The principles underpinning the computation, such as those relating to emission rates and assumptions about the effects of different variables, are based wherever available on scientific trials in Switzerland. Where such data were not available, data from other countries were used. Where appropriate they were matched with UNECE (United Nations Economic Commission for Europe) recommended values. Data from other countries were, where possible, adapted to suit conditions in Switzerland. Where specific information was not available from the literature, expert judgments were used.
The model is continuously updated and adapted according to current scientific knowledge. To achieve this aim actual results from scientific experiments are a prerequisite. Thus, the outcomes of the studies obtained from the new experimental housing which is under construction at Agroscope INH are required. These studies will include comparisons between housing systems for cattle usual for Switzerland and optimized systems with constructional-technical and organizational emission mitigation options.