Indeling van de gevarenklassen in groepen stoffen die tijdens het vervoer een gelijksoortig hoofdgevaar bezitten:
Class 1 Explosive substances and articles containing explosives

Class 1
Explosive Dangerous Goods: Explosive substances and articles used to produce explosions or pyrotechnic effect.
Class 1.1
Explosives with a mass explosion hazard
Class 1.2
Explosives with a severe projection hazard.
Class 1.3
Explosives with a fire, blast or projection hazard but not a mass explosion hazard.
Class 1.4
Explosives with a minor fire or projection hazard
Class 1.5
An insensitive substance with a mass explosion hazard.
Class 1.6
Extremely insensitive articles
Class 2 Gases

Class 2.1
Brandbare gassen.
Class 2.2
Verstikkende gassen.
Class 2.3
Giftige gassen.
Class 2.4
Oxiderenede gassen.
Class 3 Flammable liquids
Class 4 Combustable solids

Class 4.1
Brandbare vaste stoffen.

Class 4.2
ADR 4 zelfontbranding vatbare stoffen.

Class 4.3
ADR 4 stoffen die in contact met water brandbaar gas ontwikkelen.
Class 5 Oxidizer

Class 5
Oxiderende stoffen
Class 6 Toxic substances

Class 6
ADR 6 giftige stoffen.
Class 7 Radioactive components

Class 7
ADR 7 radioactieve stoffen
Class 8 Corrosive materials

Class 8
ADR 8 corrosive stoffen.
Class 9 Miscellaneous dangerous compounds

Class 9
ADR 9 diverse gevaarlijke stoffen.