Dangerous goods are articles of substances which are capable of posing a hazard to health,safety,property & the environment. They are divided into 9 classes. Some of these classes are subdivided into divisions.

Class 1: Explosives

Division 1.1: Substances and articles that have a mass explosion hazard

Division 1.2: Substances and articles that have a projection hazard but not a mass explosion hazard

• Division 1.3: Substances and articles that have a fire hazard and either a minor blast hazard or a minor projection hazard or both, but not a mass explosion hazard

Division 1.4: Substances and articles that present no significant hazard

Division 1.5: Very insensitive substances that have a mass explosion hazard

• Division 1.6: Extremely insensitive articles that do not have a mass explosion hazard

Class 2: Gases

Division 2.1: Flammable gases

Division 2.2: Non-flammable, non-toxic gases

Division 2.3: Toxic gases

Class 3: Flammable liquids

Class 4: Flammable solids; substances liable to spontaneous combustion; substances which, on contact with water, emit flammable gases

Division 4.1: Flammable solids, self-reactive substances and solid desensitised explosives

Division 4.2: Substances liable to spontaneous combustion

Division 4.3: Substances that emit flammable gases when in contact with water

Class 5: Oxidizing substances and organic peroxides

Division 5.1: Oxidising substances

• Division 5.2: Organic peroxides

Class 6: Toxic and infectious substances

Division 6.1: Toxic substances

Division 6.2: Infectious substances

Class 7: Radioactive material

Class 8: Corrosive substances

Class 9: Miscellaneous dangerous substances and articles.

Some dangerous goods fall into one of 3 packing groups depending on the degree of danger they present to people and equipment:

• Packing group I: Substances presenting high danger

• Packing group II: Substances presenting medium danger

• Packing group III: Substances presenting low danger.