Sulphur dioxide immissions
Higher concentrations of sulphur dioxide (SO2) can have especially negative effects on the respiratory tract; asthmatics and people with chronic respiratory diseases are particularly at risk. SO2 is also toxic to plant life (phytotoxic). Moreover, it is an important precursor in the formation of acid rain. Sulphur dioxide emissions result from the combustion of sulphur-containing transport and heating/process fuels.


Sulphur dioxide pollution has decreased by more than 95% since the mid-1980s and is now at a low level at all measuring stations (significantly below the immission limit level of 30 μg/m³). This positive development is a direct consequence of corrective measures initiated in the 1990s. Two major reasons behind the reduction achieved in SO2 emissions were the decrease in the sulphur content of heating oil and the changeover to natural gas that came about in response to strict emission limit levels.
- Related indicators
- Sulphur dioxide emissions
The member states of the EU also measure sulphur dioxide immissions and calculate corresponding indicators. Switzerland has lower sulphur dioxide concentrations than its neighbouring countries. (Switzerland has no thermal power plants, relatively little shipping and burns almost no coal or heavy oil).
The current status and development of air pollution throughout Switzerland are measured and recorded by the National Air Pollution Monitoring Network (NABEL), which is jointly operated by the FOEN and EMPA (Swiss Federal Laboratories for Materials Science and Technology). It comprises 16 measurement stations distributed throughout the country, which provide data relating to all the most important pollution situations. For the assessment of sulphur immissions, data are collected from NABEL stations with permanent measurement cycles.
Targeted trend | Initial value | Final value | Variation in % | Observed trend | Assessment |
---|---|---|---|---|---|
Decrease | Average 1991-1993 | Average 2021-2023 | (1) -95.64%, (2) -93.77%, (3) -92.89%, (4) -91.32% | (1) Decrease, (2) Decrease, (3) Decrease, (4) Decrease | positive |
(1) urban, (2) suburban, (3) rural, (4) pre-alpine/Jura range |
Further information