 Eco-indicator
95 Designers need some yardstick to measure the
environmental impact of a material or process.
The Eco-indicator 95 was
developed to provide such tool, and was one of the first to express the total environmental load of a material or process
in a single score.
Introduction Design for Environment is still a popular concept to attempt to develop more environmentally sound products. But what is the environment, and how to bring it behind a drawing board or CAD computer? Until the Eco-indicator 95 was developed, no unambiguous measure for the environmental impacts of products was available. This made it difficult to develop environmentally sound products. For Philips, NedCar, OCé and Schuurink, this prompted the request to the Dutch government to start the Eco-indicator project. In the Eco-indicator project, a life cycle impact assessment method was developed by PRé Consultants. This was done in close collaboration with industry, the universities of Amsterdam, Leiden and Delft as well as consultancies TNO and CE.
back to top 100 Eco-indicator scores In the project, a 100 Eco-indicator 95 scores for common materials and processes were calculated. The application and the backgrounds of the method are briefly described on this page, the full reports can be downloaded. An update (January 97) is available. In 1999, the successor of the Eco-indicator 95 became available: the Eco-indicator 99. Many companies have now started to use the Eco-indicator as a tool in environmentally sound product development. back to top Ecodesign with Eco-indicators Every product has impacts on the environment. Raw materials have to be extracted, the product has to be manufactured, distributed and packaged. Ultimately it must be disposed of. Environmental impacts often occur during the use phase of a product because the product consumes energy or material itself. Thus, if we wish to assess a product's environmental impact, all its life cycle phases must be studied. An environmental analysis of all the life cycle phases is called a Life Cycle Assessment (LCA) or Life Cycle Analysis. A Life Cycle Assessment can be used in two ways: 1. To determine the total environmental impact of products or design alternatives with the aim of comparing them. For a designer, an LCA can provide information if he has to choose between design alternatives or between different components or materials.
2. To determine the most important causes of a product's environmental impact. A designer can concentrate to achieve improvements on these first.
A designer wishing to use Life Cycle Assessments in the design process has been faced by two major problems: - The result of a Life Cycle Assessment was difficult to interpret. Within an LCA it is possible to determine the contribution of a product life cycle to the greenhouse effect, acidification and other environmental problems, while the total environmental impact remains unknown. The reason is the lack of mutual weighting of the environmental effects.
- In general, the careful collection of all the environmental data in a product's life cycle is complex, expensive and time consuming. As a result extensive LCAs cannot usually be carried out during a design process.
back to top The Eco-indicator project has resolved these problems as follows: 1. The LCA method has been expanded to include a weighting method. This has enabled one single score to be calculated for the total environmental impact based on the calculated effects. We call this value the Eco-indicator score. 2. Data have been collected for most common materials and processes. Eco-indicator scores have been calculated from these data. The materials and processes have been defined such that they fit together like building blocks. Thus, there is an indicator for the production of a kilo of polyethylene, one for the extrusion of a kilo of polyethylene and one for the incineration of a kilo of thermoplastics. The Eco-indicator of a material or process represents the total environmental impact of a material or process, based on data from a Life Cycle Analysis. The higher the indicator, the greater the environmental impact. The Eco-indicator brings environmental assessments within the designer's reach. back to top
Application of the Eco-indicator tool The application of the Eco-indicator is quite simple. A designer must list the amounts of materials, energy and processes that occur during the life cycle of a product. Then look up the Eco-indicator scores for these materials and processes, and multiply the amounts with the corresponding Eco-indicator score. When this is done one can analyze which processes contribute most to the overall effects. The next step is to look for alternative design solutions and analyze whether these alternatives are indeed preferable from an environmental point of view. In the figure below the results of an analysis of a coffee maker are presented. The size of the boxes indicate the Eco-indicator score of the process or material. It is clear that the electricity use and the paper filter use are dominating. This means a designer has to consider ways to reduce the use of paper and electricity first. One option could be the use of a thermos jug, since this would eliminate the use of electricity to keep the coffee warm. He can now calculate the environmental burden of the production of the jug and analyze how this balances with the reduced use of electricity.  Figure 1: The coffee machine process tree, where the size of the process blocks is proportional to the relative importance of the process. back to top Calculation of Eco-indicators A crucial aspect of the Eco-indicator is the transparency of the calculations. This is needed to understand the meaning of the indicator and to be able to compute new indicators when needed. The Eco-indicator 95 is described in a report that can be downloaded. The method is available in SimaPro. The Eco-indicator project has kept as close as possible to the methodology of the life cycle assessment (LCA) method as described by SETAC and CML. This is an important starting point because an analysis using the Eco-indicator method is intended to provide the same result as an LCA as far as possible. This starting point means that the method's initial phases are the same as the LCA steps: back to top Inventory phase
Within the project 100 LCA's have been drawn up (or existing ones have been revised). This means that all the relevant processes have been analyzed and all emissions have been collected to form an impact table, a total overview of emissions. Classification
A number of environmental effects have been calculated on the basis of the impact table. Classification enables the environmental effects of two products to be compared. For this the presentation as shown in figure 2 is often used. This figure illustrates a comparison between a paper and a plastic bag.
