Inspections
Inspections for documenting odours
Inspections
Noses are measuring equipment too. If odours cannot be measured at source because the sources are too many or too diffuse, or if calculations need to be checked, there is the possibility of obtaining information about odour pollution in the surroundings by means of inspection. Test persons conduct these types of inspections for us in accordance with the methods described in the relevant standards. The individual odour sensitivey of the test persons is tested regularly using an odour threshhold test.
We make a distinction between plume and grid surveys.
Because the range of an odour, i.e. the length of its plume, depends heavily on meteorological boundary conditions, weather data are recorded during the survey.
The meteorological data are also needed to compare conditions prevailing during grid surveys with long-term weather data recorded by meteorological services to determine the degree of standardization.
Procedure during plume surveys
This method is used to determine the size of the odour plume at a facility in a single weather situation in order to determine the source's intensity. For this purpose, the odour plume is demarcated by walking about the premises: The test persons record the frequency of their odour perceptions at various distances on the facility's leeward side, i.e. downwind side. These frequencies are used to determine the plume's range. If a frequency exceeds a certain value, the point at which the frequency was measured lies within the plume's range.
Once the odour plume's range has been determined in this manner, the measured situation is reproduced on a computer by means of a forecasting model, and the source intensity varied until the forecast and measured parameters coincide.
The advantage of plume surveys is that they always cover the entire facility, the test persons being able to inspect it from the residents' standpoint.
Procedure during grid surveys
If various odour-emitting facilities are situated in a particular region, grid surveys can be used to examine contamination by odours over defined areas. The information yielded by such surveys can be used, for instance, as part of basic urban development and infrastructure planning.
The individual measurement points of a grid survey are inspected by the test persons according to a precisely defined plan. The odours occurring at each of these points are documented over a defined time period. Not considered here are ordinary odours bearing no relation to any facility and originating, e.g. from motor vehicle traffic, household heating installations, sewage systems, vegetation etc.
In this case, too, the test persons put themselves in the resident's position. Sample measurements are conducted at various times of day and night, also during periods of zero emissions from neighbouring facilities.
What sets us apart?
- We are a recognized measurement centre in accordance with Sections 26 and 28 of the Federal Emissions Protection Act (BImSchG) and have been active for about 30 years in the field of odour investigation.
- We have a quality management system. It is certified according to DIN EN ISO 9001:2000 and DIN EN 17025.
- We work with national standard committees for quality assurance and development of odour measurements and projections (VDI 3782, Bl. 13 "ensuring the quality of pollution forecasts", VDI 3884, German elaboration of DIN EN 13725, VDI 3880, "olfactometric sampling")).
- We engage officially certified and attested experts for odour analysis.
- We develop all devices for olfactometric sampling in-house (including long-term samplers, sampling hoods and gas-jet pumps for dynamic pre-dilution).
- The following publications can be found under these links:
- Biofilter
- Biomass, biogas
- Against odours
Which services do we offer?
- We advise you on selecting the odour analysis technique suitable for your requirements Odour measurement at source including computation of propagation, plume survey, grid survey.
- Our test persons conduct plume surveys on location to increase forecast reliability.
- We conduct grid surveys over limited areas as part of town planning, and over large areas surrounding facilities. Wherever necessary, we seek out, test and train persons suitable for the survey.
- We record local wind data, providing wind measurement masts and devices for this purpose.
According to which statutory regulations do we work?
There is such a broad range of tasks in odour assessments that the solutions cannot be standardised. The procedure in such investigations is governed by the Federal Emissions Protection Act (BImSchG), the states' odour pollution directives (GIRL), and national and European standards (DIN EN 13725 (olfactometry), VDI 3940 (inspections)) and other specific standards (e.g. VDI manual on air cleanliness).
Contact:
Our experts are happy to answer your individual questions at any time. Just send us an e-mail by clicking on the contact box (top right).
