Classification society DNV has issued instructions to ship owners, managers and suppliers following the June 2025 agreement by the 16 OSPAR contracting parties to phase out discharge from exhaust gas cleaning systems (EGCSs) in coastal waters of the European north-east Atlantic.
OSPAR is the Convention for the Protection of the Marine Environment of the North-East Atlantic, and it is the mechanism by which 15 governments and the EU cooperate to protect the marine environment of the region. The OSPAR contracting parties are Belgium, Denmark, Finland, France, Germany, Iceland, Ireland, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, the UK and the EU.
OSPAR contracting parties have agreed that discharge of wash water from EGCSs is to be banned in inland waters and port areas of OSPAR member states, from 1 July 2027 for open loop discharge, followed by a ban on all discharge from 1 July 2029. Contracting parties can delay the implementation by three years. OSPAR further recommends extending the ban to the territorial waters (12 naut mile) in general. A Working Group will review if this recommendation should be turned into a mandatory regulation.
The OSPAR Convention covers the north-east Atlantic. An extension of the ban to include the Mediterranean Sea will be up to Spain and France to decide. Denmark, Finland and Sweden already enacted discharge regulations starting in July 2025 from open-loop scrubbers covering their territorial waters (12 nm), which also include the Baltic Sea.
DNV points out that ships which can operate EGCS in zero-discharge mode should not have any issues with the upcoming ban on discharge water. However, holding tank capacity may limit operational flexibility for many ships.
Ships equipped with an open loop or hybrid EGCS without any holding tank capacity should plan for a zero-discharge upgrade ahead of the relevant compliance deadlines. If upgrading to a more advanced hybrid or zero-discharge configuration is not feasible, switching over to compliant fuel while in port areas remains the only viable compliance option.
Any modification to an approved EGCS will require amendment and approval of the relevant statutory documents and, where applicable, MED certification. Since conversion to hybrid mode affects system performance in terms of both air and water emissions, the latest scrubber guideline – MEPC.340(77), effective from 1 June 2022 – should be applied for statutory re-approval. Considering the significant changes introduced in this guideline compared to earlier revisions, upgrading older EGCSs to hybrid mode may also require additional system updates, including revisions of all related statutory documentation.
There may be several reasons for engaging a different company to carry out a scrubber modification project from that which originally designed and installed the EGCS. As much as this scenario is possible from the perspective of statutory approval, it has some consequences, especially considering document approval and MED certification:
If alteration approval follows the same scrubber guideline as the initial approval, revising the entire set of statutory documents may be avoided by preparing expressive addendums to the original document. If the EGCS needs to be re-approved according to MEPC.340(77), all statutory documents need to be revised by the manufacturer in charge and submitted for approval.
For installations subject to MED certification, a new application needs to be submitted. MED regulations only allow one single applicant for a complete EGCS. Consequently, the new applicant is taking over legal responsibility for the entire modified system. MED certification is usually applied for by the EGCS maker, who also needs to issue an EU Declaration of Conformity confirming fulfilment of the requirements relating to the product.
DNV recommends that shipowners with vessels trading in the north-east Atlantic and relying on open loop scrubbers for SOx emissions compliance should prepare for stricter discharge water regulations. Either switching to compliant fuel or upgrading to a hybrid scrubber system with a zero-discharge option could offer a practical alternative. Modified systems must comply with the latest version of MEPC.340(77).
Image: Scrubbers are to be subject to restrictions in NW European waters (source: DNV)