 Figure 2: Example of a comparison between a plastic and a paper bag. The highest score for each effect is set at 100%. Up to this point the Eco-indicator follows the classic LCA method. However, in this example the result proves to be difficult to interpret. The paper bag causes more carcinogenic substances, but has a better score on the other environmental effects. Thus the LCA does not reveal which is the better bag. What is missing is the mutual weighting of the effects. Although the LCA method describes how this should be done, the weighting step is almost never carried out because of a lack of data. The Eco-indicator project has plugged this gap. back to top Normalization and evaluation Based on figure 2 it is hardly possible to decide which bag is more environmentally friendly. In the first place this is because the higher of the two scores is scaled to 100%. In reality this is a meaningless scale. A score of 100% can represent a very small or a very large emission. The first step in any further interpretation consists of comparing the scores with another score. In LCA terminology this is called the normalization step. In our project we developed an inhabitant equivalent for the normalization step, i.e. the environmental effects that an average European person causes in one year. The scores of the first step are normalized to the average European, as shown in figure 3. The effects are now compared on the scale of inhabitant equivalents. From this it becomes apparent that the scores for ozone layer depletion, eutrophication, pesticides and carcinogens are very low in absolute terms. The two smog scores and the scores for acidification, heavy metals and the greenhouse effect are relatively high.
 Figure 3: The effect scores from figure 2 are normalized here to the effects that an European person causes in one year. 1000 bags thus cause a 0.003rd part of the greenhouse effect that this person causes in one year. Normalization reveals which effects are large and which are small in relative terms. However, it does not yet say anything about the relative importance of the effects. A small effect can very well be the most important. A weighting step is therefore necessary to achieve an overall result. This step has been carried out in figure 4. The weighting factors used in this last step are discussed in the following paragraph. All effects are now scaled to a certain measure of seriousness. In this example the seriousness is indicated in Eco-indicator points.
 Figure 4: The evaluation step: weighted normalized effect scores. If all the columns are plotted along the same scale, the column lengths (Eco-indicator points) can in principle be totaled. This has been done in Figure. 5. It now becomes clear that the paper bag is somewhat less environmentally friendly, although the difference is minor.
