In the processes of Transporting of Dangerous Goods by Ground the proper classes must be displayed on the truck, and be documented in the paperwork associated with the shipment. The consignor of the shipment is responsible by law for determining the correct classification of the dangerous goods being transported, and the contents must be classified before the carrier takes possession.
Schedule 1 of the TDG Regulations asks that you indicate the type of hazard that is being transported. There are nine classes of dangerous goods, and each class has multiple subclasses dictating the subsidiary hazards to the main class.
For example: Class 1.3 (The 1 represents Explosive Hazards, and .3 represents the additional fire hazard risk that comes with this class)
Class 1: Explosives
1.1 Mass Explosion Hazards
1.2 Projection Hazard
1.3 Fire Hazard
1.4 Minor Hazard
1.5 Very Insensitive Explosion
1.6 Extremely Insensitive Explosives
Class 2: Gases
2.1 Flammable Gases
2.2 Non-Flamable Gases
2.3 Toxic Gases
Class 3: Flammable Liquids
Class 4: Flammable Solids
4.1 A solid that under normal conditions of transport is readily combustible, or would cause or contribute to fire through friction or from heat retained from manufacturing or processing, or is a self-reactive substance that is liable to undergo a strongly exothermic reaction, or is a desensitized explosive that is liable to explode if not diluted sufficiently to suppress their explosive properties.
4.2 A substance liable to spontaneous combustion, under normal conditions of transport, or when in contact with air, liable to spontaneous heating to the point where it ignites.
4.3 A substance that, on contact with water, emits dangerous quantities of flammable gases or becomes spontaneously combustible on contact with water or water vapour.
Class 5: Oxidizing Substances and Organic Peroxides
5.1 Oxidizing Substances
5.2 Organic Peroxides
Class 6: Toxic & Infectious Goods
6.1 Toxic Substances
Class 7: radioactive Substances
7.1 Lowest Radiation Level
7.2 Mid Radiation Level
Class 8: Corrosives
Class 9: Miscellaneous Products, Substances, or Organisms