Transport contributes significantly to emissions of air pollutants such as CO, NOX, NMVOCs, PM10, PM2.5 and SOX. Such emissions can be grouped into acidifying substances, particulates and ozone precursors. NOX contributes to acidification, formation of ground level ozone and particulate formation.
- PM2.5: particulate matter with aerodynamic diameter of 2.5 μm or less;
- PM10: particulate matter with aerodynamic diameter of 10 μm or less;
- NMVOCs: non-methane volatile organic compounds;
- SOX: sulphur oxides;
- NOX: nitrogen oxides;
- CO: carbon monoxide.