Answer
MARPOL Annex VI regulates air pollution, greenhouse gas emissions, and energy efficiency across international shipping. The Annex is structured into five core chapters containing 28 regulations.
Core Statutory RegulationsChapter 1: General
Reg 1–4: General application, exemptions, exceptions, and equivalent compliance methods (e.g., Exhaust Gas Cleaning Systems / Scrubbers under Regulation 4).
Chapter 2: Surveys, Certification, and Means of Control
Reg 5–11: Mandates statutory surveys and certification for ships of 400 GT and above:
IAPP Certificate (International Air Pollution Prevention).
IEE Certificate (International Energy Efficiency).
Port State Control (PSC) inspection protocols and detentions.
Chapter 3: Requirements for Control of Emissions from Ships
Reg 12 (Ozone Depleting Substances): Prohibits deliberate emissions of ODS (e.g., Halon, CFCs, HCFCs). Requires maintenance of an ODS Record Book.
Reg 13 (Nitrogen Oxides - NOx): Applies to marine diesel engines >130 kW. Implements progressive Tier limits based on ship construction date:
Tier I: Ships built 2000–2010.
Tier II: Ships built 2011–2015.
Tier III: Ships built 2016 onward operating inside NOx Emission Control Areas (NOx ECAs), requiring SCR or EGR systems.
Reg 14 (Sulfur Oxides - SOx and Particulate Matter): Sets maximum fuel sulfur content:
Global Cap: 0.50% m/m (effective Jan 1, 2020).
ECA Limit: 0.10% m/m inside designated SOx ECAs (Baltic Sea, North Sea, North American, US Caribbean, and Mediterranean Sea ECAs).
Reg 15 (Volatile Organic Compounds - VOCs): Regulates tank vapor emission control systems (VECS) during cargo transfer on tankers.
Reg 16 (Shipboard Incineration): Regulates thermal destruction of waste; prohibits incineration of PCB, PVC, garbage containing heavy metals, and refined petroleum products contaminated with halogen compounds.
Reg 17 (Reception Facilities): Requires ports to provide adequate facilities for ODS residues and scrubber sludge.
Reg 18 (Fuel Oil Availability and Quality): Governs Bunker Delivery Notes (BDN), representative fuel sampling (MARPOL sample), and Fuel Oil Non-Availability Reports (FONAR).
Chapter 4: Energy Efficiency for Ships (Decarbonization Framework)
| 19 | Application |
| 20 | Goal |
| 21 | Functional requirements |
| 22 | Attained EEDI |
| 23 | Attained EEXI |
| 24 | Required EEDI |
| 25 | Required EEXI |
| 26 | SEEMP: Parts I, II, and III operational management protocols. |
| 27 | Collection and reporting of ship fuel-oil consumption data – IMO DCS:Mandatory fuel oil consumption data collection for ships ≥5,000 GT. |
| 28 | Operational Carbon Intensity – CII: Operational rating system (A through E) measured annually against target reduction factors (Z-factors). |
Chapter 5: Verification of Compliance with the Provisions of This Annex
It provides the statutory framework for the IMO Member State Audit Scheme (IMSAS) regarding air pollution prevention and GHG reduction requirements.
Regulation 29 — Application: States that Chapter 5 applies to all Contracting Parties to the MARPOL Annex VI Protocol.
Regulation 30 — Verification of Compliance: Mandates that every Administration (Flag State) is subject to periodic audits by the IMO to verify that it is effectively giving full effect to the provisions, surveys, and certifications governed by Annex VI.
Regulation 31 — Audit Process: Establishes the operational framework for IMSAS:
Audits are conducted in accordance with the IMO Instruments Implementation Code (III Code) (Resolution A.1070(28)).
Requires Flag States to address and rectify any non-conformities or observations raised during the audit process.