USDA-ARS
15
Freeware
It estimates ammonia, hydrogen sulfide, and greenhouse gas (GHG) emissions.
United States Environmental Protection Agency
14
Freeware
Calculate emission for both on-road motor vehicles and nonroad equipment.
ENVIRON International Corporation
1
Freeware
CalEEMod is a statewide land use emissions computer model.
Hbefa.net
26
Commercial
HBEFA provides emission factors for all current vehicle categories.
