VDI 3882

Overview

VDI 3882 refers to the German standards and methods of olfactometry, which is split into 2 major parts detailed below:

VDI3882 Part 1

Part 1 describes an olfactometric method of investigation. It can be used to assess inhaled samples having odorant concentrations above the odour threshold (suprathreshold concentrations). This is in relation to the sensation intensity they induce in human beings. For a given odourant concentration, this sensation intensity is substantially dependent on the substance and/or mixture. This means that height can be used in variation intensity calculations as a characteristic of that sample. The investigation of the odour intensity of individual concentration levels using an olfactometer makes it possible to assess it under field conditions.

Above all, with the field of emission reduction, the determination of the intensity of an untreated waste provides guide values. These can be used for the reduction in odorant concentration needed to maintain certain odour intensity at the source. In this connection, the assessment will be all the more reliable, the less the untreated gas composition is altered by the reduction technique used.

The relationship between the odour intensity and the odorant concentration makes it possible to use intensity determinations carried out on clean gas samples and dispersion calculations for odorants [6] to make forecasts of the theoretically remaining odour intensi¬ ty in the field (ambient air). Perceptible interfering actions due to synergistic effects with other odorant emissions are not allowed for in this connection since they cannot be included in the calculations.

However, the variation in intensity cannot be used to describe the nuisance potential of an odourant sample.

Odour Guideline Standards

The Standards set by this Guideline apply to odour intensity determinations carried out on the following samples :

a) emission samples obtained from a source of the odour
b) individual substances or specified mixtures of substances in neutral air,
c) Above all, emission samples provided their odorant concentration is high enough for an olfactometer to be used

VDI3882 Part 2

Part 2 of Guideline VDI 3882 describes an olfactometric method of evaluating the hedonic tone of odorous samples. These samples are above-threshold odourant concentrations according to the sensation scale “pleasant – unpleasant”. The hedonic tone of an odour is contingent on the nature or mixture of the odorous substance or substances. These are on the odourant concentration – the perceived intensity of the odour – and on the background experience of the individual. This means that, by evaluating several above-threshold stages of concentration of a specific odorous sample. However, it is possible to plot the hedonic odour tone as a characteristic curve of the sample under investigation.

The hedonic tone of an odour, most importantly, must not be confused with its quality (fragrant, pungent, stale, or smell like…)

In conclusion, with regards to the methods recommended in VDI 3881 for determining odourant concentration (odour threshold) and odour intensity, the additional determination of the hedonic odour tone of an emission sample frequently permits an assessment of its nuisance effect. This occurs under ambient air conditions, though a conclusive assessment of the actual degree of nuisance is not possible with olfactometric methods alone. In cases where it is necessary to ascertain the nuisance effect, additional sociological methods (e.g. neighbourhood surveys) can be helpful

Hedonic Tone Guidelines

This guideline is valid for the determination of the hedonic odour tone of the following types of sample :

a) Above all, emission samples come from a source of the smell
b) Single substances or defined mixtures in a neutral gas,
c) Ambient air samples, with regards to their odorant concentration, is high enough for detection by the olfactometer