ILCD Handbook: Framework and requirements for LCIA models and ...

ILCD Handbook: Framework and requirements for LCIA models and indicators First edition
Green arrows: region-specific factors,
Red arrows: substance-specific factors,
Blue arrows: compartment-specific factors,
Black arrows: no specific factors.
Figure 2-1 Example of diagram of the general impact mechanism for the impact category land
use (based on Weidema and Lindeijer, 2001).
This step is necessary to improve transparency, and to make model choices explicit. A
quantitative analysis is made wherever possible, through a method-performance comparison,
enabling the identification of the key differences and aspects that are important in the impact
category.
2.2.2 Development of criteria specific to each impact category
Based on the model analysis and supported by the diagram, a limited number of
additional category-specific sub-criteria are developed under the two criteria: ‗Environmental
relevance‘ and ‗Scientific robustness and certainty‘ (see Table 2-1). This is to supplement
the general criteria and adapt them to the specificities of the impact category. Chapter 2
describes the general recommendations and specific criteria that have been defined for each
impact category.
2.2.3 Methods evaluation and comparison – identification of
key differences
The existing characterisation models are evaluated against the total set of criteria and
sub-criteria (general plus category-specific). A scoring procedure is proposed to evaluate the
characterisation model‘s compliance with each of the criteria:
2 Development and Application of the Criteria for Evaluation 11