IMDG Code Amendment 42‑24: Effective Dates and Transition

The IMO’s Maritime Safety Committee (MSC) approved Amendment 42-24 of the IMDG Code in May 2024 (Resolution MSC.556(108)). This 2024 Edition (Amendment 42-24) may be applied voluntarily from 1 January 2025 and will become mandatory on 1 January 2026. In practice, there is a one-year transition: during 2025, shippers can use either the older 2022 Code (Amendment 41-22) or the new 2024 Code. After 31 December 2025, only the 2024 Code is valid.

Key Updates in the IMDG Code 42‑24 Edition

· The 42-24 amendment introduces hundreds of changes. Major highlights include:

· • New dangerous goods entries: new UN numbers have been added for sodium‑ion batteries (UN 3551, 3552), vehicles powered by lithium-ion, lithium-metal or sodium-ion batteries (UN 3556–3558), fire-suppressant devices (UN 3559), tetramethylammonium hydroxide solution (UN 3560), and others.

· • Organic peroxides table revised: additions and amendments including UN 3105 and UN 3109.

· • Classifications and packaging: changes for carbon (UN 1361) and activated carbon (UN 1362); revised LP903 guideline for lithium battery transport packaging.

· • Stowage and segregation: updates for lithium battery modules (UN 3536), now only allowed on deck.

· • Labeling and documentation: simplifications for unboxed vehicles and reinforced documentation for exempted dangerous goods.

Voluntary Early Adoption of 42‑24

· • IMO allows Contracting Governments to voluntarily implement IMDG Code 42-24 starting 1 January 2025.

· • Ships registered in such countries may adopt the new Code early and remain compliant.

· • Port State Control authorities must respect each country's decision for its flagged ships.

Clarifying Voluntary Adoption Across Countries

· • From 1 January to 31 December 2025, both Amendment 41-22 and 42-24 are valid.

· • After 31 December 2025, only Amendment 42-24 will apply.

· • For example, Country A adopts 42-24 early, so its flagged vessels follow the new rules. Country B does not, so its ships continue using 41-22 until the mandatory date.

Implementation Status and China’s Position (as of April 15, 2025)

· • As of mid-April 2025, no country has submitted early adoption notification for Amendment 42-24 via IMO GISIS.

· • China has not yet filed such notice; thus, Chinese ships must follow Amendment 41-22 until 31 December 2025.

· • Since 2004, China has clarified rule enforcement through formal announcements ahead of any mandatory change.

Recommendations for Industry Professionals

· • Monitor updates from national transport and maritime authorities.

· • Train logistics and shipping personnel on key changes in classification, labeling, and documentation.

· • Prepare to update dangerous goods declarations and stowage plans.

· • Begin transitioning documentation and SOPs in Q3–Q4 2025 to ensure smooth compliance by January 2026.

References

International Maritime Organization (IMO). (2024). IMDG Code Amendment 42-24. Resolution MSC.556(108). London: IMO.

International Maritime Organization (IMO). (2017). MSC.1/Circ.1565 on Early Implementation of Mandatory IMO Instruments. London: IMO.

International Maritime Organization (IMO). (2024). IMDG Code Supplement, 2024 Edition. London: IMO.

Ministry of Transport of the People's Republic of China. (2025). Notices on Maritime Dangerous Goods Transport Regulations. Beijing: MOT.

International Maritime Organization (IMO). GISIS Database. Accessed April 15, 2025.