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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 group’. 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 views, 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 study). - The commissioner of the study shall be stated. - A presentation of the practitioners, including their background, shall be given (an LCA-oriented C.V.). - The purpose shall be clearly and unambiguously stated, in terms of the reasons for carrying out the LCA. - 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 reported. 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’ checklist. PROSPECTS 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. CONCLUSIONS 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. RESEARCH RECOMMENDATIONS 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 TOPIC 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