Substances, including mixtures and solutions, and articles are assigned to one of nine classes according to the hazard or the most predominant of the hazards they pose in transport. Some of the classes are divided into divisions. These classes and divisions are:
Class 4: Flammable solids; substances liable to spontaneous combustion;substances which, on contact with water, emit flammable gases
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Division 4.1: Flammable solids |
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Division 4.2: Substances liable to spontaneous combustion |
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Division 4.3: Substances which, on contact with water, emit flammable gases |
Class 5: Oxidizing substances and organic peroxides
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Division 5.1: Oxidizing substances |
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Division 5.2: Organic peroxides |
Class 6: Toxic and infectious substances
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Division 6.1: Toxic substances |
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Division 6.2: Infectious substances |
Remarks: The numerical order of the classes and divisions is not that of the degree of danger.
