NOxpäästöjä

NOxpäästöjä refers to the emissions of nitrogen oxides (NOx), a group of gases that includes nitric oxide (NO) and nitrogen dioxide (NO2). These gases are produced when nitrogen in the air reacts with oxygen at high temperatures, a process that occurs naturally in lightning and in the atmosphere, but is also a by‑product of combustion in engines and industrial processes. In Finland, as in many countries, NOx emissions are monitored closely because they contribute to air pollution, acid rain, and the formation of ground‑level ozone, which has adverse health effects such as respiratory irritation and exacerbation of asthma.

Typical sources of NOx in Finland include road transport, especially gasoline and diesel vehicles; heavy‑duty trucks; and heating systems that burn fossil fuels such as coal, oil, or natural gas. Industrial activities such as power generation, metal smelting, and chemical manufacturing also emit significant amounts of NOx. In recent decades, the Finnish government has implemented a range of policies to reduce these emissions, including the adoption of Euro emission standards for vehicles, the promotion of low‑emission public transport, and the introduction of the "green tax" on fossil fuels. The European Union’s Air Quality Directive and its subsequent revisions set binding limits for NOx concentrations in both ambient air and specific point sources, encouraging member states to adopt stricter national regulations.

Technological measures to curb NOx include selective catalytic reduction (SCR) systems in diesel engines, exhaust gas recirculation (EGR) in gasoline engines, and improved burner designs in industrial furnaces. Renewable energy alternatives, such as wind and solar, also reduce the need for fossil‑fuel‑based power generation, thereby cutting associated NOx emissions. Monitoring and reporting are managed by agencies such as the Finnish Environment Institute, which provides data on emission trends and air pollutant concentrations to support evidence‑based policymaking.