IMDG Amendment 42-24: China Dangerous Goods Shipping Rules Are Live : What Every Importer Must Know

On January 1, 2026, IMDG Amendment 42-24 became mandatory for all ocean freight shipments worldwide. For companies importing battery-powered products, electric vehicles, e-bikes, e-scooters, lithium batteries, sodium-ion batteries, and energy storage systems from China, this is not a minor technical update. It is a structural change to how every one of those shipments must be classified, documented, packaged, and declared. The generic UN 3171 classification that covered all battery-powered vehicles for decades is no longer permitted for lithium-ion or sodium-ion powered vehicles. Three new specific UN numbers replace it. Sodium-ion batteries are classified as Class 9 Dangerous Goods for the first time in the IMDG Code’s history, having previously moved as general cargo. Carbon and charcoal products now require mandatory date and temperature documentation that did not exist before. Shipping lines employing trained dangerous goods specialists are rejecting bookings where the documentation does not align with IMDG Amendment 42-24. Importers whose suppliers are still declaring shipments under the old codes are having containers rejected at booking, held at Chinese ports, or detained by destination customs authorities. This guide explains every IMDG Amendment 42-24 change that matters to importers sourcing from China, what the new documentation requirements are, and what must happen on every shipment before a booking is confirmed.

IMDG Amendment 42-24: The Four Changes That Matter to Importers

The International Maritime Organization publishes updates to the IMDG Code in two-year cycles. Amendment 42-24 was published in 2024 with a voluntary implementation period throughout 2025. From January 1, 2026, the amendment is mandatory, subject to national implementation and carrier enforcement timelines. Any shipment of dangerous goods by sea from any origin, including China, that does not comply with Amendment 42-24 is non-compliant regardless of what the previous IMDG version permitted. The changes divide into four commercially significant areas:

Change 1: UN 3171 Is Dead for Lithium and Sodium-Ion Vehicles

UN 3171, described as “Battery-powered vehicle, Class 9,” was the generic classification used for all electric and battery-powered vehicles and conveyances under the old IMDG regime. It covered e-bikes, e-scooters, golf carts, electric forklifts, electric cars, and any other battery-powered vehicle regardless of the battery chemistry involved. Under IMDG Amendment 42-24, UN 3171 is no longer permitted for shipments where the vehicle is powered by a lithium-ion, lithium metal, or sodium-ion battery. Three specific entries replace it:

The correct UN number must correspond to the specific battery chemistry in the vehicle being shipped. An e-bike powered by a lithium-ion pack must be declared UN 3556. An e-scooter powered by the newer sodium-ion battery technology must be declared UN 3558. Maersk’s January 2026 advisory explicitly confirms that UN 3171 is no longer permitted for lithium or sodium-ion powered vehicles and that all applicable shipments must use the new specific entries. Any documentation received from a Chinese supplier after January 1, 2026 that still shows UN 3171 for an e-bike, e-scooter, or other battery-powered vehicle is incorrect and will cause the shipment to be rejected at booking or held at the port.

Change 2: Sodium-Ion Batteries Are Now Class 9 Dangerous Goods

This is the most commercially significant new classification in IMDG Amendment 42-24. Sodium-ion batteries, which power a growing category of Chinese-manufactured battery packs, energy storage systems, and a new generation of electric vehicles, were not classified as dangerous goods under the previous IMDG Code. They moved as general cargo. From January 1, 2026, sodium-ion batteries with organic electrolytes are Class 9 Dangerous Goods with two new UN numbers:

• UN 3551: Sodium-ion batteries, including sodium-ion battery packs, standalone sodium-ion battery cells and modules with organic electrolytes
• UN 3552: Sodium-ion batteries contained in equipment or packed with equipment, with organic electrolytes

Sodium-ion batteries are also now subject to the Lithium Battery Mark and Class 9 label requirements on packaging. This means that importers who were previously receiving sodium-ion battery products from China with no dangerous goods documentation are now importing Class 9 DG that requires full DG handling, DG-certified vessel booking, Class 9 labels, and the complete documentation set including Safety Data Sheet referencing Amendment 42-24. Any importer of sodium-ion battery products whose freight forwarder has not updated their DG classification procedure is moving undeclared dangerous goods on every shipment. That creates cargo seizure risk, vessel liability risk, and insurance coverage gaps on every ocean shipment.

