Analysis also reveals that even in sulphur emission control areas (SECAs), where the most stringent marine sulphur fuel standard is mandated, air pollution from cruise ships remains of great concern. In Denmark, for example, whose coasts are entirely within SECAs, cruise ships emitted 18 times more SOX in 2017 than all the country’s 2.5 million passenger vehicles in a year. This is a reflection of both the effectiveness of the fuel quality directive for road transport fuels and the failure to implement equivalent standards for the shipping industry. Ships SO X will still remain considerably large compared to passenger car fleet even after the introduction of the global 2020 marine sulphur cap.