On June 28, 2026, the IMO’s MEPC 85 formally approved an amendment to MARPOL Annex VI that brings SCR ammonia slip control into mandatory compliance, including a limit of no more than 10 ppm and a real-time AMMS requirement. The rule is set to take effect globally from January 2027 and applies to newly built and significantly retrofitted LNG- and methanol-fueled vessels. For shipowners, EPC contractors, and Chinese SCR system exporters, the development is worth close attention because it moves ammonia slip from a design consideration into a compliance item tied directly to procurement, equipment selection, and certification pathways.

What the MEPC 85 decision formally establishes

According to the information provided, the IMO approved amendments to MARPOL Annex VI at the MEPC 85 meeting held on June 28, 2026. The approved amendment makes two elements mandatory for compliance in relevant SCR applications: an ammonia slip limit of no more than 10 ppm and a real-time online monitoring module identified as AMMS.

The scope described in the provided information covers all newly built LNG and methanol dual-fuel vessels, as well as vessels in this category undergoing major retrofit. The implementation timing stated in the input is January 2027 for global effect.

The same information also indicates that the decision is directly relevant to overseas shipowner purchasing decisions, EPC contractor equipment selection, and the export certification route for Chinese SCR system suppliers.

Where the impact is likely to be felt first

Procurement decisions will become more specification-driven

Analysis shows that shipowners and other buyers are likely to feel the impact first at the specification and vendor-evaluation stage. Once ammonia slip limits and real-time monitoring become mandatory, purchasing decisions are less likely to focus only on general SCR functionality and more likely to examine whether the proposed configuration can support compliance in a documented and verifiable way.

What deserves closer attention is the shift in procurement language: buyers may place greater emphasis on monitoring capability, compliance documentation, and integration readiness when comparing systems for newbuilds and major retrofits.

Equipment selection pressure will rise for EPC contractors

From an industry perspective, EPC contractors are likely to see the rule reflected in technical selection, package coordination, and project definition. Because the requirement now covers both an ammonia slip threshold and a real-time AMMS function, the selection process may become more sensitive to how SCR systems and monitoring modules are paired within the overall vessel solution.

The practical impact is likely to appear in front-end engineering, bid clarification, and owner-contractor communication. Contractors will need to pay closer attention to whether selected equipment aligns with the mandatory compliance framework described in the amendment.

Export-oriented SCR suppliers face a clearer compliance gate

Analysis shows that Chinese SCR system suppliers serving overseas marine projects may be affected through export qualification and customer acceptance. The information provided explicitly links the new rule to export certification pathways, which suggests that compliance positioning may become a more central part of sales and project support discussions.

For suppliers, the most relevant business stages are likely to include product offering definition, certification preparation, technical submission, and communication with overseas clients and integrators. The issue is no longer only whether a supplier can provide an SCR system, but whether the supplied solution fits the mandatory compliance direction now confirmed by the IMO decision.

What companies should watch in the next stage

Track how the approved rule is expressed in practical compliance terms

Observably, one of the first priorities for market participants is to follow how the approved amendment is reflected in formal compliance language, project documents, and customer requirements. The approval itself is a confirmed fact, but companies still need to watch how the mandatory elements are referenced in actual transactions and technical review processes.

Separate policy confirmation from project execution detail

What deserves closer attention is the difference between a clear policy signal and day-to-day project implementation. The rule confirms the direction of compliance, but companies involved in bidding, engineering, and delivery should distinguish between what is already mandatory in principle and what must still be translated into concrete owner specifications, EPC requirements, and certification documentation.

Review documentation readiness for cross-border projects

For exporters and project suppliers, documentation readiness is likely to become more important. Analysis shows that customer communication, technical files, compliance statements, and certification-related materials may play a larger role once buyers and contractors begin aligning purchase packages with the new rule.

Prepare for longer alignment cycles in retrofits and newbuild coordination

From an operational perspective, companies involved in retrofit or newbuild delivery should watch for longer coordination cycles among owners, EPC contractors, and equipment suppliers. The reason is straightforward: once monitoring becomes mandatory alongside the ammonia slip limit, technical alignment may require earlier clarification during solution definition and contract discussion.

Why this reads as more than a routine technical update

Analysis shows that this development is better understood as a concrete compliance signal rather than a routine technical note. The rule does not merely restate a preferred emissions practice; it places a defined ammonia slip ceiling and real-time monitoring into the mandatory framework for relevant vessel categories.

At the same time, it is more appropriate to understand this as a rule with immediate directional clarity but ongoing implementation implications. The confirmed facts are already clear enough to influence market behavior, especially in procurement and equipment selection, yet the full business impact will depend on how shipowners, EPC firms, and suppliers translate the approved standard into project execution and certification work.

How to interpret the signal now

The immediate significance of the MEPC 85 decision lies in compliance becoming more explicit for SCR ammonia slip control on relevant LNG and methanol dual-fuel vessels. For the industry, the decision matters less as a headline and more as a practical marker for future purchasing, engineering, and export qualification discussions.

A neutral reading is that this is neither a short-lived update nor a fully exhausted policy story. It is more appropriate to understand it as a confirmed regulatory milestone with near-term commercial consequences and a need for continued observation as market participants turn the approved rule into actual project requirements.

Basis of this article and points that still require verification

This article is based on the user-provided news title, event date, and event summary. It does not rely on any additional unverified figures, company statements, project details, or market data.

For this type of development, commonly relevant source categories may include official IMO releases, formal regulatory texts, industry association updates, company announcements, authoritative media coverage, and standard-setting documents. A specific official source link was not provided in the input, so the exact documentary reference still requires ongoing verification.

Areas that remain worth tracking include how the approved amendment is cited in formal compliance documents, how buyers and EPC contractors reflect the rule in technical requirements, and how certification expectations develop for export-oriented SCR suppliers.