Modeling Tip – April 2013

Complex air dispersion modeling projects may require large amounts of time to process. One way to reduce model runtimes is to reduce the number of receptors. A method by which some regulatory agencies allow modelers to reduce their receptors is through the use of significant receptors. To identify significant receptors, modelers must first complete a run using a large receptor grid. A concentration threshold is specified and receptors which exceed the threshold are extracted for further processing.

The latest release of AERMOD View, Version 8.2, includes a brand-new feature which allows modelers to export a list of receptors by their concentration. To export these receptors, follow the steps below.

Step 1: Perform an AERMOD model run. Be sure to include Contour Plot Files in the Output Pathway options for the averaging period and source group combinations of interest.

Step 2: Following the successful completion of the model, go to the Plots Tree Menu and select the plot file you wish to view.

Step 3: Click the Export to CSV button and select the Export Range option. This will open the Export Plot to CSV Options window.

Step 4: Identify the concentration (or deposition flux) range over which receptors will be exported. In the example below, all receptors with a concentration exceeding 188 µg/m³ will be exported to the CSV file.

Step 5: The exported CSV file can be imported to any AERMOD View project as a series of new discrete receptors. Under the Receptor Pathway, select the Discrete Cartesian option and select Import from File from the Actions menu.

Step 6: The Receptor Import Parameters window will appear with the receptor data divided into columns. The data is ordered in an identical manner to the contour plot file.

• Column 1 contains the X coordinate data


• Column 2 contains the Y coordinate data


• Column 3 has the measured concentration at the exported receptor


• Column 4 contains the elevation


• Column 5 contains the hill height