Class

Substances and goods subject to these regulation are assigned to one of 9 Classes detailed within the UN Model Regulations, determined by the predominant hazard of the substance or goods. Class 1 Goods and Substances are classified as Explosives, under the UN Explosive Hazard Classification System and Codes that is also outlined within the International Ammunition Technical Guideline (IATG).

Divisions

Class 1 goods are subdivided further into one of 6 distinct divisions, that describes the predominant explosive hazard that exists if that article was to detonate or activate while in transport or storage. These divisions are as follows:

• Class 1: Explosives
  • Division 1.1: Explosive that has a mass explosion hazard. A mass explosion is a detonation of almost entire load instantaneously.
  • Division 1.2: Goods and Substances without a mass explosion hazard, but with a projection (shrapnel/fragmentation).
  • Division 1.3: Goods and substances with a mass fire hazard, and a minor, blast and/or projection hazard, but without a mass explosion hazard
  • Division 1.4: Goods and substances with no significant explosive hazard. Explosive effect mostly contained by packaging. A fire must not cause a instantaneous mass explosion.
  • Division 1.5: Very insensitive goods and substances, with a mass explosion hazard (explosive considered so insensitive that initiation or transition from burning to detonation very unlikely under normal transport conditions).
  • Division 1.6: Extremely insensitive goods and substances without a mass explosion hazard (articles that contain predominantly extremely insensitive explosives, with negligible probability of accidental detonation, initiation, or propagation.

Explosive article are assigned a Class and a Division to determine a specific Hazard Division (HD) under this regulation, following a classification process and a number of tests. Under the UN Dangerous Goods classification, explosive hazard Divisions are awarded using the UN Manual of Criteria and Tests, by following the process flow chart '10.3 Procedure for assignment to a division of the class of explosives' and conducting the appropriate tests either UN series 5, series 6, or series 7 tests.^[3] Series 5 tests are used to determine if an article can be assigned to HD1.5 'Very Insensitive Explosive'; series 6 tests are used to determine the classification of an article within Hazard Divisions 1.1, 1.2, 1.3, or 1.4; and series 7 tests are used to determine if an article can be assigned to HD 1.6 as an article containing predominantly 'Extremely Insensitive Explosives'.

Compatibility Group

Generally speaking Dangerous Goods should not be transported together in the same container, this includes the shipment of different kinds of explosives, as the potential for an inadvertent detonation can increase dramatically if two highly incompatible explosives are transported together. To enable efficient transportation and storage, and , to allow the transportation of some explosives together, a further classification system is used called compatibility groups (CGs). Compatibility groups helps to group explosives of a similar type together, or allow the transportation of combinations that have been deemed safe. Hazard divisions and compatibility groups don't classify specific explosive compounds or substances, but rather a HD and CG classifies a specific article of explosive, including its packaging.

Compatibility groups further divide Class 1 explosives on the basis of the type explosive compound and risk of activation, or for CG 'S' the article's packaging, in order to determine which types of explosives are safe to transport with each other. Most explosives will be classified into groups, A, B, C, D, E, F and S. The other groups classify It is possible that two articles containing a number of the same explosive product (i.e. electric detonators) with different inner and outer packaging, could have Hazard Classifications of 1.2B and 1.4S, making one of the articles significantly safer to transport with other explosives.

Permitted Compatibility Mixing

In some cases it may be appropriate and safe to mix explosives when transporting or storing them, certain compatibility groups may be mixed with others and still remain safe.

X Denotes compatibility groups that can be mixed in transport.

Detonators/blasting caps, may not be packaged together with any other explosive.

a. Different explosives of compatibility group A should be packaged separately

b. Explosives of compatibility group L shall only be packed with an identical explosive.

c. Explosive articles of the compatibility group C, D, or E may be packed together, and the whole packaged shall be treated as belonging to compatibility group E.

d. Explosive articles of the compatibility group C and D may be packed together, and the whole packaged shall be treated as belonging to compatibility group D.

e. Explosive articles of the compatibility group C, D, E or N may be packed together, and the whole packaged shall be treated as belonging to compatibility group D.

f. Explosive belonging to the compatibility group G except for fireworks, may be packaged together with compatibility groups C, D, and E, provided they are not carried in the same compartment, carry box, or vehicle, and the whole packaged shall be treated as belonging to compatibility group E.

g. Explosive of compatibility group S, may be packaged together with explosives of any other group, except A or L, and the combined packaged may be treated as belonging to any of the compatibility groups most appropriate, except S.