The traffic police and Sofia Municipality carry out mass inspections of cars with diesel fuel. The reason is the highly polluted air in Sofia. Cars without catalysts will be stopped, and their drivers fined BGN 100. During the inspection of cars a special device will be installed to measure harmful emissions and whether they meet the norms. The municipality plans to launch free public transport on days with high pollution. New mobile laboratories are also planned to monitor air quality.
Catalysts are often stolen because of the platinum and precious metals they contain. Attacks on diesel cars are more common due to the higher amount of platinum than in the filters of petrol models.