Tunnel ventilation of swine buildings conveys odourous dust and gases out of the production buildings. Measurement of dust and odour levels and other environmental parameters is necessary for characterizing emissions and evaluating control options. During evaluations of odour control systems, measurements of dust and odour levels in building inlet and exhaust air were obtained. Odour and dust levels were consistent with data obtained in other states and Europe. Odour concentrations and emission rates were based on odour measurements from the Duke University Taste and Smell Laboratory at several dilution levels, as well as a calibration curve for odour panelists based on swine manure odour. The computed odour concentration based on measurements over a range of dilutions was greater than the predicted odour concentration based on the calibration curve, for two field visits. This result may be due to odourous dust particles increasing odour persistence above that of vaporous odourants from swine manure. Odour measurements were also obtained using headspace sampling of unaspirated and aspirated cotton swatches. Aspirating the swatches increased odour intensity compared to unaspirated swatches and improved correlation with air sample odour intensities.