The UK cities of Birmingham and Leeds are expected to have Low Emission Zones by 1st January 2020. These are called Clean Air Zones (CAZ), and are low emission zones combined with a toll for vehicles not meeting the emissions standards.
As well a number of cities having Low Emission Zones, and Emergency Schemes, many Regions and in France also
have emergency smog schemes.
There are a number of legal cases running in Germany about air quality. So far two of them have been completed.
These are often reported as 'diesel bans'.
Stuttgart plans to tighten the Low Emission Zone to Euro 5 on the first of January 2019.