Mobile Source Emission Inventory
This page last updated on June 2013
Mobile Source Analysis Branch staff are working on a number of updates to mobile source emissions inventories and assessment tools, including EMFAC2013. We are planning a series of workshops in 2013 to discuss these updates and development of new tools. The first will be on June 5, 2013 in Sacramento. Please click on the link below for more information.
- Includes a new handbook and tools with updated online databases and training that allow easier access to emission factor data and provide tips for project level assessment
- Corrects the number of starts and associated emissions in Santa Clara County in EMFAC2011-LDV and EMFAC2011-SG, which had led to an overestimate of emissions. No other counties were affected and no model algorithms were changed in the update
- Updates technical documentation to reflect these improvements
- All EMFAC users should download the latest version of EMFAC2011-LDV and EMFAC2011-SG
The mobile source emissions inventory is ARB’s tool for assessing the population, activity, and emissions from mobile sources. These inventories are constantly being revised and updated to support the latest air quality plans and regulations. Periodically these inventories are compiled and released to the public for use in transportation and air quality assessments both internal and external to the agency. Mobile source inventories are developed by the Mobile Source Analysis Branch in the Planning and Technical Support Division. In these web pages you will find two different ways of accessing current information. Data can be accessed for specific regulatory items by mobile source category or through the methods and in some cases models that are used estimate emissions.
Individual category-specific emissions estimates and documentation are developed for specific agency regulatory activities. Categories include cars/light truck assessments for emissions standard development, heavy duty truck and in-use off-road emissions estimates for in-use diesel Rules, and category specific emissions estimates for ocean-going vessels, pleasure craft, and many other types of vehicles.
ARB periodically releases multi-category inventories that provide a snapshot of emissions developed periodically for air quality planning purposes. These inventories are developed using methods that are integrated into database tools and models that can be found here. ARB also published emissions output periodically which can be accessed through on-line web tools that can be found here.
Additional information is available for previous model versions, system documentation and archived information.
- Join our MSEI listserv
- For more information on Mobile Source Emissions Inventories, please email us.