This is partly outdated. Tight sulphur emission regulations happened in 2015. However they are limited to more populated areas. https://en.wikipedia.org/wiki/S

This is partly outdated. Tight sulphur emission regulations happened in 2015. However they are limited to more populated areas. https://en.wikipedia.org/wiki/Sulphur_Emission_Control_Area https://en.wikipedia.org/wiki/Sulphur_Emission_Control_Area NOx limits are tightening. Didn't get a great link but this has something: http://www.imo.org/en/OurWork/Environment/PollutionPrevention/AirPollution/Pages/Nitrogen-oxides-%28NOx%29-%E2%80%93-Regulation-13.aspx http://www.imo.org/en/OurWork/Environment/PollutionPreventio...