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LCA part3

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and uncertainty analysis 5.6
Interpretation
Conclusions and recommendations 5.7
(Well-balanced) conclusions and
recommendations
Part 3: Scientific background 62 May 2001
2. Goal and scope definition
2.1 Introduction
No explicit definition of the Goal and scope definition phase is given by ISO. A definition derived from
ISO’s work might run: The Goal and scope definition is the first phase of an LCA, stating the aim of an
intended LCA study, the functional unit, the system alternatives considered, and the breadth and depth
of the intended LCA study in relation to this aim (see also Figure 2.1.1).
Figure 2.1.1: The Goal and Scope definition phase as part of the general methodological framework for
LCA (source: ISO 14040, 1997E).
The Goal and scope definition anticipates the application, which might be to provide product information
(e.g. by comparing product alternatives), ‘public regulation’ (e.g. product approval based on the results of
comparison with a standard), product or process innovation (e.g. by identifying dominant processes in
the environmental profile to obtain information about the potential effects of innovation) or as a tool for
strategic studies based on policy scenarios. The scope of the study is also established at this stage, as
a function of the time and money available and the intended application. Furthermore, the functional unit
and the products to be investigated are defined. Finally, as in each phase (see Chapter 1), important
issues relating to goal and scope are identified in and reporting guidelines established for each step (cf.
Heijungs et al., 1992).
The Goal and scope definition will largely be the result of discussions between the project
commissioners, the practitioners and those with interests in the study results (interested parties or
stakeholders). The procedural aspects of the goal and scope phase are therefore of particular
importance.
- Product development
and improvement
- Strategic planning
- Public policy making
- Marketing
- Other
Goal
and scope
definition
Inventory
analysis
Impact
assessment
Interpretation
Direct applications:
Life cycle assessment framework
Part 3: Scientific background 63 May 2001
The result of goal definition is an accurate description of the goal and scope of the study, the functional
unit to be used and the (product) system(s) to be investigated.
Thus, the Goal and scope definition phase comprises four steps:
- Procedures (no special section in this Part; see Chapter 1);
- Goal definition (Section 2.2, p. 63);
- Scope definition (Section 2.3, p. 67);
- Function, functional unit, alternatives and reference flow (Section 2.4, p. 76).
Further points of departure for elaborating these Goal and scope definition steps are ISO documents
14040 (1997E) and 14041 (1998E) particularly with regard to the methodological framework and issues
for Goal and scope definition proposed there. In further operationalising the ISO proposals the work of
SETAC Working Groups and relevant proposals by other authors have been taken into due account.
Deviations from ISO have been introduced only when there is significant justification for doing so.
We shall now discuss the substance of each of the last three steps distinguished above, thereby
following the fixed format: Topic, Developments in the last decade, Prospects, Conclusions and
Research recommendations. As explained in Section 1.5, the Procedures step is not discussed
separately in the present chapter but in integrated fashion, for all phases, in Section 1.3.
2.2 Goal definition
TOPIC
In the first step of Goal and scope definition the goal of the LCA study is stated and justified, explaining
the goal (aim or objective) of the study and specifying the intended use of the results (application), the
initiator (and commissioner) of the study, the practitioner, the stakeholders1 and for whom the study
results are intended (target audience). As this step provides the basic starting point for conducting the
LCA study, it should make clear the reasons for undertaking the study. This step is important and
mandatory for each and every LCA study, not only because the stated application will affect the course
of the entire study but also to guarantee clear external communications following completion of the
study (Heijungs et al., 1992).
 
DEVELOPMENTS IN THE LAST DECADE
ISO 14041, clause 5.2 states the following requirement for the goal of the study: “The goal of an LCA
study shall unambiguously state the intended application, the reasons for carrying out the study and the
intended audience, i.e., to whom the results of the study are intended to be communicated.”
Although not formulated as a requirement under the goal of the study, the ISO standards make a
distinction between comparative studies, in particular comparative assertions, and non-comparative
studies. Specific (mandatory) requirements are formulated for LCA studies used to make a comparative
assertion that is disclosed to the public. In ISO 14040 (1997E) a comparative assertion is defined as “an
environmental claim regarding the superiority or equivalence of one product versus a competing product
which performs the same function”.
On several occasions ISO also mentions the importance of realising the possibilities and limitations of
the LCA instrument, both in general and in relation to other environmental assessment tools. Once the
type of application has been determined, it is important to establish whether LCA is the most
appropriate instrument for answering the specific research question, or whether an alternative tool is
 
1 Referred to in ISO 14040 (1997E) as “interested parties”.
Note that recommendations for appropriate design of an LCA project are provided Part 2a, Chapter 1.
These should be duly studied before the actual LCA is commissioned and performed.
Heijungs et al. (1992)
The goal definition in Heijungs et al. (1992) was considered to be part of the overall goal definition. The
overall goal definition referred to that part of the study that established not only the environmental goals of
the LCA study but also its economic, financial, product safety, social (e.g. employment) etc. goals. The ’92
Guide was concerned solely with environmental LCA, as is this guide (cf. Chapter 1). Heijungs et al.
(1992) consequently focused on the environmental reasons for performing an LCA study.
Part 3: Scientific background 64 May 2001
perhaps more suitable for the purpose or may yield relevant additional information. This choice can be
grounded in the possibilities and limitations of LCA in relation to those of other environmental
assessment tools (see also appendix B of the present Part; Wegener Sleeswijk et al., 1996; Finnveden,
1998; Finnveden, 2000; Wrisberg et al., in prep.).
It has become increasingly clear that LCA is but one tool amongst many for environmental analysis. In
some circumstances other instruments may be more appropriate: Risk Assessment (RA), for example,
if siting aspects are crucial to the issue under investigation. Other tools may be used in parallel to
provide better insight into the environmental consequences of a given choice: Substance Flow Analysis
(SFA), for example, if one specific flow is of prime importance in the product system investigated, as in
the case of rechargeable cadmium batteries. The EU-concerted action CHAINET has dealt with this
subject extensively (Wrisberg et al., in prep.).
Other authors support the importance of the aforementioned issues, sometimes usefully expanding them
into more detailed guidelines. For example, Lindfors et al. (1995a) argue that it is not sufficient merely to
define the goal in terms of what is to be done, e.g. ‘To compare the environmental impacts associated
with paints used for wall decoration’, but that the underlying reason, e.g. ‘To provide information in the
setting of criteria for ecolabeling’, also needs to be addressed. They suggest including in the LCA report
a clear statement of the intended