TNO Experience with Olfactometry

Publisher Summary This chapter discusses several aspects of the TNO experience with respect to olfactometry. Odor concentration measurements are taken by diluting an odorous air sample with odor-free air and offering the dilutions to a panel of test subjects. The number of dilutions is expressed as a dilution number, being the quotient of the diluted volume and the original volume. The dilution number at which half the panel can no longer distinguish the diluted odorous air from odor-free air is then, by definition, the numerical value of the odor concentration. For odor samples consisting of a single compound or of a simple mixture of some compounds, it is possible to quantify the odor concentration by chemical determination. This method involves measuring compound concentrations by means of instrumental analysis and then calculating the odor concentrations based on the odor thresholds of the separate compounds. The method of the working of “TNO Sniffing Car” is discussed. It couples a high accuracy with a high sensitivity.