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MOVES and Related Models

Emissions Models and Other Methods to Produce Emission Inventories

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An emissions inventory is a summary or forecast of the emissions produced by a group of sources in a given time period. Air pollution emission inventories are the basis for:
  • trends analysis
  • regional and local scale air quality modeling
  • regulatory impact assessments
  • human exposure modeling.

Inventories of air pollution from mobile sources are often produced by emissions models such as the MOtor Vehicle Emission Simulator (MOVES). See the following resources for information and guidance on preparing mobile source inventories.

​On this page:

General Guidance for Preparing Inventories

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Estimating Commercial Marine Emission Inventories and Port Emissions

EPA has developed new marine inventory techniques that are more similar to the techniques we use for mobile sources generally, and rely on emission factors, population estimates, and usage characteristics.

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Estimating Emissions from Locomotives

  • Emission Factors for Locomotives (PDF) (9 pp, 260K, April 2009, EPA420-F-09-025): this fact sheet lists emission factors for locomotives and provides instructions for preparing locomotive emission inventories based on these factors and annual fuel consumption rates.

Estimating Emissions from Aircraft

Emissions from aircraft are usually estimated with a Federal Aviation Administration Model. Additional information on aviation emissions is available at the EPA Aviation website.

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