IMO Marine Environmental Protection Committee 83rd session (MEPC 83) was held from 7 to 11 April 2025. Key outcomes from the meeting are as follows:

1. Approved the Short-term and Mid-term measures for reducing GHG emissions from international shipping
Adopted the amendments to the Carbon intensity (CII) reduction factors for 2027-2030: IMO had completed the Phase 1 review of IMO's short-term GHG reduction measures. Under Phase 1, the Committee gathered data from Member States about their experience implementing the short-term measures, analyzed this data, and identified a list of challenges and/or gaps. 

MEPC 83 agreed on a work plan for Phase 2 of the review of the short-term GHG reduction measures, to run from Spring 2026 to Spring 2028. Phase 2 will look at enhancing the SEEMP framework, further developing CII metrics, as well as ensuring synergies between the IMO carbon intensity/energy efficiency framework and the IMO Net-Zero Framework.

2. Agreed to update the data in the IMO data collection system (DCS) on ship fuel consumption
MEPC approved amendments to regulation 27 of MARPOL Annex VI concerning accessibility to the IMO Ship Fuel Oil Consumption Database (IMO DCS), and the associated guidelines on data management. The IMO DCS requires ships to record and report their fuel oil consumption, and this data is subsequently used to calculate the ship's operational carbon intensity index (CII). 
The amendment will ensure that all reported data is available to Parties to Annex VI in a non-anonymized form. Once the amendments enter into force, public user accounts will be able to access a database with anonymized aggregated data, where identification of specific ships will not be possible.

3. Adopted amendments to MARPOL Annex VI and the NOx Technical Code to allow for the use of multiple engine operational profiles
FAL has approved the work plan for the development of a comprehensive IMO Strategy on Maritime Digitalization, which aims at harnessing emerging technologies to enhance efficiency, safety, and sustainability in the shipping industry. 
FAL formed a Correspondence Group to continue work to define the strategy’s scope, key objectives, and implementation framework. The Correspondence Group will work over the coming year to identify existing and emerging technologies, standards, and methodologies that can support maritime digitalization, while ensuring alignment across IMO’s various committees, and will submit a report for consideration at the next session Committee (FAL 50).

4. Guidelines for the development of the Inventory of Hazardous Materials (IHM)
MEPC adopted the amendments to the 2023 Guidelines for the development of the Inventory of Hazardous Materials (IHM Guidelines) (Res. MEPC.379(80)) were clarifying the relevant threshold for cybutryne contained in antifouling systems when samples are taken directly from the hull or from wet paint containers.
The development of the Inventory of Hazardous Materials is related to the Hong Kong International Convention for the Safe and Environmentally Sound Recycling of Ships (Hong Kong Convention).
5. Agreed to an experience-building phase for the Hong Kong Convention on ship recycling
The Hong Kong Convention (HKC) will take entry into force in June 2025, heralding a new era in ship recycling by introducing safety, human health, and environmental requirements at the end of the life of ships. 
By facilitating a smooth implementation of the HKC during the experience-building phase, stakeholders can work towards a cohesive approach that not only adheres to international norms but also supports continuous improvement and transparency.
6. Approved the including the development of a legally binding instrument on biofouling Convention on Biofouling
IMO approved the Guidance on in-water cleaning of ships' biofouling, which will be addressed as the circular MEPC.1/Circ.918. The Guidance on in-water cleaning of ships is to support the 2023 Biofouling Guidelines as well. MEPC had agreed on the new output on the “Development of a legally binding framework for the control and management of ships' biofouling to minimize the transfer of invasive aquatic species- a biofouling Convention.”
References:
1. American Bureau of Shipping (ABS), News Brief: MEPC 83. https://ww2.eagle.org/content/dam/eagle/regulatory-news/2025/MEPC-83-Brief.pdf 
2. Det Norske Veritas (DNV), IMO MEPC 83: GHG Requirements Approved, Taking Effect from 2028. News from DNV. https://www.dnv.com/news/imo-mepc-83-ghg-requirements-approved-taking-effect-from-2028/ 
3. InterManager, Summary report on IMO Marine Environment Protection Committee MEPC 83. https://www.intermanager.org/wp/wp-content/uploads/2025/04/IMO%20MARINE%20ENVIRONMENT%20PROTECTION%20COMMITTEE%2083,%207-11%20April%202025.pdf 
4. Lloyd's Register (LR), MEPC 83 Summary Report. https://maritime.lr.org/MEPC-83-Summary-Report 
5. ClassNK, Preliminary Report of MPEC 83. https://www.classnk.or.jp/hp/pdf/info_service/imo_and_iacs/MEPC83_sumE.pdf 
6. IMO, Marine Environment Protection Committee (MEPC 83), 7 to 11 April 2025. https://www.imo.org/en/MediaCentre/MeetingSummaries/Pages/MEPC-83rd-session.aspx 
7. 財團法人驗船中心，《MEPC 83會議快報》。https://www.crclass.org/wp-content/uploads/2025/04/MEPC83%E6%9C%83%E8%AD%B0%E5%BF%AB%E5%A0%B120250412.pdf  
8. 中國船級社，《MEPC 第83屆會議要點快報》。https://www.ccs.org.cn/ccswz/file/download?fileid=202504140874585632