Scrubber
An exhaust gas cleaning system that removes sulphur oxides from a ship’s emissions, letting her burn cheaper high-sulphur fuel.
A scrubber, or Exhaust Gas Cleaning System (EGCS), washes sulphur oxides out of a ship’s exhaust so the vessel can comply with the sulphur limit while still burning cheaper high-sulphur fuel oil. Open-loop systems discharge the wash water to sea; closed-loop and hybrid systems retain or treat it.
The investment case for a scrubber rests on the price spread between high- and low-sulphur fuel: a wide spread pays back the capital fast. Some ports and states restrict open-loop discharge, which has pushed newer installs toward hybrid designs.
On TheMaritime
Also known as: scrubber, EGCS, exhaust gas cleaning system.
Related terms
Very Low Sulphur Fuel OilVLSFO
Marine fuel with no more than 0.50% sulphur, the compliant fuel for most waters under the IMO 2020 sulphur cap.
Bunkers
The fuel a ship burns — and, by extension, the act of taking on that fuel (bunkering). Usually the single largest voyage cost.
MARPOL
The IMO convention preventing pollution from ships — oil, chemicals, sewage, garbage and air emissions across six annexes.
Plain-English reference definition — our own explanation of a standard shipping concept, not a licensed source or legal advice. See the full glossary or the broader maritime dictionary.
Last reviewed: June 2026.