How many IMO dangerous goods classes are there?

Nine. Several are split into divisions — class 2 into flammable, non-flammable and toxic gases, for example — and the division usually decides the handling more than the class does.

Which class do lithium batteries fall under?

Class 9, miscellaneous. They are the reason many shippers meet dangerous goods rules for the first time, and the packing and state-of-charge requirements are strict.

Does the class alone decide whether a carrier will take the cargo?

No. Carrier acceptance policy, port and terminal restrictions, packing group and the specific UN number all sit on top of the class. A substance acceptable on one service may be refused on another.

IMO Dangerous Goods Classes — All 9 Classes

The class is where the question starts, not where it ends. Carrier acceptance policy, terminal restrictions and the specific UN number all sit on top of it, and they differ by service and by port. Confirm with your carrier before booking.

Class 1 — Explosives

Substances and articles capable of a mass explosion, projection or fire hazard. Segregation and stowage are tightly prescribed and many carriers decline them outright.

Typically includes: Blasting agents, fireworks, ammunition, airbag inflators.

1.1Mass explosion hazard
1.2Projection hazard, no mass explosion
1.3Fire hazard, minor blast or projection
1.4No significant hazard
1.5Very insensitive, mass explosion hazard
1.6Extremely insensitive, no mass explosion hazard

Class 2 — Gases

Gases compressed, liquefied, dissolved or refrigerated. The division decides the handling: a flammable gas and an inert one travel under very different rules.

Typically includes: Propane, nitrogen, aerosols, oxygen, chlorine.

2.1Flammable gases
2.2Non-flammable, non-toxic gases
2.3Toxic gases

Class 3 — Flammable liquids

Liquids giving off a flammable vapour at or below a defined flashpoint. One of the most frequently shipped classes, and one where packing group matters as much as class.

Typically includes: Paints, solvents, alcohols, petrol, many adhesives.

Class 4 — Flammable solids and reactive substances

Solids that ignite readily, materials liable to spontaneous combustion, and substances that emit flammable gas on contact with water.

Typically includes: Matches, sulphur, activated carbon, calcium carbide, some metal powders.

4.1Flammable solids, self-reactive substances, desensitised explosives
4.2Liable to spontaneous combustion
4.3Emit flammable gas on contact with water

Class 5 — Oxidising substances and organic peroxides

Materials that yield oxygen and so intensify a fire, and organic peroxides which are thermally unstable. Temperature control is often mandatory for the latter.

Typically includes: Ammonium nitrate, hydrogen peroxide, calcium hypochlorite.

5.1Oxidising substances
5.2Organic peroxides

Class 6 — Toxic and infectious substances

Substances liable to cause death or serious injury if swallowed, inhaled or absorbed, and materials known or reasonably expected to contain pathogens.

Typically includes: Pesticides, arsenic compounds, clinical and diagnostic specimens.

6.1Toxic substances
6.2Infectious substances

Class 7 — Radioactive material

Material with activity above defined limits. Carriage is governed by its own transport index and criticality controls in addition to the general dangerous-goods rules.

Typically includes: Medical isotopes, uranium compounds, certain industrial gauges.

Class 8 — Corrosives

Substances that destroy living tissue or, on leakage, materially damage other cargo or the vessel itself. Packaging compatibility is the recurring failure point.

Typically includes: Sulphuric acid, sodium hydroxide, batteries containing free acid.

Class 9 — Miscellaneous dangerous substances and articles

Hazards real enough to regulate but not fitting classes 1 to 8. In practice the class most shippers meet first, because lithium batteries and marine pollutants sit here.

Typically includes: Lithium-ion batteries, dry ice, asbestos, environmentally hazardous substances.

Questions

How many IMO dangerous goods classes are there?: Nine. Several are split into divisions — class 2 into flammable, non-flammable and toxic gases, for example — and the division usually decides the handling more than the class does.
Which class do lithium batteries fall under?: Class 9, miscellaneous. They are the reason many shippers meet dangerous goods rules for the first time, and the packing and state-of-charge requirements are strict.
Does the class alone decide whether a carrier will take the cargo?: No. Carrier acceptance policy, port and terminal restrictions, packing group and the specific UN number all sit on top of the class. A substance acceptable on one service may be refused on another.

A summary for orientation. The IMDG Code published by the International Maritime Organization is the governing text, and FrateZone is not affiliated with the IMO.

Provided for convenience and general information only.Figures, definitions and descriptions on these pages are compiled from publicly available sources — published industry standards, official code registers and carriers' own published specifications — and are nominal: actual equipment, regulations and commercial terms vary by manufacturer, carrier, jurisdiction and contract, and change over time. FrateZone is not the issuing authority for any of it, does not warrant that any figure here is correct, current or complete, and makes no representation that a source has not changed since it was read. Where a specification belongs to a specific physical unit or a specific contract — a container's certified plate, an airline's tariff, the wording of your own sale agreement — that document governs, not this page. FrateZone accepts no liability for any error or omission here, nor for any operational, commercial, financial or legal decision taken in reliance on it. Verify against the authoritative source before you act.

IMO dangerous goods classes