Dangerous substances are materials (chemical agents) which due to their chemical, physical or biological properties, if handled improperly, can lead to death, damage to human health, body injury or financial losses. Dangerous materials are grouped in following classes based on their properties:
1 – Explosive materials and objects
2 – Gases
3 –Flammable liquids
4.1 – Solid flammable chemicals, self-activating agents and explosive desensibilized solid substances
4.2 – Spontaneously combustable substances
4.3 – Substances that in contact with water emit flammable gases
5.1 – Oxidizing substances keeping fire on
5.2 – Organic peroxide
6.1 – Toxic substances
6.2 – Infectious substances
7 – Radioactive materials
8 – Corrosive substances
9 – Miscellaneous dangerous goods
Dangerous goods are substances and goods, the transportation of which is prohibited under the ADR Convention or is permitted but only at the conditions set forth therein. In practice, this means that the transport of dangerous goods – due to the need to safeguard people and environment – is subject to separate regulation concerning permitting the carriage of particular substance, its classification, requirements for packaging, labeling as well as special requirements for the vehicle carrying the goods and the procedures involved in the transport.