 Figure 5: After weighting the column lengths can be summed. The paper bag shows a slightly greater environmental impact than the plastic bag. However, the difference is so small that given the uncertainties no hard conclusion is possible. back to top
Backgrounds to weighting Based on these graphs the weighting of effects seems to be very straightforward. The problem, of course, lies in determining the weighting factors. Much consideration has been given to this subject in the Eco-indicator project. After detailed analysis of the options the so-called Distance-to-Target principle was chosen for determining the weight factors. This principle has already been in use for some years in the Swiss Ecopoints weighting system. The underlying premise is that there is a correlation between the seriousness of an effect and the distance between the current level and the target level. Thus if acidification has to be reduced by a factor of 10 in order to achieve a sustainable society and smog by a factor of 5, then acidification is regarded as being twice as serious; the reduction factor is the weighting factor. This principle has been refined and improved in the project, but there is insufficient space to detail the improvements here. Please read the final report if you want to know more. The term "target level" still embodies a major problem. What is a good target level, and how can such a level be defined? The above-mentioned Swiss Ecopoints method uses political target levels from government policy papers. These levels are often defined on the basis of a compromise between feasibility (cost) and desirability. In the Eco-indicator project it was decided to define target levels that are independent of politics and are based on scientific information. The problem then arises again that scientists have different views on what constitutes a good target level, because different environmental problems cause different types of damage. Smog, for example, results in health complaints, while acidification causes major damage to forests. To ensure that the target level for acidification is equivalent to that for smog a correlation must be established with the damage caused by the effect. The premise is that the target level for each effect yields uniformly serious damage. The following damage levels are assumed to be equivalent: - The number of fatalities as a consequence of environmental effects. The level chosen as acceptable is 1 fatality per million inhabitants per year.
- The number of people who become ill as a consequence of environmental effects. This refers in particular to winter and summer smog. The acceptable level set is that smog periods should hardly ever occur again.
- Ecosystem degradation. A target level has been chosen at which "only" 5% ecosystem degradation will still occur over several decades.
back to top Setting equivalents for these damage levels is a subjective choice that cannot be scientifically based. It is therefore also possible to make different assumptions which could cause the weighting factors to change. The current choice came about after consultation with various experts and a comparison with other systems, including the Swedish EPS system. Figure 6 is a schematic representation of the Eco-indicator principle:  Figure 6: Eco-indicator weighting principle To establish a correlation between these damage levels and the effects a detailed study was carried out of the actual state of the environment in Europe. Determined were the current status of each effect, as well as by what degree a particular effect has to be reduced to reach the damage level defined for it. Much work has been carried out particularly by the Dutch National Institute for Public Health and Environmental Hygiene (RIVM) in this field. Detailed maps of Europe are now available in which the environmental problems are shown in a high degree of detail. These data were used to determine the current level of an environmental problem and by what factor the problem must be reduced to reach an acceptable level. The following table lists the weighting factors and the criteria applied:
|
Environmental effect |
Weighting factor |
Criterion | |
Greenhouse effect |
2.5 |
0.1 C rise every 10 years, 5% ecosystem degradation | |
Ozone layer depletion |
100 |
Probability of 1 fatality per year per million inhabitants | |
Acidification |
10 |
5% ecosystem degradation | |
Eutrophication |
5 |
Rivers and lakes, degradation of an unknown number of aquatic ecosystems (5% degradation) | |
Summer smog |
2.5 |
Occurrence of smog periods, health complaints, particularly amongst asthma patients and the elderly, prevention of agricultural damage | |
Winter smog |
5 |
Occurrence of smog periods, health complaints, particularly amongst asthma patients and the elderly | |
Pesticides |
25 |
5% ecosystem degradation | |
Airborne heavy metals |
5 |
Lead content in children's blood, reduced life expectancy and learning performance in an unknown number of people | |
Waterborne heavy metals |
5 |
Cadmium content in rivers, ultimately also impacts on people (see airborne) | |
Carcinogenic substances |
10 |
Probability of 1 fatality per year per million people | This table reveals that high priority must be given to limiting substances causing ozone layer damage and the use of pesticides. The latter is becoming a very serious problem in the Netherlands in particular. Furthermore, a great deal of consideration must be given to the diffusion of acidifying and carcinogenic substances. It is apparent from the table that a number of effects that are generally regarded as environmental problems have not been included. The reason for omission of a number of effects is given below: Toxic substances that are only a problem in the workplace
Many substances are only harmful if they occur above a certain concentration. Such harmful concentrations can occur relatively easily in the workplace, while the concentration outside often remains very low and well below the damage threshold. This happens because the substances are generally diluted to a large extent and because many substances disappear from the atmosphere because of natural decomposition processes. Only substances that actually are found in harmful concentrations are included in the Eco-indicator, while the rest are disregarded. This means that a product with a low Eco-indicator score can still cause poor working conditions because substances are released that are harmful locally.
