MARPOL

Definition

MARPOL, the International Convention for the Prevention of Pollution from Ships, sets the rules under which ships must avoid polluting the marine environment. Its six annexes cover oil (Annex I), noxious liquid substances in bulk (II), harmful substances in packaged form (III), sewage (IV), garbage (V), and air pollution (VI). Annex VI is where the global sulphur cap (0.5% since 2020) and the EEXI and CII carbon-intensity rules sit. MARPOL is enforced by Port State Control.

How Vessel Hunter uses MARPOL

MARPOL-driven retrofits, such as scrubber installs, ballast water treatment systems, and EEXI engine power limiters, open commercial windows that Vessel Hunter flags to shipyards and service providers ahead of time.

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Related terms

• PSCPort State Control

  Inspections of foreign-flagged vessels in a port’s waters, run under regional MoUs to enforce international maritime conventions.

• SOLASSafety of Life at Sea

  The principal IMO convention on the safety of merchant ships, covering construction, fire protection, life-saving, navigation, and more.

• IMO 2020 Sulphur Cap

  The MARPOL rule capping the sulphur content of marine fuel at 0.5% worldwide since 2020.

• EEXIEnergy Efficiency Existing Ship Index

  An IMO measure of an existing ship’s design energy efficiency, required to meet a CO2 standard since 2023.

• Ballast Water ManagementBWM

  The regime requiring ships to treat ballast water before discharge to stop the spread of invasive species.

The bigger picture

MARPOL is one piece of the commercial maritime picture Vessel Hunter pulls together for shipyards, suppliers, service providers, and port agents. Every vessel record bundles AIS, ownership, inspections, dry-dock history, casualty record, classification status, and a verified contact for the operator decision-maker behind the ship, so the team that reaches out first wins the work.

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