ECA
Emission Control Area
Meaning
An emission control area (ECA) is a sea area where ships must burn fuel with no more than 0.10% sulphur, or use a scrubber, under MARPOL Annex VI.
Also written as SECA, Sulphur emission control area
ECA explained
ECAs cover the Baltic Sea, the North Sea and English Channel, the North American coasts, the US Caribbean and, since May 2025, the Mediterranean, with more adopted for future years. Some also limit nitrogen oxides from newer engines.
Inside an ECA a ship without a scrubber has to switch to more expensive 0.10% fuel, usually marine gasoil, so the ECA miles on a route feed straight into the voyage's bunker cost.
Example
Of a Ras Tanura–Rotterdam voyage via Suez, roughly 2,400 nautical miles fall inside the Mediterranean and North Sea ECAs.
Related terms
IMO 2020
IMO 2020 is the global limit, in force since 1 January 2020, of 0.50% sulphur in ship fuel outside emission control areas.
Scrubber
A scrubber (exhaust gas cleaning system) removes sulphur from a ship's exhaust, letting it burn cheaper high sulphur fuel oil while staying compliant.
Bunkers
Bunkers are a ship's fuel, mainly very low sulphur fuel oil (VLSFO), high sulphur fuel oil (HSFO) for scrubber-fitted ships, and marine gasoil (MGO).
MARPOL
MARPOL is the IMO's International Convention for the Prevention of Pollution from Ships, covering oil, chemicals, sewage, garbage and air emissions.