Page 187 - Materials Chemistry, Second Edition

10 Life Cycle Impact Assessment 173

LCIA method (or several) available in the version of the LCA software that the
practitioner has access to.

External factors for this choice will be among other:
• Requirements following from the defined goal (see Chap. 7) and specified in the
scope definition of the LCA (see Chap. 8)
• Requirements by the commissioner of an LCA
• Fixed requirements, e.g. for Environmental Product Declarations (EPDs) or
Product Environmental Footprints (PEFs) from underlying sector-based Product
Category Rules (PCRs) or from labelling schemes (see Chap. 24)

Practical constraints may, for example, consist of:
• Availability, completeness and quality of LCI results required for a specific
impact category
• Availability, completeness and quality of characterisation models and factors for
a specific impact category, including the need to consider specific rare or new
impact categories, such as noise, which may only be supported by one or two
LCIA methods if at all
• If normalisation is required, availability, completeness and quality of normali-
sation factors for a specific impact category or LCIA method
If practical constraints prevent the practitioner from including what has been
identified as relevant impact categories, this needs to be made clear in the dis-
cussion and interpretation of the LCA results and comments need to be made on
whether it may change the conclusions. In the illustrative case on window frames in
Chap. 39, the method recommended for characterisation by the International Life
Cycle Data system (ILCD) is chosen as life cycle impact assessment method
(EC-JRC 2011), and all impact categories covered by the method are included in
the study.
In common LCA practice, a number of category indicators, based on specific
characterisation models is combined into predefined sets or methods, often referred
to as life cycle impact assessment methods or simply LCIA methods (EC-JRC
2011; Hauschild et al. 2013), available in LCA software under names such as
ReCiPe, CML, TRACI, EDIP, LIME, IMPACT 2002+, etc. However, with an
increasing number of LCIA methods and indicators available, the task of choosing
one requires a tangible effort from the practitioner to understand the main charac-
teristics of these methods and to keep up-to-date with the developments in the field
of LCIA. A qualitative and comparative overview of the main characteristics of
current LCIA methods can be found in Chap. 40 of the Annex of this book.

10.2.1.1 How to Choose an LCIA Method?

A number of LCIA methods have been published since the first one appeared in
1984. Figure 10.1 shows the most common methodologies published since 2000