A review on the use of air dispersion models for odour assessment

Only recently have unpleasant odours become an important environmental issue and a specific legislation is being developed and implemented. The assessment of odour impact involves several different aspects (large number of odorants, human sensitivity, different perception thresholds, etc.) and it is dealt with by the application of different techniques and methods. In this paper a review about the reliability of air dispersion models applied to odour impact assessment determined by different type of sources is presented, based on the analysis of 69 case studies published over the last 10 years. The Gaussian models were the most used technique (67% of case studies) often accompanied with results validation with experimental data. The analysis of the case studies and related validation processes highlighted the reliability of dispersion models if some critical issues, such as the presence of particular climate conditions, duration of averaging times and position of important receptors, are known and correctly managed.