Decoded: Seven Battles at MEPC 84 That Will Reshape Shipping Costs

The Regulatory Clock Hasn't Stopped

While the maritime world watches Islamabad and counts trapped vessels at Hormuz, the IMO's regulatory machinery grinds forward. The Marine Environment Protection Committee meets for its 84th session in London from April 27 to May 1 — and the agenda carries at least seven fights that will alter shipping economics for the next decade.

The timing could not be more consequential. Operators managing the Hormuz crisis are about to face a parallel regulatory storm. MEPC 84 isn't just another committee meeting — it's the session where the net-zero framework's survival will be tested, new fuel measurement rules will be locked in, and an entirely new emission control area could be designated.

Here are the seven battles that matter.

Battle 1: The Net-Zero Framework — Dead or Alive?

The headline fight. The IMO Net-Zero Framework was approved 63-16 at MEPC 82 in April 2025, then failed to gain adoption at an extraordinary session in October 2025, where the vote narrowed to 57-49 — with the United States leading opposition. MEPC 84 will resume those discussions with 57 documents submitted under Agenda Item 7.

What changed since October: The US position hardened. A joint statement from the Department of Energy branded the framework a "global carbon tax" and explicitly threatened retaliation against nations supporting it. Meanwhile, 87 maritime firms — including CMA CGM, Maersk, and MSC — issued a joint call urging adoption.

What to watch: MEPC 84 is not expected to adopt the framework. The real question is whether the committee sets a clear path to the reconvened extraordinary session, now scheduled for October 2026. If the US blocks even procedural progress, the framework enters regulatory limbo — and the EU's unilateral ETS becomes the de facto global standard by default.

Who's affected: Every vessel trading internationally. The framework proposes a GHG fuel intensity standard taking effect from 2028 and a maritime GHG pricing mechanism. Tanker operators face the steepest compliance costs; LNG carriers may benefit from methane-slip credit structures.

Battle 2: Methane Measurement — The LNG Fleet's Reckoning

MEPC 84 will consider three sets of draft guidelines: test bed and onboard measurements of CH4 and N2O emissions from marine diesel engines, engine load monitoring (ELM) guidelines, and continuous emission monitoring systems (CEMS) guidelines.

This matters because methane slip — unburned methane escaping from LNG-fueled engines — is the dirty secret of the "clean fuel" narrative. The new measurement rules will determine whether LNG carriers and dual-fuel vessels get credit for lower CO2 or get penalized for higher methane. A correspondence group has been working on procedures since MEPC 83 and reports at this session.

Who's affected: The 900+ LNG-fueled vessels in operation and the 500+ on order. If methane-slip penalties are stringent, the business case for LNG as a transition fuel weakens significantly. Shipowners who ordered dual-fuel tonnage betting on LNG's regulatory advantage are watching this closely.

Battle 3: Onboard Carbon Capture — China Pushes Forward

MEPC 84 will consider draft guidelines for testing, survey, certification, and approval of onboard carbon capture and storage (OCCS) systems. China has been the loudest advocate, calling for faster progress on OCCS rules to give operators a compliance pathway that doesn't require new fuels.

The stakes: If OCCS is recognized as a valid compliance mechanism under the net-zero framework, it could transform the retrofit market. Vessels that can't switch to alternative fuels could instead install capture systems. But critics argue OCCS creates a moral hazard — allowing continued fossil fuel use while storing CO2 in tanks that must be offloaded at port.

Who's affected: Older tonnage that can't be economically retrofitted for alternative fuels. Bulk carriers and tankers built in the 2010s are the prime candidates. If OCCS guidelines are adopted, it creates a new equipment market worth billions.

Battle 4: North-East Atlantic Emission Control Area

MEPC 83 approved a proposal to designate the North-East Atlantic as an Emission Control Area for NOx, SOx, and particulate matter. MEPC 84 is expected to formally adopt the designation. If adopted, the earliest entry into force is March 2027 for NOx, with a one-year grace period for SOx/PM requirements entering force in 2028.

This extends the strictest emission standards from the Baltic and North Sea into the wider Atlantic — affecting routes between Northern Europe, the UK, Iceland, and the Iberian Peninsula.

Who's affected: Every vessel transiting Northern European waters. Operators not already using 0.10% sulphur fuel or exhaust gas cleaning systems in these waters will need to comply. Scrubber-fitted vessels have an advantage; others face higher fuel costs or capital expenditure on abatement equipment.

Battle 5: Plastic Litter Strategy — Zero Discharge by 2030

MEPC is expected to adopt a new 2026 Strategy and Action Plan to achieve zero plastic waste discharges to sea from ships by 2030. This updates the 2021 Strategy and will include mandatory garbage management provisions.

While less commercially impactful than the GHG fights, this signals IMO's expanding regulatory ambition beyond emissions into broader environmental governance.

Battle 6: Short-Term GHG Measures Review — Phase 2

MEPC will initiate the second phase of reviewing the short-term GHG reduction measures (CII and EEXI) adopted in 2021 and in force since 2022. This is significant because Phase 1 review identified implementation issues — particularly with the Carbon Intensity Indicator's methodology, which many operators argue penalizes certain vessel types unfairly.

Phase 2 could lead to recalibration of CII ratings, changes to correction factors, or adjustments to the trajectory of required improvements. Any vessel currently rated D or E has a direct stake.

Battle 7: Ballast Water Convention Amendments

MEPC is expected to approve a package of amendments to the Ballast Water Management Convention following its experience-building phase review. Revised guidelines for ballast water management plans will also be adopted.

For operators, the key question is whether the amendments ease any compliance burdens identified during implementation or add new requirements.

The Hormuz Connection

Here's what nobody else is saying: the Hormuz crisis and MEPC 84 are not separate stories. The same vessels stranded in the Gulf with expiring certificates will face new emission requirements when they finally sail. Operators managing war-risk premiums are simultaneously budgeting for carbon compliance costs. And the net-zero framework's US opponent is the same administration managing the Hormuz ceasefire.

The regulatory fragmentation risk is real. If the US blocks the IMO framework while the EU charges ahead with its ETS, shipping faces a split regulatory regime — one set of rules for European trades, another for the rest of the world. That fragmentation adds compliance cost and complexity at exactly the moment operators can least afford it.

Bottom Line

MEPC 84 won't produce a single headline as dramatic as the Hormuz crisis. But for a shipping operator's five-year budget, the decisions made in London from April 27 to May 1 may matter more than whatever emerges from Islamabad on April 10. The net-zero framework's trajectory, methane measurement rules, carbon capture recognition, and a new emission control area will collectively reshape the cost structure of international shipping. The operators who are paying attention to both crises — the geopolitical one at Hormuz and the regulatory one at IMO — are the ones who will navigate the next decade successfully.