IMO Class

IMO Description
Class 1 Explosives
1.1 Substances and articles which have a mass explosion hazard.
1.2 Substances and articles which have a projection hazard but not a mass explosion hazard.
1.3 Substances and articles which have a fire hazard and either a minor blast hazard or a minor
projection hazard or both, but not a mass explosion hazard.
1.4 Substances and articles which present no significant hazard.
1.5 Very insensitive substances which have a mass explosion hazard.
1.6 Extremely insensitive articles which do not have a mass explosion hazard.
Class 2

Gases: Compressed, Liquefied or Dissolved under Pressure

2.1 Flammable gases
2.2 Non-Flammable gases
2.3 Toxic gases
Class 3

Flammable Liquids

Class 4

Flammable Solids or Substances

4.1 Flammable solids
4.2 Substances liable to spontaneous combustion
4.3 Substances which, in contact with water, emit flammable gases.
Class 5

Oxidizing Substances (agents) and Organic Peroxides

5.1 Oxidizing substances (agents) by yielding oxygen increase the risk and intensity of fire
5.2 Organic peroxides – most will burn rapidly and are sensitive to impact or friction
Class 6

Toxic and infectious Substances

6.1 Toxic substances
6.2 Infectious substances
Class 7

Radioactive Substances

Class 8

Corrosives

Class 9

Miscellaneous dangerous substances and articles *

MHB

Materials hazardous only in bulk **

   
  * Marine pollutants which are not of an otherwise dangerous nature are listed in class 9
 

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