Dangerous Goods Segregation Tables: IATA and IMDG Compatibility Rules

Dangerous Goods Segregation: IATA and IMDG Compatibility Rules

Improper segregation of incompatible dangerous goods is a leading cause of hazmat incidents. Both IATA and IMDG regulations specify detailed segregation requirements that prevent dangerous reactions between incompatible materials during hazmat transport.

Why Segregation Matters

When incompatible dangerous goods come into contact—through packaging failure, spillage, or fire—the results can be catastrophic. Oxidizers contacting flammable liquids intensify fires, acids reacting with cyanides release toxic gas, and water-reactive materials contacting corrosives can cause explosions.

IATA Segregation Requirements

IATA regulations prohibit loading certain hazard class combinations in the same unit load device or aircraft position. The DGR contains detailed tables showing which classes can share space and which must be kept apart. Airlines may impose stricter segregation than IATA minimums.

IMDG Segregation Categories

The IMDG Code defines four segregation levels: “Away from” (minimum 3 meters in the same hold), “Separated from” (different holds or compartments), “Separated by a complete compartment” (at least one empty hold between), and “Separated longitudinally by an intervening hold.” These apply to containerized cargo and break-bulk alike.

Reading the Segregation Table

The IMDG segregation table cross-references all nine hazard classes against each other, indicating the minimum required separation. Understanding this table is essential for anyone packing containers with multiple dangerous goods classifications.

Container Packing Segregation

Within a single container, segregation requirements may be met through physical separation, barrier systems, or simply not loading incompatible materials together. A logistics partner with hazmat certification ensures proper segregation at the container packing stage.

Consequences of Segregation Violations

Segregation violations discovered at ports or airports result in shipment holds, unpacking requirements, fines, and potential prosecution. In worst cases, improper segregation has caused container fires, toxic gas releases, and vessel damage requiring millions in remediation.