Bunker oil is an orthogonal issue. Generally, it's restricted to offshore use. For example, ships have to switch to low sulphur 60 miles outside of San Francisc

Bunker oil is an orthogonal issue. Generally, it's restricted to offshore use. For example, ships have to switch to low sulphur 60 miles outside of San Francisco Bay. As for the IMO 2020 restrictions, I've read that they have significantly lowered pollution but that would be in addition to Slow Steaming.