The odour emission inventory for a plant, derived from the sampling and testing of odour samples, is used as input data for atmospheric dispersion modelling. This modelling is able to predict ground level odour concentrations in the vicinity of a plant.

The Odour Unit operates a suite of dispersion models, including AUSPLUME, Auspuff and ISC-Prime. Odour modelling results are typically presented as odour contour plots, overlaid onto an aerial photo or topography plan.

Modelling results are validated using field odour assessment data gathered using ambient odour intensity readings downwind of the source (see Community Consultation and Impact Assessment).