ECA & Special Area checker

Enter a position (decimal degrees or degrees/minutes) to instantly check which MARPOL Emission Control Areas (ECAs) and Special Areas apply. The tool covers:

SOx ECAs (Annex VI, Reg 14) — Baltic Sea, North Sea, Mediterranean Sea (from 1 May 2025): max 0.10% sulphur in fuel at sea.
SOx + NOx ECAs (Annex VI, Reg 13 & 14) — North American ECA (Atlantic, Pacific, Gulf/Alaska), US Caribbean ECA: also Tier III NOx limits for new engines.
Annex I Special Areas — stricter oil discharge limits (Baltic, Mediterranean, Black Sea, Red Sea, Gulfs, Antarctic).
Annex V Special Areas — stricter garbage discharge limits (same areas plus North Sea).

Bounding-box approximation. Consult official MARPOL charts and the ship's SMS for precise boundaries before any discharge decision.

Latitude (decimal ° or DMS)Longitude (decimal ° or DMS)

Bounding-box approximation only. Consult official MARPOL Special Area / ECA charts for precise boundaries. Mediterranean SOx ECA entered into force 1 May 2025 (0.10% sulphur limit at sea, 0.10% in port).

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When to use this tool

Before deciding to change over to compliant low-sulphur fuel (typically the ~1-2 hour switchover from HFO to MGO or VLSFO on ECA entry), before opening a fuel-oil sludge tank valve for discharge, or when planning bunker consumption for a passage that crosses an ECA. Also for post-voyage review of AIS-track compliance.

Worked example

Scenario: Panamax bulker inbound to Long Beach, tracking 245°/13 kn from 32°30'N, 125°00'W. Master needs to know the ECA boundary + timing to complete fuel change-over.

Check position: Enter current lat/lon → returns Within North American ECA (SOx + NOx). Passenger already in-ECA — must be on compliant fuel (0.10% S) + engine on Tier III NOx mode if fitted (post-2016 keel-laid engines).

Interpretation: Confirm switchover is complete + logged in Oil Record Book Part I (fuel change-over is Code J).

Regulatory basis

MARPOL Annex VI Regulation 14 (SOx + PM ECAs), Regulation 13 (NOx ECAs). Boundaries defined by lat/lon corners in MEPC resolutions (recent: MEPC.361(79) adopted Mediterranean SOx ECA effective 1 May 2025). Bounding-box approximation used here for speed; consult official MARPOL charts + the ship's SMS for precise boundaries before any discharge or bunker-change decision.

ECA & Special Area checker

When to use this tool

Worked example

Regulatory basis

See also