Change 3: Carbon and Charcoal Products Now Require Date and Temperature Documentation

While batteries and EVs are the headline change, IMDG Amendment 42-24 also affects raw material importers. Previously exempt carbon and charcoal products, including activated carbon, are now subject to enhanced documentation requirements under Amendment 42-24. Transport documents for carbon-based shipments must now include three specific data points that were not previously required:

• Date of production
• Date of packaging
• Temperature of the material at the time of packaging

Carbon products that do not include this information on the transport document are non-compliant under Amendment 42-24. For importers of activated carbon, carbon black, charcoal, and related materials from China, the commercial invoice and transport document template must be updated to capture and transmit this data from the manufacturer before each shipment. Some previously exempt activated carbon categories are now subject to full DG declaration and self-heating controls. Confirm the specific classification of your carbon product with a DG specialist before assuming the previous exemption still applies.

Change 4: Documentation Consistency Is Now the Primary Enforcement Point

Amendment 42-24 has moved enforcement upstream. Shipping lines employing trained dangerous goods specialists now cross-reference multiple documents before accepting any hazmat cargo booking. The documents that must be perfectly consistent with each other are:

• Safety Data Sheet (SDS): Section 14 of the SDS, specifically the transport and regulatory information section, must reference IMDG Code Amendment 42-24. An SDS that references the previous IMDG version is no longer compliant regardless of whether the physical product has changed
• Dangerous Goods Declaration (DGD): Must state the correct new UN number (3556, 3557, or 3558 for vehicles; 3551 or 3552 for sodium-ion batteries), the correct Proper Shipping Name, and the correct Packing Instruction (P912 for vehicles)
• UN 38.3 Test Report: The battery parameters in the test report must match the specifications in the commercial documents. Any discrepancy between the test report wattage, chemistry, or cell configuration and the commercial invoice description triggers rejection
• Battery Specification Sheet: Must align with the UN 38.3 test report parameters in every technical detail
• Commercial Invoice: Must describe the goods in a way that is consistent with the DGD and SDS descriptions. A commercial invoice that describes “electric scooters” while the DGD uses technical DG language creates a mismatch that DG specialists flag
• Packaging Certificate: Must confirm compliance with the applicable Packing Instruction. For UN 3556-3558 vehicles, that is Packing Instruction P912. The certificate must reference P912 explicitly
• Container Placarding: Maersk’s January 2026 advisory recommends that hazardous containers subject to Special Provision 962 be placarded on all four sides rather than the standard two-side requirement, to account for varying port interpretations. Verify placarding before gate-in to avoid rejection

Any inconsistency across any of these documents triggers a booking rejection. Re-booking after rejection typically extends the supply chain timeline by two to four weeks as corrected documents are obtained from the Chinese manufacturer, resubmitted to the shipping line, and accepted before a new booking slot is allocated.

The Three Most Common Failure Scenarios

Scenario 1: Supplier Still Using UN 3171

A Chinese e-bike manufacturer ships a container of lithium-ion powered e-bikes to a UK importer. The DGD shows UN 3171 because the manufacturer’s documentation template has not been updated since December 2025. The shipping line’s DG desk rejects the booking. The manufacturer must update the DGD to UN 3556, update the SDS Section 14 to reference Amendment 42-24, and resubmit before a new booking slot can be allocated. Estimated delay: two to three weeks. For importers with seasonal demand cycles, a two-week delay on a peak season shipment is a commercial event, not an administrative inconvenience.

