What Is MARPOL Annex VI? A Guide to Air Pollution from Ships

Important compliance documents include the:

• Bunker Delivery Note (BDN); and
• Required fuel oil samples.

These provide evidence that fuel supplied and used onboard complies with Annex VI requirements.

Ozone-Depleting Substances

Regulation 12 controls ozone-depleting substances associated with equipment such as refrigeration and air-conditioning systems.

Deliberate emissions are generally prohibited, and applicable ships must maintain the required records concerning ODS servicing, discharge and disposal.

Shipboard Incineration

Regulation 16 controls shipboard incineration.

Certain materials are prohibited from being incinerated onboard, and approved incinerators must be operated according to the manufacturer's instructions by personnel familiar with their correct operation.

Energy Efficiency: EEDI, EEXI, SEEMP and CII

Modern Annex VI goes beyond conventional air pollution.

EEDI establishes technical energy-efficiency requirements primarily for new ships.

EEXI applies technical energy-efficiency requirements to applicable existing ships.

SEEMP provides a framework for managing ship energy efficiency.

CII measures the operational carbon intensity of applicable ships and gives an annual rating from:

A → best performance
B
C
D
E → poorest performance

The mandatory EEXI and CII framework has applied since 2023.

IAPP Certificate and Port State Control

Applicable ships are issued an International Air Pollution Prevention (IAPP) Certificate following the required surveys.

Its validity generally does not exceed five years, subject to the applicable survey and endorsement requirements.

Port State Control may check certificates, fuel documentation, emission-control equipment and whether the crew understands essential Annex VI procedures.

Key Takeaways

For seafarers, the most important Annex VI points to remember are:

NOx → Tier I, II and III

Fuel sulphur → 0.50% globally

SOx ECA fuel sulphur → 0.10%

Marine diesel engines → Regulation 13 generally applies above 130 kW

IAPP Certificate → normally maximum five years

EEDI/EEXI → technical energy efficiency

SEEMP → energy-efficiency management

CII → operational carbon-intensity rating A–E

MARPOL Annex VI has evolved from controlling ship exhaust emissions into a wider framework covering air pollution, energy efficiency and the carbon performance of ships.