Inventory of the processes

The standard Eco-indicators 99 have been based on the energy database developed by ESU-ETH in Zürich [ESU 1996]. Also, data from the SimaPro LCA software tool (see www.pre.nl web address) have been used. In the inventory of such data it is very important to use a consistent methodology concerning items like:

• System boundaries (what is to be included in analysis).

• Allocation (how to deal with industrial processes that produce more than one output).

• Regional aspects (Ie-99 uses Dutch, Swiss or average European data).

• General data quality issues. A brief description of such these issues follows.

Also, Eco-99 recommends that that users of their methodology do not mix their database with indicators that have been developed by other methodologies.

Uncertainties

Two types of uncertainties are noted in the methodology that is used to calculate the indicators:

• Uncertainties about the correctness of the models used.

• Data uncertainties.

The first type includes value choices like the choice of the time period of to be used in the damage model, or whether to include a particular effect when there is not as yet sufficient scientific proof of its environmental impact . The data uncertainties refer to difficulties in measuring or predicting effects. This type of uncertainties is relatively easy to deal with and can be expressed as a range, or a standard deviation from the reported value.

Uncertainties about the correctness of the model

These uncertainties are very difficult to express quantitatively. In debates about the seriousness of environmental effects opinions are usually very diverse, even when the evidence is overwhelming (e.g. the global warming effect). This is due to differences in economic interest, knowledge level, or fundamental differences in attitude (e.g. anthropocentric vs biocentric views of the Earth). Some people would argue that long-term effects are very important, while others believe that in the long-term new ways will be found to solve the environmental problems of future generations.

Such differing perspectives are also present in the economic system. For example, many people believe that the money they earn is due only to their hard work and not at all to the society in which they have thrived; therefore, there can be no societal claim to a fraction of their income in the form of taxes. The developers of Eco-indicator 99 were also confronted with model choices that are dependent on such different perspectives. To simplify matters, they used three “archetypal” perspectives that are representative of the principal perspectives in public with respect to the environmental system:

The three “archetypes” in Eco-indicators 99

Type	Time perspective	Ability to manage	Required level of evidence
Hierarchist (I)	Balance between short and long term	Proper policy can avoid many problems	Inclusion is based on consensus
Individualist (I)	short term	Technology can avoid many problems	Include only proven effects
Egalitarian (E)	long term	Problems can lead to catastrophy	Include all possible effects

The Ei-99 “Archetypes” were taken from the Cultural Theory framework (Thompson 1990 and Hofstetter 1998), and are frequently used in social science. This theory does not imply that there are just three types of people; the three archetypes are conceptual models that most people use to some degree in their daily life (e.g. an egalitarian in public life may very well be a hierarchist at home). The Eco-indicator 99 methodology presented here is based on the Hierarchist (H) type that is considered by Eco-99 to be the default perspective . However, the full Eco-99 LCA software provides data for the other two types so that LCA modelers can assess the influence of the other two types on the result of the LCA.