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Project at a Glance

Project Status: complete

Title: Heavy-duty truck evaporative emissions testing for emissions inventory.

Principal Investigator / Author(s): McClement, Dennis

Contractor: Automotive Testing Laboratories

Contract Number: 98-303

Research Program Area: Emissions Monitoring & Control

Topic Areas: Mobile Sources & Fuels


Emission Factor Models are created to permit comparison of alternative strategies for reducing and maintaining ambient pollution levels. New vehicle certification testing methods were developed for light-duty cars and trucks in the 1990's. The new methods provide superior estimates of in-use evaporative emissions than those previously obtained. Little data using the new methods is available for in-use heavy duty trucks. The purpose of this study was to measure evaporative emissions with a limited sample of the larger vehicles using the new vehicle certification protocols. The results will be used to confirm or improve corresponding Emission Factor Model inputs for this class of vehicle. Results of the testing were consistent with results obtained from light-duty vehicles when fuel tank size and vehicle age is considered.


For questions regarding this research project, including available data and progress status, contact: Research Division staff at (916) 445-0753

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