Field measurements of odour intensity around a slurry tank and 200-sow swine unit were conducted. Odour intensity from 0 to 3 were defined as none, detectable, strong, and very strong, respectively. The Gaussian plume model was used to back-calculate the odour emission rates from the slurry tank and swine building, and the results were compared to other methods. Wind directions were calculated from odour intensity measurements, which could be applied to identify a prevailing odour source when multiple sources are present.