Class 3 - Packing Group Criteria

Flammable liquids are assigned to Packing Groups I through III based on their flash point and boiling point.

• When the boiling point is less than or equal to 35°C (95°F), then the flammable liquid is assigned to Packing Group I.
• If the boiling point is greater than 35°C (95°F) and has a flash point less than 23°C (73.4°F), then the dangerous good is assigned to Packing Group II.
• If the boiling point is greater than 35°C (95°F) and has a flash point greater than or equal to 23°C (73.4°F) but less than or equal to 60°C (140°F), then the dangerous good is assigned to Packing Group III. These liquids are combustible.

If a liquid has an additional hazard other than flammability, then the assignment of a packing group must also take into consideration the packing group of the additional hazard.

Viscous flammable liquids, such as paints, varnishes, adhesives, and polishes, that have a flash point of less than 23°C (73.4°F) may be assigned to Packing Group III, provided that they meet the following criteria:

• The viscosity and flash point are in accordance with IATA DGL, Table 3.3.B.
• Less than 3% of the clear solvent layer separates in the solvent separation test.
• The mixture does not meet the criteria for Division 6.1 or Class 8.

Leakproof tests and internal pressure tests must be performed on all types of packaging intended to contain liquids.

To learn more about Multimodal Shipping visit our Multimodal DOT, IATA & IMDG HAZMAT Shipping Online Training web page.