.
For example, high-level product CFPs, focused on understanding the overall impact of a
product or which life cycle phases dominate product impact, can be completed using a
streamlined CFP. For such cases, the additional resolution and specificity provided through a
more comprehensive CFP are not needed.
However, if information is needed to assess specific materials or design choices around a
product (i.e. evaluating materials used in packaging, or evaluating trade-offs in product
design), then a more specific and detailed analysis is warranted. In this case, improved data
collection and more primary data input can be required, leading to a more comprehensive
CFP. In general, the more specificity that is required in the CFP results, the more
comprehensive the CFP will need to be.
4.2 Viability of streamlined CFP
4.2.1 Streamlining in IEC TR 62725
Streamlined methodologies that apply a trial estimation approach are described in
IEC TR 62725:2013, 6.4, 6.5, Annex B and Annex D. Rather than applying a quantitative cut-
off threshold (e.g. less than 5 % of the total estimated emissions can be excluded from the
CFP analysis) as described in IEC TR 62725, in the streamlined approach a high level
statistical analysis using available data and Monte Carlo simulations is performed to
determine the life cycle activities that are the biggest contributors to impact and uncertainty.
Targeted data collection is then performed, based on this analysis, to confirm impacts and
further reduce uncertainty to desired levels. Use of a streamlined approach informs the
appropriate cut-off criteria in view of the workability and availability of the process data.
Data collection
– 14 – IEC TR 62921:2016 © IEC 2016
4.2.2 Metrics for streamlining
In order to determine whether the result of a CFP analysis is sufficient given the degree of
uncertainty present in all aspects of the calculation (see 4.2.4), measures of resolution are
often calculated. This can be done as part of a sensitivity check in order to determine the
ability of the CFP analysis to find significant differences between different studied alternatives,
as described in ISO 14044.
One common way to assess whether a result is “good enough” to answer the question posed
is to determine how much overlap there is between the sampled distribution corresponding to
the product of interest and a variety of related alternatives. (For example, this could be a
comparison of the product of interest with another product utilizing a different set of materials
or architecture.) When the uncertain CFP of the product of interest overlaps considerably with
the uncertain CFP of the alternative, then it would be inappropriate to declare that the two
have different CFPs. If there is little overlap, then one could confidently identify a difference
and therefore which of the two alternatives had the lower CFP.
There are several terms used to describe this degree of overlap (i.e. between the estimated
CFP of the product of interest and the estimated CFP of an alternative) including the
comparison indicator, distinction rate (DR), or false signal rate (defined below). For this
discussion, distinction rate will be used to signify how distinct the product of interest is from a
selected baseline. Distinction rate essentially quantifies the frequency at which one of the
alternatives has a distinctly lower CFP than the other alternative or a prescribed benchmark
(described subsequently).
To calculate the distinction rate between the product of interest (B) and the baseline or
benchmark (A), the expected distribution for CFP as well as for CFP should be sampled via
B A
statistical simulation, such as through Monte Carlo sampling. The formulation for this
distinction rate (DR) is then expressed as:
DR = P (CFP < CFP )
B A
where
DR is the distinction rate;
P is the probability;
CFP is the CFP for the product of interest;
B
CFP is the CFP for some baseline comparison product.
A
The probability of CFP < CFP , can be estimated directly from the Monte Carlo simulation
B A
results by comparing scenario pairs CFP and CFP and calculating the relative frequency
A B
where CFP < CFP . The false signal rate (FS) is a specific version of the distinction rate
B A
defined as the frequency of observing a result where the CFPs of the products are
comparatively different (higher than, or lower than the other) than would be expected based
on the relative position of the mean CFP (µ, µ for product A and µ for product B). That is:
A B
P(CFP < CFP ), where µ <µ

B A A B
FS=

P(CFP < CFP ), where µ >µ
 A B A B
It is important to note that there is often correlation among life cycle activities across a
product of interest and a baseline, particularly for downstream activities such as the grid
mixes associated with use phase.
In assessing the difference between the uncertain impact of a product of interest and a
baseline, therefore, consider correlation (i.e. the degree to which two or more variables are
related in some fashion) to avoid statistical bias. To that end, the analysis should probably be
conducted simultaneously for both the product and baseline such that for each Monte Carlo
run the same sample sets are used for the correlated activities and parameters.

Another form of resolution metric which is often reported is referred to as the comparison
indicator (β), which is defined as the probability that the ratio between the product of interest
and the baseline is less than one, that is
 
CFP
B
β= P < 1
 
CFP
 A 
where
β is the comparison indicator;
P is the probability;
CFP is the CFP for the product of interest;
B
CFP is the CFP for some baseline comparison product.

A
This enables characterization of the likelihood that the baseline has lower impact than the
product of interest.
A decision regarding the sufficiency of the analysis can then be made when β is greater than
a prescribed threshold. This threshold is a decision parameter that controls the level of risk
that a decision-maker is willing to take and should be set by the decision-maker for a given
context. If the metric of interest does not indicate that there is high statistical confidence in
the comparison result (i.e. there is high risk that a conclusion drawn on this result will be
directionally incorrect), the analyst has the option either to declare the products not
differentiable or to attempt to collect additional more precise data to improve the resolution of
the analysis.
An example of a hypothetical benchmark could be the use of the same data distribution for a
product of interest displaced by a difference threshold established in the goals of the study.
This difference threshold distance could be defined as a percentage of the magnitude of the
mean, i.e. shifting the mean of A (µA) by 10 %. The reason for this sort of a benchmark would
be if data for another product were not available. Another example could be a product
analysis for a larger or smaller screen size in the case of a laptop.
An example of the above calculations for a hypothetical comparison is shown in Table 1.
Table 1 – Depiction of how streamlined CFP fits into comprehensive CFP
Footprint of Footprint of
Monte Carlo Is Is Ratio
product of alternative
trial CFP < CFP ? CFP < CFP ? CFP /CFP
B A A B B A
interest (CFP ) product (CFP )
B A
1 73 71 – Y 1,02
2 77 131 Y – 0,59
3 90 92 Y – 0,99
4 92 122 Y – 0,76
5 98 74 – Y 1,32
6 103 122 Y – 0,85
7 81 90 Y – 0,90
8 96 105 Y – 0,91
9 104 87 – Y 1,19
10 100 154 Y – 0,65
91 105 0,7 0,3 0,70
Average CFP Average CFP Comparison
Distinction rate False signal rate
B A
(µ ) (µ ) (DR) (FS) indicator (β)
B A
– 16 – IEC TR 62921:2016 © IEC 2016
4.2.3 Principles of CFP from IEC TR 62725
4.2.3.1 Life cycle thinking (LCT)
In the development of methodology to quantify the greenhouse gas emissions throughout an
electrical and electronic (EE) product’s life cycle, take all stages of the life cycle of a product
into consideration.
4.2.3.2 Relevance
Select and use data, methods, criteria and assumptions that are appropriate to the
assessment of greenhouse gas emissions and removals from the goal and scope definition
being studied.
4.2.3.3 Completeness
Include all greenhouse gas emissions and removals that provide a significant contribution to
the assessment of greenhouse gas emissions and removals arising from the goal and scope
definition being studied.
4.2.3.4 Consistency
Apply assumptions, methods and data in the same way throughout the greenhouse gas
emissions for an EE product’s life cycle to arrive at conclusions in accordance with the goal
and scope definition.
4.2.3.5 Accuracy
Reduce bias and uncertainties as far as is appropriate to the goal o
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