This guideline was developed to describe an olfactometric method to investigate odorant samples whose concentrations are above the odour threshold (suprathreshold) and relate them to sensation intensity induced in human. While evaluating many samples whose concentrations vary and exceed odour threshold, intensity variation can be assess. The use of olfactometers and this method allow the evaluation of degree of odorant concentration reduction that could be obtained from different emission treatments or from dilution (such as samplings taken at different distances from the source). Information is given on the procedures that have to be done to realize the tests (sampling procedures from VDI3881, panel selection of at least 8 persons, olfactometer, presentation of the different odorant concentrations, exposure and response to stimuli associated with an intensity level scale from 0 – not perceptible to 6 – extremely strong). The evaluation of the results is also explained with the presentation of the test results, the mathematical evaluation and the graphical presentation to clearly represent the intensity variations of a specific odorant gases or air mixes at their different concentrations. A relationship is established between the odorant concentration and the odour intensity thus giving the suprathreshold intensity variation. However to establish nuisance, the hedonic odour response, the frequency and exposure time have also to be considered.

This guideline is interesting and give the frame for odour intensity determination. However, the information given is general and the results obtained could be difficult to reproduce (different laboratory with different apparatus).