Operational Guide · Registers & Logbooks

# MARPOL Annex VI — Prevention of Air Pollution

The full map of Annex VI: SOx/NOx, ECAs, ODS, VOCs, incineration, fuel quality and energy efficiency (EEXI, CII, DCS) — with the picture updated to 2026.

MARPOL Annex VI SOx NOx ECA EEXI CII IMO DCS Net-Zero Framework

## Operational Explanation

MARPOL Annex VI governs the prevention of air pollution from ships: sulphur oxides (SOx) and fuel quality, nitrogen oxides (NOx), ozone-depleting substances (ODS), volatile organic compounds (VOCs), on-board incineration, and — from Chapter 4 — energy efficiency and greenhouse gas emissions (EEDI, EEXI, SEEMP, CII, IMO DCS).

This topic is the cross-cutting reference that the module's individual operational procedures (Fuel Oil Changeover, Incinerator Operations) point back to: the full regulatory picture is here, the step-by-step practical procedure is there.

Main developments 2025–2027: Mediterranean SECA from 1 May 2025 (Resolution MEPC.361(79)); new BDN/IMO DCS granularity rules from 1 August 2025 (Resolution MEPC.385(81)); SEEMP Part II deadline on 31 December 2025; new Canadian Arctic and Norwegian Sea ECAs from 1 March 2026 (Resolution MEPC.392(82)); the IMO Net-Zero framework approved in principle at MEPC 83 (April 2025), with the October 2025 session postponed to a resumed session in autumn 2026, and entry into force expected 1 March 2027.

## Regulatory Reference

MARPOL Annex VI — main structure: Reg. 1-3 (application), Reg. 2 (definitions), Reg. 5-11 (survey and certification, IAPP/EIAPP), Reg. 12 (ODS), Reg. 13 (NOx, NOx Technical Code 2008), Reg. 14 (SOx and fuel quality, ECAs), Reg. 15 (VOCs), Reg. 16 (incineration), Reg. 18 (fuel quality and Bunker Delivery Note), Chapter 4 (EEDI, EEXI, SEEMP, CII, IMO DCS).

## Scope of Application

Applies to all ships subject to MARPOL, with requirements differentiated by tonnage/type (e.g. EEXI/CII for ships above 5,000 GT; IAPP certification for ships of 400 GT and above on international voyages).

## Procedure / How to Complete It

1. Verify the certificate class required (IAPP for the ship, EIAPP for each diesel engine subject to Reg. 13) and its survey validity/expiry.
2. Check the planned navigation area against active ECAs (North America, US Caribbean, Baltic, North Sea, Mediterranean from 2025, Canadian Arctic and Norwegian Sea from 2026) and arrange compliant fuel/EGCS.
3. Verify the Bunker Delivery Note for every bunkering operation and retain it together with the MARPOL sample for the required period.
4. Update SEEMP Part II (deadline 31 December 2025) and verify that IMO DCS data is aligned with the new granularity required from 1 August 2025.
5. Monitor the evolution of the IMO Net-Zero framework (resumed session in autumn 2026) for medium-term CII/EEXI planning.

## Practical Example

Example pre-departure check: a ship bound from North Africa to Northern Europe through the Mediterranean — since 1 May 2025 the entire route lies within a SECA, so the changeover to 0.10% S fuel (or use of an approved scrubber) must be planned from departure, not only on entering the Baltic/North Sea as in the past.

## Real Cases

Detention/deficiency cases linked to Annex VI typically stem from an expired IAPP certificate not updated after changes to the SOx management plan, from a missing or inconsistent BDN, or from failing to account for a newly designated ECA (such as the Mediterranean) in voyage planning.

## Common Mistakes Mistake Library

Mistake | Consequence | How to avoid it
--- | --- | ---
Voyage planning not updated with the new ECAs (Mediterranean 2025, Arctic/Norway 2026) | Use of non-compliant fuel in an area now regulated as a SECA | Update charts and voyage planning procedures with every new MEPC resolution entering into force
Expired IAPP certificate or missing EIAPP for a modified engine | PSC deficiency, possible detention | Track survey deadlines in a dedicated register and coordinate Annex VI surveys with other statutory surveys
SEEMP Part II not updated or incomplete IMO DCS data against the new required granularity | Non-compliance in data collection and possible knock-on effects on CII rating | Review SEEMP Part II before the 31 December 2025 deadline and align DCS data-collection systems with the new requirements

## PSC Observations

PSC inspectors verify the validity of IAPP/EIAPP, the consistency between BDN, MARPOL samples and the fuel oil log, the crew's awareness of the ECAs currently in force along the route, and the presence/currency of SEEMP Part II.

## Operational Tips

- Keep an always up-to-date table of active ECAs with their entry-into-force dates, for use during voyage planning.
- Coordinate Annex VI certificate deadlines (IAPP/EIAPP) with the ship's general survey calendar.
- Follow regulatory updates (Regulatory Updates section) to avoid being caught unprepared by new MEPC resolutions, including the evolving IMO Net-Zero framework.

## Checklist

- IAPP certificate valid and consistent with the ship's current configuration
- EIAPP certificates present for all engines subject to Reg. 13
- ECAs on the planned route identified and compliant fuel/EGCS arranged
- Bunker Delivery Notes and MARPOL samples correctly filed
- SEEMP Part II updated and IMO DCS data aligned with current requirements

## FAQ

What is the difference between IAPP and EIAPP?
The IAPP (International Air Pollution Prevention Certificate) is the certificate for the ship as a whole; the EIAPP (Engine International Air Pollution Prevention Certificate) is issued for each individual diesel engine subject to the NOx limits of Regulation 13.
Is the Mediterranean already a sulphur ECA?
Yes, since 1 May 2025 (Resolution MEPC.361(79)) the entire Mediterranean Sea is a SECA: 0.10% sulphur m/m limit unless an equivalent scrubber is used.
What does the IMO Net-Zero framework change?
Approved in principle at MEPC 83 (April 2025), the framework would introduce a GHG emissions pricing/standard mechanism; the October 2025 adoption session was postponed to a resumed session in autumn 2026, with entry into force expected from 1 March 2027. Status should be monitored via regulatory updates.
When is the deadline to update SEEMP Part II?
31 December 2025, in line with the evolving CII/IMO DCS data-collection requirements.
🎬 Additional photos, videos and interactive diagrams for this topic will be available in a future version of the platform.

## Related Topics

Fuel Oil Changeover (ECA)Incinerator Operations PSC Knowledge Base (IT)Regulatory Updates (IT)

### Leave feedback

Help us improve the platform during the beta -- it takes thirty seconds.

How useful do you find the platform so far?
Comment (optional)
Sign me up for the newsletter
Role