Intensity is measured on a scale of 0 to 5 where 0 has no perceivable odor and 5 has an extremely strong odor. Intensity levels are determined by comparing to a reference odorant, n-butanol.
Hedonic tone is the pleasantness or unpleasantness of an odor.
Eight trained panelists are used to evaluate each odor sample. The panelists are required to follow strict rules in order to have their senses in top form.