CEN/TC 264/WG 27 - Measurement of odour impact by field inspection

This part of the European Standard describes the plume method for determining the extent of recognizable odours from a specific source using direct observation in the field by human panel members under specific meteorological conditions.
The plume method involves the determination of the presence or absence (YES/NO) of recognizable odours in and around the plume originating from a specific odorant emission source, for a specific emission situation and under specific meteorological conditions (specific wind direction, wind speed and boundary layer turbulence). The unit of measurement is the presence or absence of recognizable odours at a particular location downwind of a source. The extent of the plume is assessed as the transition of absence to presence of recognizable odour.
The primary application of this standard is to provide a common basis for the determination of the odour plume extent in the member states of the European Union.
The results are typically used to determine a plausible extent of potential exposure to recognizable odours, or to estimate the total emission rate based on the plume extent, using reverse dispersion modelling.
The field of application of this European Standard includes the determination of the extent of the recognizable odour plume downwind from a source, under specific meteorological conditions (e.g. wind direction, wind speed, turbulence, etc. (see 7.3.2).
This European Standard does not include:
-   the measurement of intensity of ambient odours;
-   the measurement of hedonic tone of ambient odours;
-   the measurement of the odour exposure in ambient air over a longer time period in an assessment area;
-   the calculation of estimated source emission rate from plume assessment using reverse dispersion modelling.
An overview of the interaction between existing odour exposure assessment methods is given in Annex A including grid method (Part 1), plume method (Part 2) and olfactometry according EN 13725.

This part of the European Standard describes the grid method for the determination of the level of odour exposure in ambient air. It provides a set of instructions for measurement of ambient odour exposure within a defined assessment area, using qualified human panel members, over a sufficiently long period of time to be representative for the meteorological conditions of that location, and hence determine the distribution of the frequency of exposure to odours within the assessment area. The sources of the odorant under study may be located within or outside the assessment area.
The primary application of this European Standard is to provide a common basis for evaluation of exposure to ambient odours in the member states of the European Union. The field of application of this type of measurement is to characterize the level of odour exposure within the study area, in order to assess whether the impact of that exposure on resident population could be a justified cause for annoyance, using exposure criteria. The unit of measurement of the method is the frequency of odour hours for an assessment square, defined by four measurement points as a representative value for odour exposure for local conditions, e.g. local odour sources and the meteorology of that location.
This European Standard does not include:
-   the measurement of intensity of ambient odours,
-   the measurement of hedonic tone of ambient odours,
-   the calculation of odour exposure in specific weather conditions in order to determine the frequency distribution of recognizable odour in an odorant plume,
-   the calculation of estimated source emission rate from plume assessment using reverse dispersion modelling.
An overview of the interaction between existing odour exposure assessment methods is given in Annex A, including grid method (Part 1), plume method (Part 2) and olfactometry according to EN 13725.