Report, Heavy-Duty Diesel Vehicle Modal Emission Model Pathway: Energy Efficiency, Conservation, and Fuel Switching in Transportation → Heavy-Duty Vehicles and Freight → Inspection and Maintenance Requirements for HDVsJurisdiction: Executive Branch → Individual Agencies EPA’s 2005 report proposed heavy-duty Diesel vehicle modal emission modeling framework (HDDV-MEMF) for heavy-duty diesel-powered trucks and buses.