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Support Center for Regulatory Atmospheric Modeling (SCRAM)

Photochemical Modeling Tools


The Air Quality Modeling Group has been working over the last several years on a replacement for MATS. The new software is called SMAT-CE (Software for the Modeled Attainment Test - Community Edition) and is being formally released as a replacement for MATS.

SMAT-CE replicates the same tests that are performed by MATS, with identical (or nearly identical) results. SMAT performs the ozone and PM2.5 attainment tests and calculates changes in future year visibility at Class I areas. Detailed information on the recommended attainment tests can be found in EPA's photochemical modeling guidance, Modeling Guidance for Demonstrating Attainment of Air Quality Goals for Ozone, PM2.5, and Regional Haze (PDF)(205 pp, 2 MB, 11-29-2018, 454-R-18-009).


  • SMAT-CE version 1.6 has been updated with PM2.5, regional haze, and ozone ambient data through 2017.
  • For the annual and daily PM2.5 tests, the default “blank mass” values for PM2.5 have been reduced from 0.5 ug/m3 to 0.2 ug/m3, consistent with recommendations in the photochemical modeling guidance.


  • SMAT-CE v1.6 Installer Package (EXE) (1.4 G, 10/28/2019) 
  • Installation instructions
    • Download and open the installer package. The SMAT executable and supporting files will be installed to: C:\Program Files (x86)\SMAT-CE . Once you run the SMAT executable, you will be able to choose between “Annual PM analysis”, “Daily PM Analysis”, “Ozone analysis”, and “Visibility Analysis”.
    • The GUI will look familiar to MATS users. There is also a user’s guide built into the GUI. Note that all SMAT output files will be sent to a different location from the executable and default ambient data files. All configuration files and SMAT generated outputs are sent to the “My SMAT-CE Files” directory under “my documents”. SMAT uses the same data input formats as MATS. All old MATS input files should work directly with SMAT.

SMAT-CE comments and questions should be sent to Brian Timin at