The 84th session of the MEPC concluded with a revitalized commitment to the IMO Net-Zero Framework, establishing a rigorous intersessional timeline to finalize global shipping emission measures by late 2026. Key outcomes included the adoption of a new North-East Atlantic Emission Control Area, stricter strategies for marine plastic litter, and a formal resolution addressing environmental risks in the Strait of Hormuz. Beyond decarbonization, the Committee advanced mandatory codes for plastic pellet transport and legally binding biofouling controls, signaling a comprehensive shift toward high-standard maritime environmental governance.
London | May 1, 2026 – The 84th session of the Marine Environment Protection Committee (MEPC 84) concluded at the International Maritime Organization (IMO) headquarters this week, marking what officials described as a vital “restoration of rhythm” for the maritime industry’s decarbonization journey.
Held from April 27 to May 1, 2026, and chaired by Dr. Harry Conway of Liberia, the session served as a high-stakes diplomatic arena where nearly 100 delegations grappled with the future of ship emissions, regional security, and the rising tide of plastic pollution.
The overarching sentiment was one of cautious optimism. IMO Secretary-General Arsenio Dominguez, in his closing remarks, declared the committee was “back on track,” while emphasizing that the path forward requires a fragile commodity: trust.
“We are back on track, but we have to rebuild trust. I encourage you to maintain this momentum through your intersessional work and to prepare submissions that can bring the membership together.”
Table of Contents
1 – The Net-Zero Framework: A Sprint to MEPC 85
The centerpiece of the session was the continued negotiation of the IMO Net-Zero Framework. This suite of “mid-term measures” encompasses both technical and economic mechanisms, specifically a global fuel standard and a GHG pricing mechanism (such as a carbon levy), designed to bridge the price gap between fossil fuels and green alternatives to reach the IMO’s 2050 targets.
Convergence and Conflict
With nearly 100 delegations taking the floor, the debate highlighted a vast spectrum of proposals on a global maritime fuel standard and a GHG pricing mechanism, measures with massive implications for shipowners and fuel suppliers. To navigate this complex web of proposals and reconcile divergent views, the Committee:
- Established an Intersessional Working Group: Tasked with working through the summer and autumn to reconcile divergent views on draft amendments to MARPOL Annex VI, this body will resolve technical concerns and drive convergence ahead of MEPC 85.
- Scheduled Deep-Dive Workshops: The “Chain of Custody” Focus: A specialized one-day expert workshop will be convened to study models for tracking fuel origin and movement. This is critical for ensuring that alternative fuels, from green ammonia to methanol, are properly verified and their emissions accurately traced.
The Road to December
The timeline for the remainder of 2026 is now aggressively set:
- September 1–4: First Intersessional Meeting.
- November 23–27: Second Intersessional Meeting.
- November 30 – December 3: MEPC 85 convenes.
- December 4: A Second Extraordinary Session of the MEPC is scheduled to resume to potentially finalize the regulatory architecture, provided enough progress is made at MEPC 85.
2 – Crisis in the Strait of Hormuz
Beyond emissions, the Committee addressed immediate geopolitical and environmental threats. A formal resolution was adopted condemning attacks on commercial shipping in the Strait of Hormuz.
The Committee warned of the “extreme vulnerability” of the Persian Gulf, noting that attacks involving missiles and drones pose a catastrophic risk of large-scale pollution from:
- Crude oil and refined products.
- Hazardous and Noxious Substances (HNS).
- Chemical residues resulting from fires and explosions.
Secretary-General Dominguez has been tasked with monitoring these environmental impacts and reporting directly to the next IMO Council session.
3 – The North-East Atlantic Emission Control Area (ECA): A New Clean Air Mandate
In a landmark decision for regional health and air quality, the Committee officially adopted the North-East Atlantic Emission Control Area (ECA). This new designation represents one of the most significant expansions of emission oversight in recent years, covering the exclusive economic zones and territorial seas.
- Geography: The ECA spans the Exclusive Economic Zones (EEZs) and territorial seas of Greenland, Iceland, the Faroes, Ireland, the UK, France, Spain, and Portugal, extending 200 nautical miles from their baselines.
- The Rules: Ships operating in this zone must use fuel with a maximum sulphur content of 0.10% (down from the global 0.50% cap).
- Timeline: The regulation enters into force on September 1, 2027, with full compliance becoming mandatory 12 months later in 2028.
- The Health and Environmental Mandate – Impact: By strictly curbing SOx, NOx, and Particulate Matter (PM) within this corridor, the measure aims to drastically reduce the incidence of lung cancer, strokes, and childhood asthma in coastal populations. Beyond the profound human health implications, the IMO emphasized that these reductions will simultaneously mitigate sea acidification and protect European forests and crops from the damaging effects of air-borne pollutants.
4 – Combatting Marine Plastic and the “Pellet Code”
The IMO reaffirmed its goal of zero plastic waste discharges from ships by 2030 through the adoption of the 2026 Strategy and Action Plan on Marine Plastic Litter. This plan supersedes previous 2021 and 2025 frameworks, focusing on:
- Improved port reception facilities.
- Strengthened regulatory compliance.
- Targeted technical assistance for developing states.
