THE FREQUENCY OF ODOR EVENTS AS A MEASURE OF ODOR NUISANCE

The frequency of plant-specific odour events over a given period of ti me is assumed to be a suitable method to assess the exposure to ambien t odour. The validity of such frequency investigations relies on obtai ning a representative sample which in turn depends on randomized but e qually distributed observations over the time period. This presupposit ion is met in the case of non-resident observers by field inspection. Residents can also be chosen for this task. They make odour observatio ns with the help of an electronic diary which calls a person at random ly chosen moments. There is a correlation with the extent of nuisance determined by public survey. However, the results show as well that eq ual odour frequencies may evoke different nuisance levels in the popul ation, with the type of plant and its hedonic odour tone of emission p laying an important role.