ECA (Emission Control Area)
Abbreviation: ECA
MARPOL Annex VI designated sea area with stricter sulphur + NOx limits than the global cap.
Quick facts
- Global sulphur cap
- 0.50% (2020)
- ECA sulphur
- 0.10%
In practice
Master + Chief Engineer switch to compliant fuel on entering ECA + log the switch in the Oil Record Book. Non-compliance triggers PSC detention + potential prosecution in some ECAs.
Regulatory detail & full definition
ECAs are sea areas designated under MARPOL Annex VI where stricter air-pollution limits apply than the global cap. SECA (Sulphur ECA) sets 0.10% max fuel sulphur inside the ECA (vs 0.50% global). NECA (NOx ECA) sets Tier III NOx limits for engines on ships built 2016 or later inside the ECA. Current SECAs + NECAs: Baltic Sea, North Sea, North American, US Caribbean. Mediterranean SECA in force May 2025.
Authoritative source: IMO — Air Pollution + ECA ↗
Related
Source: MARPOL Annex VI
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