ADR is the European Agreement concerning the International Carriage of Dangerous Goods by Road. (ADR stands for Accord Européen relatif au transport international des marchandises Dangereuses par Route). ADR includes a special procedure in road traffic related packaging, cargo insurance and labeling of dangerous goods.
Class 1: Explosive substances and objects used to perform explosions and pyrotechnics.
Class 2: gas or liquid
Class 3: Flammable liquids
Class 4: Flammable solids
Class 5: Oxidizing substances
Class 6: Poisonous (toxic) and infectious substances
Class 7: Radioactive substances
Class 8: Corrosives
Class 9: Mixed hazardous substances