Hazardous chemicals include:

1. Explosive articles: Explosive articles are articles containing one or more explosive substances or mixtures. It includes explosive substances, mixtures and explosive articles, but does not include devices that contain explosive substances or mixtures that, by virtue of their quantity or characteristics, will not act at the location of the device by accident or accidental ignition or by explosion, fire, smoke or loud noise after detonation.

2. Flammable aerosol: An aerosol is an aerosol spray can, which is a container that cannot be refilled. Containers are made of metal, glass or plastic and contain compressed, liquefied or dissolved gases with or without liquids, pastes or powders. It is equipped with a release device which ejects the contents to form solid or liquid particles suspended in a gas, or to form a foam, paste or powder, or in a liquid or gaseous state.

3. Self-reacting substances or mixtures: Self-reacting substances and mixtures are thermally unstable liquid or solid substances or mixtures that are prone to violent exothermic decomposition even in the absence of oxygen (air). The definition does not include substances and mixtures classified under the Uniform classification System as explosives, organic peroxides or oxides.

4. Pressurized gas: pressurized gas refers to the gas or liquefied gas or frozen liquefied gas loaded into the container at a pressure equal to or greater than 200kPa (pressure gauge). Pressurized gas includes compressed gas, liquefied gas, dissolved liquid and frozen liquefied gas.

5. Flammable solid: Flammable solid is a kind of solid that burns easily or can be ignited by friction or auxiliary combustion. Flammable solids are powdery, granular, or mushy substances that are very dangerous if able to ignite, and the flame can spread quickly after brief contact with burning matches and other ignition sources.