I am looking at the PortStMaarten webcam right now. There are 4 ships in. I know that they have to keep their diesel engines running for power (this has been discussed here previously). Generally you do not see much smoke but the one smaller ship, Silver Wind, seems to be spewing a large amount of black smoke into the air The larger ships don't seem to be visible from their smoke stacks, better scrubbers perhaps.
Are there no industry standards for this?

David K