Scenario 2: Sodium-Ion Product Shipped as General Cargo

A UK importer sources a 20-foot container of sodium-ion battery packs from a Shenzhen manufacturer. The manufacturer has been supplying these products for two years. Before January 1, 2026, they shipped as general cargo with no DG paperwork. After January 1, 2026, they are Class 9 Dangerous Goods requiring UN 3551 classification, Class 9 labels, Lithium Battery Mark on outer packaging, SDS Section 14 referencing Amendment 42-24, and a DG-certified vessel booking. The container arrives at Felixstowe without DG documentation. UK Border Force detains the container pending DG compliance review. The importer faces storage charges, reclassification costs, and potential penalties for undeclared dangerous goods.

Scenario 3: Document Mismatch Between SDS and DGD

A US importer orders lithium battery packs for data centre UPS systems. The manufacturer provides an updated DGD with the correct UN number. But the SDS provided still references the previous IMDG version in Section 14. The shipping line’s DG specialist flags the inconsistency and rejects the booking. The manufacturer must obtain a revised SDS from their chemical safety team specifically referencing Amendment 42-24. In China, SDS revision from a certified provider typically takes five to ten working days. Estimated delay: two weeks.

Five Actions Every Importer Must Take Before the Next Shipment

1. Confirm the battery chemistry of every product containing a battery. Lithium-ion, lithium metal, and sodium-ion batteries each have different UN numbers under Amendment 42-24. If your product contains a battery and you do not know the specific chemistry, request the battery specification sheet from your Chinese supplier before placing the order. The correct UN number flows from the correct chemistry identification. Getting this wrong produces incorrect paperwork that delays every shipment
2. Confirm your supplier has updated all documentation to reference IMDG Amendment 42-24. Request the current SDS and verify that Section 14 references IMDG Code Amendment 42-24 by name. Request the current DGD and verify it shows the correct new UN number rather than the generic UN 3171. Request the current Packaging Certificate and verify it references Packing Instruction P912 for vehicle products. Do this before the first shipment under the new rules, not after the first rejection
3. Instruct your freight forwarder to confirm DG-certified vessel availability before booking. Sodium-ion batteries and lithium batteries are Class 9 Dangerous Goods. Not all vessels or carriers accept Class 9 DG cargo on all routes. Carriers that accept Class 9 on the China-UK or China-US lane include Maersk, CMA CGM, Zim, and Matson, but vessel acceptance varies by departure port, terminal, and cargo mix. Confirm DG acceptance before booking, not at cut-off. Our Freight Forwarding service manages DG vessel booking on China-UK, China-US, and China-EU lanes with pre-confirmed carrier acceptance for Class 9 cargo on every shipment
4. Implement a four-side placarding protocol for containers subject to Special Provision 962. Maersk’s January 2026 advisory recommends that hazardous containers subject to SP 962 be placarded on all four sides rather than the standard two-side requirement, to account for varying port interpretations. Verify placarding before gate-in. A container returned from gate-in for incorrect placarding adds one to three days to the departure timeline
5. Update your supplier contract to require Amendment 42-24 compliant documentation on every shipment. The most common cause of booking delays is suppliers whose documentation templates have not been updated. A contractual requirement for Amendment 42-24 compliant DGDs, SDS documents referencing the current IMDG version, and P912-compliant packaging certificates puts the documentation obligation explicitly on the supplier with a commercial consequence for non-compliance. Understanding what an Importer of Record does in managing DG compliance documentation is the foundation of this obligation: the IOR named on the customs entry bears legal responsibility for the correctness of the dangerous goods classification and documentation at the point of import. Our IOR services include DG documentation review and Amendment 42-24 compliance verification on every China-origin DG shipment as part of the pre-clearance process

