1 air pollution modeling software

2 flare stacks   

3 odor units  

4 air dispersion models

5 environmental GIS 

6 environmental reports  

7 indoor air quality  

8 environmental health  

9 environmental risk assessment  

10 stack testing  

11 atmospheric pollution  

12 air modeling  

13 gas dispersion  

14 air pollution cars  

15 indoor air pollution  

16 air pollution analysis  

17 air pollution mapping  

18 air pollution  

19 air pollution environment  

20 air pollution dispersion modeling  

21 air monitoring  

22 vehicle emission modeling  

23 air pollutants  

24 air quality modeling software   

25 air emission modeling software

26 indoor air pollution modeling

Odor concentration: 

The measurement of odor concentration is the most widespread method to quantify odors. It is standardized in CEN EN 13725:2003. The method is based on dilution of an odor sample to the odor threshold, at which the odor can just barely be perceived by 50 % of the test panel. The numerical value of the odor concentration is equal to the dilution factor that is necessary to reach the odor threshold. Its unit is the European Odor Unit, OU_E. Therefore, the odor concentration at the odor threshold is 1 OU_E by definition.

To establish the odor concentration, an olfactometer is used which employs a panel of test persons. A diluted odorous mixture and an odor-free gas (as a reference) are presented from sniffing ports to a group of panelists. In comparing the gases emitted from each port, the panelists are asked to report the presence of odor. The gas-diluting ratio is then decreased by a factor of 1.4 or two (i.e. the concentration is increased accordingly). The panelists are asked to repeat their judgment. This continues for a number of dilution levels. The responses of the panelists over a range of dilution settings are used to calculate the concentration of the odor in terms of European Odor Units (OU_E/m³).

The test persons must fulfill certain requirements, for example regarding their sensitivity of odor perception. The main panel calibration gas to verify this requirement used is n-Butanol.

You have the option to consider a null vertical momentum in point sources. This is usefull if you have a landfill (area source with no vertical momentum) small in comparition with the working area. You can treat it as a point source.

Estimate odor.- With this module you can estimate the odor in simple cases. You can introduce the another other odor flux quantity, if you want.

Odor units