The following models are available to assist the CEQA practitioner in calculating impact to air quality.  The following links will take you directly to these models located on other websites.

• Transportation and Land Use Programs Computer Model (URBEMIS 2007 v.9.2.4)
  The latest URBEMIS 2007 model (version 9.2.4, February 2008) estimates air pollution emissions from a wide variety of land use projects.

(NOTE: An error has been identified associated with the fugitive dust construction mitigation measures for PM.  Therefore, the only mitigation measures acceptable for use are either watering OR chemical suppressants.)

• California Line Source Dispersion Model (CALINE-4)
  CALINE-4 is a dispersion model for predicting air pollutant levels near highways and arterial streets.

• Industrial Source Complex Short Term (ISCST3) Model
  ISCST3 is widely used to assess pollution concentration on receptors from a wide variety of sources, commonly from industrial sources, and was designed to support the EPA's regulatory modeling options.

• Roadway Construction Emissions Model (version 5.1)
  Roadway construction emissions model, developed by the Sacramento Metropolitan AQMD, can be used to assist roadway project proponents with determining the emission impacts of their projects (listed under "Mitigating Air Quality Impacts" heading).

• Hotspots Analysis and Reporting Program (HARP)
  HARP is is a computer software tool that that combines emission inventory database, facility prioritization calculation, air dispersion modeling, and risk assessment analysis to assist with the programmatic requirements of the Air Toxics "Hot Spots" Program.

• Environmental Protection Agency (EPA)'s Air Quality Models

• California Air Resources Board (CARB)'s Air Quality Models