Dangerous Goods are articles or substances which are capable of posing a risk to health, safety, property or the environment and which are shown in the list of dangerous goods in the ICAO Technical Instructions, or which are classified according these Instructions.
Class 1 - Explosives, articles and substances are assigned to one of six divisions and to one of thirteen compatibility groups. Not all compatibility groups are to be found in all divisions.
Only explosives in Division 1.4, compatibility group S are permitted on passenger aircraft.
Only explosives in Division 1.3, compatibility groups C and G and Division 1.4, compatibility groups B, C, D, E, G and S are permitted on a cargo aircraft. (Approvals or Exemptions are often necessary).
Class 2 - Gases, compressed, liquefied, dissolved, refrigerated liquefied gases; mixtures of one or more gases with one or more vapours of substances of other classes; articles charged with a gas, and aerosols.
Class 3 - Flammable Liquids, includes the following substances:
Class 3 has no divisions, flammable liquids are assigned to packing groups according to the flash point and the boiling point of the liquid (ICAO Technical Instructions Table 2-4)
Class 4 - Flammable Solids; Substances Liable to Spontaneous Combustion; Substances which in Contact with Water, Emit Flammable Gases Three Divisions:
4.1 Flammable Solids; Self-reactive Substances; and Desensitized Explosives:
4.2 Substances Liable to Spontaneous Combustion (RSC) - are liable to spontaneous heating under normal conditions encountered in transport, or to heating up in contact with air, and being then liable to catch fire, e.g. Phosphorus white and yellow
4.3 Substances which, in Contact with Water, Emit Flammable Gases (RFW) - Substances, which, by interaction with water, are liable to become spontaneously flammable or to give off flammable gases in dangerous quantities, e.g. Sodium, Potassium
Class 5 - Oxidizing Substances and Organic Peroxides
Class 6 - Toxic and Infectious Substances
lass 7 - Radioactive Material (RRW, RRY) means any material containing radionuclides where both the activity concentration and the total activity in the consignment exceed the values specified in Table 2-12 of the ICAO Technical Instructions.
Radioactive material must be assigned to one of the proper shipping names/UN numbers specified in Table 2-11 of the ICAO Technical Instructions, depending on the activity level of the radionuclides, the type of package to be presented for transport, and the nature or form of the contents of the package, or special arrangements governing the transport operation.
Class 8 - Corrosives (RCM) - Substances which by chemical action, can cause severe damage when in contact with living tissue or, in the case of leakage will materially damage or even destroy, other goods or the means of transport, e.g. acids, Benzotrichloride
Class 8 has no divisions; the packing group must be assigned based on corrosivity (ICAO Technical Instructions Part 2; 8.2.5).
Class 9 - Miscellaneous Dangerous Goods (RMD) - Articles and substances, which during air transport, present a danger not covered by other classes, e.g. engines (internal combustion), vehicles, consumer commodity, dry ice, magnetized material.