The international standard EN 13725 allows two different modes to be used for determination of odour-concentrations. Both modes are assumed to yield equal results. To verify whether this assumption is correct, a comparison have been carried out. In the experimental design, the nAFC mode was fully implemented using a 2AFC procedure. To prevent from adverse effects on the panellists’ performance, the yes/no mode was performed without presentation of blanks. No main effect of method was established (p > 0.10). Furthermore, there is a tendency that odour concentrations obtained with the yes/no method are slightly higher than those obtained with a 2AFC-method.
