IMPROVING TRANSPORTATION DATA FOR MOBILE SOURCE EMISSION ESTIMATES

This report provides an overview of federal statutes and policies which form the foundation for air quality planning related to transportation systems development. It also provides a detailed presentation regarding the use of federally mandated air quality models in estimating mobile source emissions resulting from transportation development and operations. The authors suggest ways in which current practice and analysis tools can be improved to increase the accuracy of their results. They also suggest some priorities for additional related research. Planning practitioners and policy analysts should find the report helpful in integrating transportation data into air quality analyses. State, metropolitan, and local transportation planners should find the material useful in improving their understanding of and in avoiding potential analytical difficulties associated with assessing project or plan conformity. Finally, the report should assist federal agency practitioners in their efforts to improve analytical methods and tools for determining conformity. The report will also serve as a basic educational resource for current and future transportation and air quality modeling.