In a decade, prediction of microbial mass dispersion in the case of biological weapon attack is modeled by several authors. The model persented in this study is a comuter program based on diffusion-dispersion theory. By use of this program, a multisource model, instantaneous and continuous source models and also microorganism die-off due to environmental factors (desay constant) can be examined. A 2000 × 2000 m² field is considered to from meteorological and laboratory sources. Atmospheric stability, humidity and irradiation intensity is also considered. Downwind respirable viable cells (Pathogens) and non-viable cells (Allergens) are calculated.
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