Shipping Dangerous Goods: IMDG, IATA DGR and ADR Basics

Dangerous goods for exporters: the 9 hazard classes, UN numbers, packing groups, IMDG, IATA DGR, ADR and the DG declaration, with a worked perfume example.

Most exporters think dangerous goods are a matter for chemical companies. Then they ship a pallet of perfume, a carton of aerosol sprays, a machine with a lithium battery, paint samples or bags of charcoal, and discover that the shipment is refused, delayed, or accepted only after weeks of paperwork. Worse, some ship such goods without declaring them, and become liable for a fire on a container ship.

Dangerous goods (also called hazardous materials or hazmat) are substances and articles that can endanger people, ships, aircraft, vehicles or the environment during transport. Their carriage is regulated in detail by international codes for each mode, and the shipper carries the first and heaviest responsibility.

This lesson gives you the essentials: how to recognise a dangerous good, the nine hazard classes, the identifiers used everywhere (UN number, proper shipping name, packing group), the main modal rules, the documents, and the practical steps to book a shipment. It does not replace the regulations or the training they require.

Why dangerous goods rules matter to every exporter

Undeclared or misdeclared dangerous goods are a recurring cause of fires on container ships, with losses running into hundreds of millions of dollars and, sometimes, lives lost. Carriers now screen bookings with software that looks for suspicious descriptions, and penalties for misdeclaration are heavy.

As shipper you are responsible for:

1. classifying the goods correctly;
2. packing them in suitable, usually UN-approved, packaging;
3. marking and labelling the packages;
4. documenting them with a signed dangerous goods declaration;
5. ensuring the staff who do this are trained, as each modal regulation requires.

A forwarder can help, and many offer dangerous goods services, but it relies on your information. The safety data sheet (SDS) from the manufacturer, section 14 in particular, is the starting point for classification.

The nine classes of dangerous goods

A product can have a main hazard and one or more subsidiary hazards, and some substances are also marine pollutants, which adds a specific mark for sea transport.

How is a dangerous good identified?

• UN number: a four-digit number for the substance or group, such as UN 1266 (perfumery products) or UN 3481 (lithium-ion batteries contained in equipment).
• Proper shipping name: the official name attached to the UN number, used in documents ("PERFUMERY PRODUCTS").
• Class or division: the hazard, with any subsidiary hazard.
• Packing group: I (high danger), II (medium) or III (low), for most classes; it decides the packaging standard.
• Special provisions, limited and excepted quantities: the dangerous goods list for each UN number states what quantities qualify for simplified rules.

Limited quantities (LQ) are small inner packagings within a maximum per UN number (for example up to 5 litres per inner packaging for many class 3 liquids of packing group II or III by sea), packed in strong outer packaging. They benefit from simplified marking (the LQ diamond) and no hazard labels, but they remain dangerous goods and must be declared for sea transport. Excepted quantities are even smaller amounts with further relief.

Which regulations apply to each mode?

All modal rules are based on the UN Recommendations on the Transport of Dangerous Goods (the "Orange Book"):

Air rules are the strictest: a product accepted by sea as a limited quantity may be forbidden on a passenger aircraft. Express couriers add their own restrictions and often refuse dangerous goods from occasional shippers.

Documents for a dangerous goods shipment

• Dangerous goods declaration (DGD): for sea, a document giving the UN number, proper shipping name, class, packing group, number and type of packages, quantity, flash point where relevant, marine pollutant status, emergency contact, and a signed shipper's certification. The multimodal dangerous goods form, recommended by the IMO and UNECE, serves the purpose.
• Container packing certificate: signed by the person responsible for packing the container, confirming it was packed, segregated and secured in accordance with the IMDG Code. It is often combined with the DGD on the multimodal form.
• Shipper's Declaration for Dangerous Goods: for air, in the IATA format, signed by trained staff.
• ADR transport document: for road; the carrier provides the driver with the instructions in writing for emergencies.
• Safety data sheet: not a transport document as such, but carriers usually ask for it.

Packages must bear UN specification marks (showing they passed the required tests), the UN number and proper shipping name, hazard labels, and the marine pollutant or LQ marks where applicable. Containers and vehicles carrying dangerous goods display placards. See packaging and marking for the general marking rules.

How to book a dangerous goods shipment

1. Obtain the SDS and confirm the classification for the mode (UN number, class, packing group, LQ eligibility).
2. Ask your freight forwarder or the carrier for DG acceptance: send the UN number, proper shipping name, class, packing group, quantities, packaging and SDS. Allow several days.
3. Check the restrictions: some carriers, vessels, transshipment ports and LCL consolidators refuse certain classes; segregation rules may prevent mixing with other cargo.
4. Use approved packaging, mark and label it, and have trained staff prepare the declaration.
5. Pack and secure the container under the IMDG and CTU Code rules, and sign the container packing certificate.
6. Expect DG surcharges and longer cut-offs.

Worked example: perfumes in groupage to Marseille

A cosmetics maker in Algiers ships 6 pallets of alcohol-based perfumes in 100 ml glass bottles to a distributor in Marseille, LCL by sea.

• Classification (from the SDS): UN 1266, PERFUMERY PRODUCTS, class 3, packing group II (flash point below 23 °C).
• Limited quantity: by sea, UN 1266 in packing group II allows up to 5 litres per inner packaging. Each 100 ml bottle qualifies, packed in strong cartons of no more than 30 kg gross. The cartons carry the LQ mark instead of class 3 labels.
• Documents: a DGD stating "UN 1266, PERFUMERY PRODUCTS, 3, PG II, LIMITED QUANTITY", with the number of cartons and the total net quantity in litres; the SDS; the commercial invoice and packing list showing the same description.
• Booking: the first consolidator contacted refuses class 3 on its Marseille groupage; the second accepts LQ cargo on its weekly service with a dangerous goods surcharge of EUR 85 and a cut-off two days earlier than general cargo.
• Samples by air: the same week, the exporter wants to send 20 bottles to a trade fair in Dubai by courier. The courier refuses dangerous goods from non-contracted shippers, so the samples go as air cargo via a forwarder with a trained DG agent, under the IATA rules for limited quantities.

Common mistakes with dangerous goods

• Not recognising that a product is dangerous (perfume, aerosols, batteries in equipment, charcoal, sanitiser).
• Relying on an old or foreign SDS without checking section 14.
• Using ordinary cartons where UN-specification packaging is required.
• Letting untrained staff sign declarations.
• Booking LCL or courier without checking acceptance first.
• Inconsistent descriptions between the DGD, the invoice and the bill of lading.
• Forgetting that the rules change: the IMDG Code every two years, the IATA DGR every year. The transport modes lesson helps you weigh the mode choice for regulated goods.