How Carra Globe Manages China Dangerous Goods Compliance

Carra Globe provides IOR services and Freight Forwarding for dangerous goods shipments from China to the UK, EU, US, and all major destination markets under IMDG Amendment 42-24. Our DG compliance team verifies that every China-origin shipment of battery products, electric vehicles, and other dangerous goods is declared with the correct Amendment 42-24 UN number, correctly classified battery chemistry, SDS Section 14 referencing the current IMDG version, P912-compliant packaging certification where applicable, and DG-certified vessel booking before any cargo moves. For importers of sodium-ion battery products who were previously shipping as general cargo, we manage the full transition to Class 9 DG compliance including UN 3551 or UN 3552 classification, carrier notification, Class 9 labelling, and Lithium Battery Mark application. Our Delivered Duty Paid service incorporates DG compliance, IOR clearance, and UK, EU, or US customs duty payment into a single end-to-end managed service for China-origin battery and EV shipments. For related compliance context, see our guide to lithium battery customs clearance and our guide to shipping AI servers internationally for the broader technology hardware import compliance picture.

Frequently Asked Questions: IMDG Amendment 42-24

Can I still use UN 3171 for e-bike shipments from China after January 2026?

No. UN 3171 is no longer permitted for e-bikes, e-scooters, or any other vehicle powered by a lithium-ion, lithium metal, or sodium-ion battery under IMDG Amendment 42-24. Use UN 3556 for lithium-ion powered vehicles, UN 3557 for lithium metal powered vehicles, and UN 3558 for sodium-ion powered vehicles. Any DGD submitted after IMDG Amendment 42-24 became mandatory showing UN 3171 for these product types will be rejected at booking by shipping lines enforcing the new rules. Enforcement varies by carrier but all major lines including Maersk, CMA CGM, and MSC are applying the new requirements.

Are sodium-ion batteries now dangerous goods?

Yes, from January 1, 2026. Sodium-ion batteries with organic electrolytes are now classified as Class 9 Dangerous Goods under Amendment 42-24. Standalone sodium-ion batteries are UN 3551. Sodium-ion batteries contained in or packed with equipment are UN 3552. They are also now subject to the Lithium Battery Mark and Class 9 label requirements on all outer packaging. Under IMDG Amendment 42-24, any sodium-ion battery product previously shipped from China as general cargo must now be shipped as Class 9 DG with full documentation.

What is Packing Instruction P912 and which products does it apply to?

P912 is the packing instruction introduced in Amendment 42-24 for battery-powered vehicles classified under UN 3556, 3557, and 3558. It specifies how vehicles powered by lithium-ion, lithium metal, or sodium-ion batteries must be packaged for ocean transport. The Packaging Certificate for any shipment of these vehicles must reference P912 to be compliant. P912 covers battery state of charge requirements, packaging integrity standards, and labelling requirements for the outer packaging of battery-powered vehicles.

Why is my supplier’s SDS not updated for IMDG Amendment 42-24?

SDS documents are produced by chemical safety specialists and updated on a separate schedule from shipping documentation. Many Chinese manufacturers updated their DGDs when Amendment 42-24 was announced but did not simultaneously commission updated SDS documents. Section 14 of the SDS must reference IMDG Code Amendment 42-24. An SDS still referencing the previous IMDG version will cause a booking rejection even if all other documentation is correct. Request a revised SDS from your supplier explicitly referencing Amendment 42-24 in Section 14 before your next shipment.

Does IMDG Amendment 42-24 apply to air freight as well as ocean?

IMDG governs ocean freight only. Air freight dangerous goods are governed by IATA DGR, which publishes its own annual update cycle. IATA DGR 67th Edition took effect January 1, 2026 with related changes to battery and EV classifications for air transport. The two frameworks are separate but largely aligned on battery chemistry classifications. If you ship battery products by both sea and air, confirm compliance with both IMDG Amendment 42-24 for ocean shipments and IATA DGR 67 for air shipments independently.

What happens if my container arrives at a UK or EU port with incorrect DG documentation?

Border authorities can detain the container pending DG compliance review and may impose penalties for undeclared dangerous goods depending on national enforcement policy. This triggers storage charges at the port, a formal DG reclassification process, potential penalties for undeclared or incorrectly declared dangerous goods, and a delayed release timeline that can extend to several weeks. For lithium battery and EV products, the penalties for undeclared DG can be material. The correct approach is to verify documentation before the container departs China, not after it arrives at the destination port.