Dangerous goods are not a category of cargo; they are a category of liability. The rules are strict because the failure mode is a fire at sea with no fire brigade.
01The nine classes
| Class | Hazard | Everyday examples |
|---|---|---|
| 1 | Explosives | Fireworks, airbag inflators, ammunition |
| 2 | Gases | Aerosols, LPG, refrigerant gas, fire extinguishers |
| 3 | Flammable liquids | Paint, solvents, alcohol, perfume, adhesives |
| 4 | Flammable solids; spontaneously combustible; dangerous when wet | Matches, sulphur, calcium carbide |
| 5 | Oxidising substances and organic peroxides | Hydrogen peroxide, fertiliser, pool chemicals |
| 6 | Toxic and infectious substances | Pesticides, diagnostic specimens |
| 7 | Radioactive material | Medical isotopes, industrial gauges |
| 8 | Corrosives | Battery acid, sodium hydroxide, some cleaning products |
| 9 | Miscellaneous | Lithium batteries, dry ice, magnetised material, environmentally hazardous substances |
02The classification chain
- Obtain the Safety Data Sheet from the manufacturer. Section 14 gives the transport classification. If there is no SDS, there is no shipment.
- Confirm the UN number and proper shipping name in the IMDG Code (sea) or IATA DGR (air). The proper shipping name is prescribed text — you do not paraphrase it.
- Determine the packing group — I (high danger), II (medium), III (low). This drives packaging requirements.
- Check the special provisions and packing instructions for that entry. Many entries have exceptions, limited-quantity provisions, or outright prohibitions.
- Check mode restrictions. Plenty of substances that travel by sea are forbidden by air, and passenger-aircraft limits differ from cargo-aircraft limits.
03The Shipper's Declaration
The DGD is signed by the shipper, not by us. It states that the consignment is correctly classified, packed, marked, labelled and in proper condition for transport.
Our responsibility is to check it is complete and consistent — UN number, proper shipping name, class, packing group, quantity per package, number of packages, packing instruction, and emergency contact — and to refuse it when it is not.
04Lithium batteries — the one you will meet most
The most commonly mis-shipped DG in the world, because the goods look ordinary.
- UN 3480 / UN 3090 — batteries shipped alone (lithium-ion / lithium-metal). The strictest category.
- UN 3481 / UN 3091 — batteries packed with equipment.
- UN 3481 / UN 3091 — batteries contained in equipment. The most permissive, still regulated.
State of charge matters: lithium-ion cells shipped alone by air must be at ≤30% state of charge. Watt-hour rating must be marked on the cell or battery. Section II / excepted quantities have their own marks and limits, and those limits change — check the current edition, not last year's memory.
05Undeclared DG
Shipping DG as general cargo is the most serious failure in this business. It has caused vessel losses and aircraft losses with fatalities. Consequences include criminal prosecution, unlimited liability, and immediate loss of carrier relationships.
Red flags in a booking:
- Vague descriptions: "chemicals", "samples", "electronic devices", "machine parts"
- Any product containing a battery, however small
- Cosmetics, perfume, nail polish, hand sanitiser
- Anything pressurised, aerosolised, or in a spray can
- Paints, inks, resins, adhesives, cleaning agents
- A shipper who becomes evasive when you ask for the SDS
When in doubt, request the SDS. A booking delayed by a day is cheaper than any of the alternatives.