Hazard Classifications – ADR Classes Explained
Dangerous goods have to be classified in accordance with the requirements in ADR and assigned a UN number, name, description and packing group (where appropriate) as indicated in the Dangerous Goods list in ADR. They are therefore assigned to different classes dependent on their predominant hazard as follows:
- Class 1 – Explosive substances and articles
- Class 2 – Gases
- Class 3 – Flammable liquids
- Class 4.1 – Flammable Solids, self reactive substances and solid desensitized explosives
- Class 4.2 – Substances liable to spontaneous combustion
- Class 4.3 – Substances which, in contact with water, emit flammable gases
- Class 5.1 – Oxidizing substances
- Class 5.2 – Organic peroxides
- Class 6.1 – Toxic substances
- Class 6.2 – Infectious substances
- Class 7 – Radioactive substances
- Class 8 – Corrosive substances
- Class 9 – Miscellaneous dangerous substances and articles
Please also note that for packing purposes, certain substances are assigned a packing group.