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In principle, the proposed methodology does not need a complete LCI analysis
with ISO 14041 as a basis. What it really needs is life-cycle inventory data about
the process chain under study. These data can also be obtained by streamlined LCAs
or simplified LCI approaches (Curran and Young, 1996). An important part of such
methods is an iterative screening procedure (Fleischer and Schmidt 1997), which
includes elements similar to those used in the methodology presented in this study
by way of an iterative dominance analysis in order to identify the priorities. Evi-
dently, a dominance analysis can also be applied directly in the LCI analysis during
data collection (see Figure 6.10).

6.5.4 LIFE-CYCLE IMPACT ASSESSMENT METHODS
In the step following the ISO 14040 framework for LCA, one or more life-cycle
impact assessment methods are applied to the LCI results. In the goal and scope
definitions, the LCIA methods were selected. In Figure 6.11, an overview of the
usage of life-cycle impact assessment methods is given; the main options are shown
schematically:

• Midpoint potentials (e.g., GWP and HTP)
• Midpoint-based weighting methods (e.g., eco-indicator 95 and EDIP)
• Direct weighting methods (e.g., Tellus and EcoScarity)
• Endpoint-orientated methods (e.g., eco-indicator 99 and EPS)

More details about these methods can be found in Chapter 3.
The global indicators selected in the weighting scheme are considered separately.
They are obtained in the characterization step in both options in which midpoints
are calculated. Each global indicator feeds directly into the damage profile. If
required, they are first monetized by abatement costs.
The midpoint-related LCIA methods allow calculating the environmental poten-
tial of the respective impact category in the characterization step. All presented LCIA
methods except the midpoint potentials permit obtaining a single index to measure
the environmental impact performance. The midpoint-based weighting methods
require carrying out normalization and then a weighting step. Direct weighting
methods omit the characterization and the normalization step. As endpoint-orientated
method, eco-indicator 99 (see Chapter 3 for further details) does not contain explic-
itly midpoint results.
The results of the LCIA methods are called impact scores in Figure 6.11. These
scores allow comparing the situations or scenarios on a midpoint level or endpoint-
orientated level, but not in the most accurate way that is still feasible with regard
to actual impacts and the consideration of spatial differentiation. Therefore one or
more selected impact scores are used in a dominance analysis in order to estimate
in more detail the environmental damages of the main processes and pollutants in
the studied process chain.

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