back to top Exhaustion (depletion) of raw materials
If a product made of very rare raw materials is used this rarity is not expressed in the indicator; after all, the fact that a substance is rare does not cause any damage to health. The emissions arising from extraction of the raw materials are included and are usually extensive because ever lower-grade ores have to be used. Incidentally, the term "exhaustion" is very difficult to define. Alternatives are available for most raw materials, and recycling could enable raw materials to remain in circulation for much longer. In fact minerals never disappear from the Earth; at worst they are diffused in an unfortunate manner. back to top Waste
The fact that waste occupies space is not particularly important in environmental terms because the amount of ecosystem lost to the mountains of waste is relatively small compared with the damage to ecosystems caused, for example, by acidification. However, the substances released by waste (heavy metals, or CO2 on incineration) are very important. These latter effects are included in the indicator, but the quantity of waste in itself is not part of the assessment process. As a result of these differences the Eco-indicator can be seen as an indicator of emissions, and raw materials depletion and the use of space by waste must be evaluated separately at present. back to top Conclusion The Eco-indicator is primarily a tool for the designer. It allows the designer to make his or own own LCA screenings with the help of 100 pre-defined "LCA
results", which are called Eco-indicator scores. The designer can use the Eco-indicator in two ways: - To get the questions right (what are the primary causes of the environmental burden of a product)
- To get the answers right (which design alternative has the lowest environmental burden)
For LCA specialists, the methodology is an extension of the SETAC LCA methodology. It uses a normalization and an evaluation stage. The evaluation or weighting is based on the best available knowledge of the environmental damage of effects on a European scale. back to top Bibliography 1. Ahbe S. et al. Methodik für Oekobilanzen [Method for Environmental Life Cycle Assessments], BUWAL, publication 133, October 1990, Bern, Switzerland. This report (in German) describes the development of the Swiss Ecopoints weighting method. 2. Goedkoop M.J.; Demmers M.; Collignon M.X.; The Eco-indicator 95, Manual for designers; NOH report 9524; PRé consultants; Amersfoort (NL); July 1995; ISBN 90-72130-78-2. This report describes the application of the Eco-indicators by designers. It does not require any knowledge on LCA. 3. Goedkoop M.J.; The Eco-indicator 95, Final report 4. Goedkoop M.J.; Cnubben P; De Eco-indicator 95 bijlage rapport (annex report); NOH report 9514 A; PRé Consultants; Amersfoort (NL); July 1995, ISBN 90-72130-76-6 (only available in Dutch). 5. Heijungs R. (final editor) et al; Environmental life cycle assessment of products, Guide and Backgrounds, NOH report 9266 and 9267; Leiden; 1992; commissioned by the National Reuse of Waste Research Programme (NOH), in collaboration with CML,
TNO and B&G. This is the widely used guide for LCA practitioners. 6. RIVM, The environment in Europe: A global perspective, Sept. 1992, ISBN 90-6960-031-5. This report describes most of the environmental damage caused by environmental effects. 7. SETAC, Society of Environmental Toxicology and Chemistry, Guidelines for Life-Cycle Assessment, a 'Code of Practice', Brussels, Belgium, 1993. This is a general description of the basic principles of LCA 8. SimaPro, Life Cycle Assessment software and database, includes the Eco-indicator 95 methodology, PRé Consultants, Amersfoort, The Netherlands. A good introduction to the LCA methodology is: Beginning LCA, A guide into environmental Life Cycle Assessment, NOH report 9453.
For more detailed information: Environmental Life Cycle Assessments of Products, Guide and Backgrounds, NOH report 9266 and 9267 or
"Code of Practice", SETAC Society of Environmental Toxicology and Chemistry, Guidelines for Life-Cycle Assessment, Brussels, Belgium, 1993. back to top |
