The Effect of Panel Selection on Odor Index Calculation

Abstract

The odor index used in regulations under the Offensive Odor Control Law in Japan is calculated based on the measurement results of odors taken by human olfaction. To reduce dispersion and improve accuracy in the calculation of the odor index, the value is determined based on measurements conducted by multiple panels and repeated tests. In this study, we quantitatively analyze the effect of panel selection on the odor index using a probabilistic method (CDE method). Assuming that the panel’s olfactory ability follows a log-normal distribution, probable hits are considered, and intra-individual variability does not occur, we calculated the odor index by varying the number of panel members and by restricting panels to those with a certain level of olfactory ability. The results of these calculations suggest that increasing the number of panel members, conducting measurements across multiple institutions, and excluding panels with low olfactory abilities are effective in reducing the variability of the odor index.