The results presented are not from agricultural application. However interesting information is given on the quality assurance in olfactometry and on the factors that have to be considered to analyse an odour situation. Emphasis has been put on the odour measurement of the threshold level but the psychophysical dose-effect relationship are not linear (odour unit vs. odour strenght). To have a complete ideal of the odour, odour quality and acceptability has to be of prime importance as those two factors give information that is not only perceptual but also related to social values. These factors have to be known as the perception of odour plays an important role in the generation of odor annoyance.
To improve the validity of odour measuments, a calibrated scale should be used to to able to compare the results.

Interesting elements are given to help make a link between factors (odour level, intensity and acceptability) that have to be measured and odor annoyance.