Stuttgart has tried with a voluntary Smog Alarm, or 'Feinstaubalarm' when the pollution is very high for the last two years. This year, the information campaign was very coordinated, and people could be easily informed of the Smog Alarms. The Stuttgart Mayor had stated, if the voluntary scheme did not have the required effect this winter, then a mandatory schem would be implemented next winter.
This winter there have been 168 days of Alert. In January and February there have been more Alert days than non alert days. There were 17 alert days in January, 14 days in February (out of the 23 days of February so far).
The Stuttgart Mayor has announced that from next winter there will be a mandatory ban of all pre-Euro 6 / VI diesel vehicles during Smog Alarms. There will be exemptions for delivery and tradesmens vehicles.