Goal definition and scoping

Goal definition and scoping is the initial step of a LCA. It determines the purpose of the study, the scope, the functional unit and a procedure for quality assurance of the result (Figure 4.3). Sources for the data to be entered into the analysis should be identified, as should the type of impacts to be evaluated in the impact assessment. 

Figure 4.3 Goal definition and scoping determines the object and depth of the study, and the application of the results.

A formal LCA comprises four steps goal definition and scoping, inventory analysis, impact assessment, and interpretation. Figure 2.6 illustrates the process with respect to a material or mass balance, omitting the components of energy balance. Each step is described briefly below [2,93,97,98] as it would be applied to a product or process rather than a service, and with a focus on mass inputs and outputs rather than energy, noise, or other considerations sometimes taken into account in LCA. 

Goal definition and scoping Defining the functional unit, scope of the LCA, and the system boxmdary identification. 

In goal definition, the scope and purpose of the LCA is defined. The functional unit and system boundaries are also established. The functional unit is the reference point to which environmental impacts are attributed. The choice of functional unit depends on the application of the LCA. For a process it could be a tonne of product or feedstock, or a tonne of impurity removed. For a commodity product the functional unit could be a tonne of product, but for specialty chemicals and most consumer products performance properties are more important and the choice can become complex. For example, performance of a paint would be related to its surface coverage and durability hence a possible functional unit for the paint might be the quantity required to cover a square meter of surface over a time span of 20 years. 

Life cycle assessment is defined by ISO 14040 as compilation and evalu ation of inputs, outputs and the potential environmental impacts of a product system throughout its life cycle. The ISO standards regulate the procedural aspects of LCA. They do not, however, provide all the information required for carrying out an LCA study. The main phases of LCA are goal and scope definition, inventory, impact assessment, and interpretation. The various applications of LCA are not regulated by the standard (Fig. 15.1). 

The goal and scope definitions inform the reader of the intended use of the study, including... 

ISO, F.nvironmental Management—Life Cycle Assessment—Goal and Scope Definition and Inventory Analysis (ISO 14041). 

Goal and Scope Definition. This phase deals with the selection of system boundaries and the setting of the functional unit which describes the primary function(s) fulfilled by a (product) system and can be used as a basis for the comparison of alternative systems. ... 

Life Cycle Interpretation. The results obtained within the Life Cycle Inventory and/or the Life Cycle Impact Assessment are interpreted in the light of the Goal and Scope Definition (e.g., by means of sensitivity or uncertainty analyses) in order to draw conclusions and make recommendations. ... 

ISO 14041 1998 (1998) Environmental Management - Life Cycle Assessment - Goal and Scope Definition and Life Cycle Inventory Analysis. European Commitee for Standardisation, Brussels, Belgium. 

In the first stage of the LCA analysis, it is necessary to define the objective and the scope of the paper before the actual start [35]. The study goal and scope definition determine the next procedure character and the circumstances in which the study outputs are valid [32]. [36] requires to establish a study goal and scope while the study scope means to determine the product system, the functional unit and system boundaries, to determine allocation rules, the assessment methodology, hypothesis and limits and data quality. 

Rebitzer G, Ekvall T, Frischknecht R, Hunkeler D, Norris G, Rydberg T, Schmidt WP, Suh S, Weidema BP, Pennington DW. Life Cycle Assessment Part 1 Framework, Goal and Scope Definition, Inventory Analysis, and Applications. Environment International. 2004 30(5) 701-720. DOI 10.1016/j.envint.2003.11.005... 

Goal and scope definition, where the goal of the study is defined, the eventual alternatives that will be considered are given, the system boundary is determined and the processes within the product- or service-system are defined. 

ISO (1998) ISO 14041 Environmental management - Life cycle assessment - Goal and scope definition and inventory analysis. International Organisation for Standardisation, Geneva... 

An LCA typically starts by defining the goal and scope of the study. The goal and scope definitions are important since they define the level of detail in the study. The exact question to be answered using the LCA method is... 

The goal definition element of an LCA identifies the purpose for the study and its intended application(s). This step will present reasons why the study is being conducted and how the results will be used. Scoping defines the boundaries, assumptions, and limitations of a particular LCA. It defines what activities and impacts are included or excluded and why. Scoping should be attempted before any LCA is conducted to ensure that ... 

The goal-and-scope definition process is an integral part of any LCA study. At the outset of an LCA, before any data are collected, key decisions must be made regarding the scope and boundaries of the system being studied. These decisions are mainly determined by the goal, i.e., the defined reasons for conducting the study, its intended applications, and the target audience. 

This step is difficult since the results have to be interpreted, and the interpretation will be subjective. For example, what is more important—the environmental burden of acidification or global warming To answer these questions, the goal and scope definition must have been given proper care. 

ISO International Standard 14041, 1999E. Environmental management—life cycle assessment—goal and scope, definition and inventory analysis. International Organization for Standardization (ISO), Geneva. 

Scoping and goal definition is often thought of as the most important process of an LCA, and care must be taken to establish appropriate boundaries that are consistent with the objectives of a study. Suh et al.102 warn that including a scientific basis for excluding and including processes in system boundaries is essential and emphasizes the difficulty in... 

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