PRODUCT ECOBALANCE - A METHOD FOR COMPLET E ASSESSMENT OF, FOR EXAMPLE, BUILDING PRODUCTS MADE OF CEMENT AND CONCRETE

For some years government organizations. industry, and consumer and en vironmental organizations have been working on methods with which, lik e industrial management balances, the environmental burden resulting f rom the manufacture of products are measured and assessed with the obj ect of making products ecologically comparable. Balance models and ter ms with widely differing factual content have been used such as ''ecob alance'', ''product line analysis'' (PLA) or in the American language sphere ''Product-Life-Cycle-Assessment''(LCA). The PLA is supposed to combine and assess all the factors affecting the environment during th e life of a product. The evaluation is intended to extent beyond the e nvironmental sphere and also incorporate economic, social and communal criteria. However no scheme has as yet been agreed for this. Both in the LCA and in the ecobalance the life of the product is described fro m raw material extraction to final disposal within an exactly defined balance framework. On the input side are the consumption of energy, ra w materials, water and air as well as the demands on land The output s ide contains the airborne emissions. the noise immission. the waste ma terial, waste water and waste heat, as well as useful raw materials pr oduced The evaluation is to be confined to environmental demands, howe ver it is only in some respects that it is simpler than that of the co mplex PLA, as at present there is still no generally accepted ''ecolog ical'' calculation unit. In the ecobalance for concrete various enviro nmental units are standardized on the basis of the procedure used by t he Federal Swiss Office for Environment, Forests and Agriculture, and dimensionless proportional numbers are compiled on the basis of actual and maximum possible loadings (limit values). The ecological loading caused by the product is weighed against its benefit to the environmen t in the form of a utility analysis. This decision technique familiar mainly from planning processes makes it possible to include several po ints of view at once arriving at a decision. Differing quantitative, a nd also qualitative, data can be taken into account in the form of wei ghted dimensionless utility values.