Odour complaints represent a large number of the complaints centred around intensive swine production units. Previous studies have shown a correlation between odour and aeresol particles from dust buildings but three fundamental questions till need to be answered: what types of compounds make dust unpleasant? How much odour does it carry? What sizes of particles carry the most odour? Through the use of gas chromatography results show there are aprroximately 70-100 volatile compounds absorbed on dust, as well shows similar compounds between grower and finisher units with respect to peak retention time. These componds are similar in winrter and summer months, however their peak retention time varies between seasons. As well, the study indicated all rentention times of all major compounds was less than 22 minutes, indicating that indolic compunds are not associated witrh dust or feed.