Diesel Exhaust Offensive Effect – True Odor or Irritancy?

Human nose sensory properties call out two different nervous systems: the true olfactory system transfers actual olfactory information and the trigeminal system transfers irritancy. Both present specific properties and play their part in the offensive effect felt by the population and measured by a conventionnal nose panel. By using a novel olfactometer sensitive only to true olfactory excitation and not to trigeminal excitation, it is possible to afford an explanation for the lack of correlation between nose panel data and DOAS data. The irritant aspect of Diesel exhaust fumes seems thus to play a leading part in the sensory offensiveness.