Main Emission Sources
There are many sources of the pollutants contributing to smog. These include:
- The transportation sector (on and off road vehicles and engines) is a significant source of NOx, VOCs, and direct particulate matter emissions
- Electricity Generation and Industry are significant sources of NOx, VOCs, SO2, and direct particulate matter emissions
- Industrial Energy Use is a significant source of NOx, SO2, and direct particulate matter emissions
- Solvent use is a significant source of VOC emissions
- Open sources (paved and unpaved roads, construction, agriculture, etc) are major source of both fine and coarse particulate matter
- Residential Wood Combustion is a significant source of fine particulate matter in winter
Natural or biogenic sources also contribute to smog - forest fires contribute particulate matter, and VOCs, while vegetation contributes VOCs.
