The possibility of applying gas chromatograph to air samples discrimination in regard to odour intensity and hedonic quality was examined. The air samples were arornatised with lemon oil and four admixtures. fourteen distinctive points of a chromatogram were appointed and the distances from the points lo a set basis were measured. The set of h 1-h 14 parameters (inputs) and varied individual sensory estimations of I and H (outputs) was used as a training data set for NN. Possibility of discrimination of the odour quality of the samples situated close to the threshold of odour quality difference detectability was confirmed on the level of approximately one.

550 individual odour intensity (S) assessments of 62 samples of air polluted with 2-propanol were collected (concentration c = 46-2 1000 mg/m3). The data were used to establish odour detection threshold of 2-propanol by extrapolation to S = 0 in the coordinate system of S-log c. The obtained values were compared with triangular tests results and data published in the literature. A reason for apparent positive deviations from Weber-Fechner law within a range of low odour intensities was indicated,