R. Hischier et al., Guidelines for consistent reporting of exchanges from/to nature within life cycle inventories (LCI), INT J LIFE, 6(4), 2001, pp. 192-198
Data availability and data quality are still critical factors for successfu
l LCA work. The SETAC-Europe LCA Working Group 'Data Availability and Data
Quality' has therefore focused on ongoing developments toward a common data
exchange format, public databases and accepted quality measures to find sc
ience-based solutions than can be widely accepted. A necessary prerequisite
for the free flow and exchange of life cycle inventory (LCI) data and the
comparability of LCIs is the consistent definition, nomenclature, and use o
f inventory parameters. This is the main subject of the subgroup 'Recommend
ed List of Exchanges' that presents its results and findings here:
Rigid parameter lists for LCIs are not practical; especially, compulsory li
sts of measurements for all inventories are counterproductive. Instead, pra
ctitioners should be obliged to give the rationale for their scientific cho
ice of selected and omitted parameters. The standardized (not: mandatory!)
parameter list established by the subgroup can help to facilitate this.
The standardized nomenclature of LCI parameters and the standardized list o
f measurement bases (units) for these parameters need not be applied intern
ally (e.g. in LCA software), but should be adhered to in external communica
tions (data for publication and exchange). Deviations need to be clearly st
ated.
Sum parameters may or may not overlap - misinterpretations in either direct
ion introduce a bias of unknown significance in the subsequent life cycle i
mpact assessments (LCIA). The only person who can discriminate unambiguousl
y is the practitioner who measures or calculates such values. Therefore, a
clear statement of independence or overlap is necessary for every sum param
eter reported.
Sum parameters should be only used when the group of emissions as such is m
easured. Individually measured emission parameters should not be hidden in
group or sum parameters.
Problematic substances (such as carcinogens, ozone depleting agents and the
like) may never be obscured in group emissions (together with less harmful
substances or with substances of different environmental impact), but must
be determined and reported individually, as mentioned in paragraph 3.3 of
this article.
Mass and energy balances should be carried out on a unit process level. Mas
s balances should be done on the level of the entire mass flow in a process
as well as on the level of individual chemical elements.
Whenever possible, practitioners should try to fill data gaps with their kn
owledge of analogous processes, environmental expert judgements, mass balan
ce calculations, worst case assumptions or similar estimation procedures.