Roll back to a standard

I wish to assess the health impact of all anthropogenic pm2.5, and have reason to believe that the background non anthropogenic level is 2.5ug/m3 (annual average). I assume I can do this by using the ‘‘roll back to a standard’’ function.
I set the standard to 2.5 , but the resulting AQGX has a range of low values across the geographic units, ranging from 0.1 to 2.12. I was trying to set them all to 2.5. Why am I getting this result?
Is there a simpler way to set a uniform Controlled level?
Ben Ewald

Hi Ben,

A slightly easier way to do this is to:

  1. Create a baseline air quality grid using recent PM2.5 concentrations
  2. Create a control air quality grid, where each grid value is set to 2.5 ug/m3

Run BenMAP-CE using the above two grids, and the program will generate the health impacts attributable to the difference between the two grids.

Hope this helps!


Hi Neal
That is what I want to do, but I cant work out how to make an air quality surface where every value is 2.5. Can we directly edit these? Could you send some instructions?
An AQGX file doesnt open in Excel. How would I directly edit it?
I can see the tool for exporting an AQGX but not the tool to then import it after editing.


Are you familiar with the procedure for creating an air quality grid from a .csv or .xlsx file? If you don’t already an air quality input dataset saved as either .csv or .xlsx, then you can create a .csv air quality input file from an existing .aqgx file using the air quality grid export feature:

  1. Navigate to tools–>export air quality surface
  2. Select the air quality grid you’d like to export
  3. Save the file as a .csv
  4. Open the file in Excel and edit the file

Let me know if this helps!

Thanks Neal. I figured that one out- export an existing grid, edit in Excel, and import it as if it were the output of an air model. It was this last step that was not apparent from the instruction manual.