Air quality is directly related to human well-being. Despite positive trends, with some air pollutants such as NO2 and PM10, it still comes to exceedances of the limit values for the protection of human health. A reliable tool for the modeling of the distribution of air pollutants is therefore all the more important.
For this purpose, IMMI provides two dispersion models: a simple Gaussian model and a long range particle model according to VDI 3945, page 3, which is in the form of the reference implementation of the Federal Environmental Agency AUSTAL2000. Within this tool, a variety of pollution legal tasks can be realized, such as the monitoring of the spread of dust at construction waste recycling plants or odor immission forecasting in the environment of farms.
I. Lagrangian air dispersion model – AUSTAL2000
IMMI's comfortable data editing and mapping features are used with the official German implementation of the Lagrangian model compliant with VDI 3945-3. IMMI acts as the user interface whereas AUSTAL2000 is used as the Lagrangian CPU core. The development of this common CPU core was funded by the German government in order to have a single unified code compliant with Annex 3 of the German Technical Instructions on Air of 2002 (TA-Luft 2002). TA-Luft 2002 and AUSTAL2000 are central elements of the German transposition of the European Air Quality Directive and daughter directives. All data transfers between IMMI and AUSTAL2000 are automatically managed and remain perfectly transparent to the user, who never interacts with the CPU core directly. The whole digitizing of the project is done, as usual, in IMMI. All GIS functionality, all functions and commands to enter and edit data as well as all features to present and export calculated results can be used.
II. General-purpose Gaussian model
IMMI – the universal environmental pollution software – features a fully operational Gauss model in its base module. The model is based on the tried and tested German TA-Luft, Annex C of 1986.