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LCA part3

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applications and users. For the particular case of paint they give the
following example: ‘The results of the LCA will be used by the ecolabeling board to identify areas where
criteria should be set in order to promote the most environmentally friendly products within this product
Several authors note, furthermore, that it may be necessary to revise the initial objectives and intended
decisions during the course of an LCA (e.g. ISO 14041, 1998E; Lindfors et al., 1995a; Wenzel et al.,
1997). Performing an LCA is an iterative rather than purely sequential process.
Finally, various references distinguish between different categories of application (e.g. Heijungs et al.,
1992; Weidema, 1993; Fleischer et al., 1995; Guinée, 1995; Lindfors et al., 1995a; Braunschweig et al.,
1996; UNEP, 1996; ISO 14040, 1997E; Cowell et al., 1997; UNEP, 1999; Wenzel, 1998). The
differences between these various categorisation schemes are mainly a matter of taste and not
examined as such here. The key question is, rather, whether it is possible to distinguish groups of
applications differing in their impact on methodological choices or procedural arrangements in the course
of an LCA study. Some authors offer valuable suggestions for a classification of applications as they
affect methodological choices (Frischknecht, 1997; Frischknecht, 1998; Clift et al., 1998; Weidema,
1998a; Wenzel, 1998). This subject will be discussed in more detail in Section 2.3 (‘Mode of analysis’).
This Guide distinguishes six types of decision situation in which LCA results may be applied (De Bruijn
& Van Duin, 1998; Van Duin & De Bruijn, 1998):
- global exploration of options;
- company-internal innovation;
- sector-driven innovation;
- strategic planning;
- comparison;
- comparative assertion disclosed to the public.
In the case of comparison of product alternatives, it must be determined at some stage what differences
in results are to be deemed significant for concluding that one alternative is environmentally sounder
than another. For procedural reasons it seems wise to address this issue as part of the goal definition,
at the very outset of the study.
Part 3: Scientific background 65 May 2001
Clause 8 of ISO 14041 (1998E) specifies that the study report on the Goal and Scope definition should
meet the following requirements (see textbox):
For Goal and Scope definition, Lindfors et al. (1995a) list the following reporting issues:
- The members of the reference panel or review group shall be reported, if relevant.
- A short resumé of the discussions in the reference panel shall be given, with focus on conflicting
or: a report from the reviewer(s) on the critical review, concerned party review, or validation,
or: a statement that an external validation or review process has not been carried out, including a
justification of that decision (e.g. since concerned parties have been involved in the conduct of the
- The commissioner of the study shall be stated.
- A presentation of the practitioners, including their background, shall be given (an LCA-oriented
- The purpose shall be clearly and unambiguously stated, in terms of the reasons for carrying out the
- A clear statement on the decisions intended to be based on the findings should be made.
- A statement on the intended users or audience should be made.
- The main user function(s) (e.g. protection and/or colouring for paints) forming the basis for the LCA
shall be clearly defined and reported.
- Any deviation from initial plans may be reported.
- Any other limitations or introduced assumptions relevant to the results of the study shall be
The results of an LCI study shall be fairly, completely and accurately reported to the intended audience as
described by the relevant parts of clause 6 of ISO 14040:1997E. If a third-party report is required, it shall
cover all items marked with an asterisk. All additional items should be considered.
a) Goal of the study
1) reasons for carrying out the study *;
2) its intended applications *;
3) the target audiences *.
b) Scope of the study:
1) modifications together with their justification;
2) function:
i) Statement of performance characteristics *;
ii) Any omission of additional functions in comparisons *;
3) functional unit:
i) Consistency with goal and scope *;
ii) Definition *;
iii) Result of performance measurement *;
4) system boundaries:
i) Inputs and outputs of the system as elementary flows;
ii) Decision criteria
iii) Omissions of life cycle stages, processes or data needs *
iv) Initial description of the unit processes;
v) Decision about allocation;
5) data categories:
i) Decision about data categories;
ii) Details about individual data categories
iii) Quantification of energy inputs and outputs *;
iv) Assumptions about electricity production *;
v) Combustion heat *;
vi) Inclusion of fugitive emissions;
6) criteria for initial inclusion of inputs and outputs:
i) Description of criteria and assumption *;
ii) Effect of selection on result *;
iii) Inclusion of mass, energy and environmental criteria (comparisons *);
7) data quality requirements.
Part 3: Scientific background 66 May 2001
In its report, the SETAC-Europe Case studies Working Group (Meier et al., 1997) gives the following
(minimum) reporting guidelines for the Goal and Scope phase:
General study information
- As much detail as possible should be included, i.e. authors, affiliations of authors, commissioning
body, responsible person at commissioning body, availability, etc.
Goal definition
- The overall objectives of the study should be given in a clear and concise statement with the
reasons for carrying out the study and the intended use of the results detailed.
- The methodology employed should be clearly stated and transparent and any differences in
methodology from a full LCA should be explained. All assumptions and value judgements should be
clearly detailed along with the justification for the assumptions.
These reporting guidelines have also been provided by the Working Group in the form of a practitioners’
It might be possible as well as useful to define categories of LCA applications leading to different
choices vis-à-vis methodological procedures and for which different Guidelines would therefore be
applicable. This might result in better and more consistent results, and in more time- and cost-effective
LCA studies.
We recommend following the ISO 14041 requirements, supplemented by the suggestions of Lindfors et
al. (1995a). In this Guide we furthermore distinguish six different types of decision situations:
- global exploration of options;
- company-internal innovation;
- sector-driven innovation;
- strategic planning;
- comparison;
- comparative assertion disclosed to the public.
In the case of comparison of product alternatives, we recommend establishing in the Goal definition step
what differences in results are to be deemed significant for concluding that one alternative is
environmentally sounder than another.
Short-term research
- Definition of categories of applications, with preferred choices of LCA methodology and associated
sets of methodological and procedural Guidelines.
- Standards-setting, possibly by government, regarding the quality and methodology for LCAs for each
of these different applications (i.e. a code of practice for each application).
Part 3: Scientific background 67 May 2001
2.3 Scope definition
In the scope definition step the main characteristics of an intended LCA study are established, covering
such issues as temporal, geographical and technology coverage, the mode of analysis employed and
the overall level of sophistication of the study. A so-called goal and scope report may also be drafted for
the sake of critical review and comments from interested parties. This report should justify all the main
choices with respect to the step ‘Function, functional unit, alternatives and reference flow‘ and