If your business moves goods by sea — whether as a shipper, freight forwarder, shipping line, or port operator — the IMDG Code is the rulebook. It governs how dangerous goods are classified, packaged, documented, and handled on international voyages. Here is a plain-language guide to what it is and why it matters.

What Is the IMDG Code?

The International Maritime Dangerous Goods (IMDG) Code is published by the International Maritime Organization (IMO).^{[ 1 ]} It is the globally accepted standard for the transport of dangerous goods by sea, covering everything from industrial chemicals and explosives to batteries, paints, and aerosols.

The IMDG Code is made mandatory under Chapter VII of the SOLAS Convention (International Convention for the Safety of Life at Sea),^{[ 2 ]} which means compliance is a legal requirement for vessels engaged in international voyages. Australia, as a signatory to SOLAS, requires Australian-flagged ships and international vessels calling at Australian ports to comply with the IMDG Code.

What Does the IMDG Code 2024 Cover?

The IMDG Code is a comprehensive document covering the classification of dangerous goods across nine classes — from explosives (Class 1) through flammable liquids (Class 3), toxic substances (Class 6), radioactive materials (Class 7), and corrosives (Class 8), to miscellaneous dangerous substances (Class 9).

For each substance or article, the Code specifies the UN number, proper shipping name, class and packing group, packing instructions, quantity limits, labelling and marking requirements, placarding requirements for containers, segregation rules (which goods must not be stowed together), and the documentation required for the shipment.

It also includes emergency response guidance and provisions for the reporting of dangerous goods incidents at sea.

Who Is Required to Use the IMDG Code?

The IMDG Code applies to everyone in the maritime supply chain who handles international shipments of dangerous goods. This includes exporters and importers preparing dangerous goods consignments, freight forwarders and customs brokers, shipping lines and vessel operators, container packing operators and depot staff, and port authorities and stevedores.

In Australia, AMSA (Australian Maritime Safety Authority) is the competent authority responsible for enforcing IMDG Code compliance.^{[ 3 ]} Non-compliance can result in refusal of cargo, detention of vessels, substantial fines, and in the event of an incident, significant legal liability.

See also: Dangerous Goods Compliance in Australia: Road, Air and Sea Requirements

The Current Edition: IMDG Code Amendment 42-24

The current edition of the IMDG Code is Amendment 42-24. It was available for voluntary application from 1 January 2025 and became mandatory on 1 January 2026, replacing Amendment 41-22. This edition introduced a range of updates to dangerous goods entries, packing instructions, and provisions related to lithium batteries, including updates to stowage and segregation requirements.^{[ 1 ]}

The IMDG Code is published in two volumes and a supplement. The supplement contains, among other things, the Emergency Response Procedures for Ships Carrying Dangerous Goods (EmS Guide), the Medical First Aid Guide (MFAG), and the Reporting Procedures. Most operations require access to the full set.

Lithium Batteries Under the IMDG Code

Lithium batteries are subject to specific requirements under the IMDG Code, including stowage, segregation, and documentation rules. Amendment 42-24 updated a number of provisions relating to lithium battery transport by sea. If your business ships devices, power tools, or other battery-containing goods internationally, it is worth reviewing these provisions in detail.

See also: Shipping Lithium Batteries by Air and Sea: What the Regulations Actually Require

Printed or Digital IMDG Code?

The IMDG Code is available in both printed and digital formats. Many professionals prefer a physical copy for daily desk reference — it is a working document that gets opened constantly, annotated, and checked against shipment paperwork. Digital versions offer the advantage of searchability and are particularly useful for organisations managing multiple editions or needing access from multiple locations.

For Australian buyers, the geographical distance from the UK — where printed books are held — means that digital delivery is often faster and more practical, particularly where time-sensitive compliance decisions are involved.