Furthermore, the Committee greenlit the development of a mandatory code for the maritime transport of plastic pellets. In response to several high-profile spill disasters, the Sub-Committee on Pollution Prevention and Response (PPR 14) will now draft specific rules for transporting these pellets in freight containers under MARPOL Annex III and/or SOLAS.
5. Ballast Water and Aquatic Biodiversity
After an “experience-building phase” (EBP), the Committee approved a comprehensive package of amendments to the Ballast Water Management (BWM) Convention.
Key updates include:
- Refined implementation guidelines (G4) for Ballast Water Management Plans.
- Closing regulatory gaps discovered during the initial years of the treaty’s enforcement.
- Fishing Gear: A new circular was approved to promote the marking of fishing gear, aligning with FAO voluntary guidelines to prevent “ghost fishing.”
6. Noise Pollution and Future Outputs
The Committee acknowledged the growing concern over Underwater Radiated Noise (URN) from commercial shipping, which disrupts marine life.
- The EBP for noise reduction has been extended by two years to the end of 2028.
- An IMO study on URN emissions has been commissioned to build an evidence base for future mandatory measures.
New Work Streams for 2026-2027
The Committee officially added several items to its agenda:
- Ozone-Depleting Substances: Amending MARPOL Annex VI to prohibit the reintroduction of these substances on ships.
- MASS: Developing measures to address Maritime Autonomous Surface Ships within the MEPC’s purview.
- BBNJ Agreement: A principle agreement to support the “Biodiversity Beyond National Jurisdiction” treaty within the IMO’s framework.
7. Technical Milestones and Biofouling
The session concluded with several technical approvals vital for bunker suppliers and engine manufacturers:
- Fifth IMO GHG Study: Terms of Reference were approved, and the procurement process for the study—which will provide the data used for the next decade of regulation—has begun.
- Methane & Nitrous Oxide: New 2026 guidelines were adopted for measuring $CH_4$ and $N_2O$ emissions on test beds and onboard.
- Biofouling: In a significant move, the Committee agreed that a standalone, legally binding instrument should be developed to manage ship biofouling, moving beyond the current voluntary guidelines to prevent the spread of invasive species.
As the delegates depart London, the industry now looks toward a frantic intersessional period. The message from MEPC 84 is clear: the era of voluntary transitions is ending, and the “Net-Zero Framework” is finally taking concrete shape.
Industry Reaction: A “Historic Win” with Lingering Gaps
While the official adoption of the Atlantic ECA was celebrated at IMO headquarters, the environmental community’s reaction was a mix of triumph and a call for more aggressive action.
A Milestone for Climate and Health
Sönke Diesener, a shipping expert at NABU, hailed the decision as a “historic day,” noting that the benefits extend beyond air quality. “Besides cleaning up the air, ECAs also have a remarkable benefit for the climate: high-quality fuels reduce ground-level ozone formation and drive energy efficiency,” Diesener stated, adding that higher costs for “dirty fossil operations” will ultimately foster the uptake of decarbonization technologies.
The Arctic and the “Soot” Factor
The impact on the fragile Arctic environment was a central theme. Dr. Kåre Press-Kristensen, senior advisor at Green Global Future, emphasized the “co-benefit” of reducing Black Carbon (soot). “Soot is the key reason the Arctic is warming four times faster than the rest of the world,” Press-Kristensen warned, explaining that soot deposits darken ice and accelerate melting.
Expanding the Network
Carolina Silva, shipping policy officer at ZERO, noted that while the new ECA connects existing zones in the North Sea, Baltic, and Mediterranean, “regulatory holes” remain. Silva urged the future inclusion of Madeira, the Azores, and the Canary Islands to ensure both an “economic level playing field” and total protection for coastal communities.
The Scrubber Controversy & Geopolitical Tension
Perhaps most critical for fuel suppliers and technical managers is the ongoing debate over “regulatory blind spots” within the new ECA.
The Scrubber Ban Debate
Dr. Liudmila Osipova, technical lead of the impact assessment report submitted to the IMO, argued that the ECA’s full potential is hindered by the continued use of scrubbers. “Our research shows that banning scrubbers could reduce black carbon emissions by over 30% in the Atlantic ECA and prevent at least 300 premature deaths by 2050,” Osipova stated.
The “Russia” Variable
Dr. Sian Prior, Lead Advisor to the Clean Arctic Alliance, expressed frustration over geopolitical pushback. She noted that Russia, whose waters are not even within the ECA boundaries, indicated it would not follow the requirements. “It is now imperative that this new ECA must be complemented by an IMO regulation aimed at directly limiting emissions of black carbon,” Prior concluded, calling for a “polar fuel regulation” that applies to the wider Arctic.
Bunkering Market Outlook
For the marine fuel industry, MEPC 84 serves as a definitive signal: demand for 0.10% Low Sulphur Distillates will surge across the North-East Atlantic corridor by late 2027. Furthermore, the upcoming “Chain of Custody” workshops indicate that the IMO is moving toward a future where fuel is sold not just by its energy density, but by its verified carbon intensity.
As the industry prepares for a flurry of intersessional work through the autumn, the message from London is clear: the era of voluntary decarbonization is ending, and the era of mandatory, verified global standards has arrived.
Source: IMO | Clean Arctic Alliance