Dangerous goods shipping is the most heavily regulated segment of international freight. The rules are precise, the penalties for non-compliance are severe, and the potential consequences of getting it wrong extend well beyond financial liability. If you ship chemicals, batteries, pressurized containers, flammable liquids, or any substance that poses a hazard in transport, understanding the compliance framework isn't optional.
What Qualifies as Dangerous Goods?
Dangerous goods (also called hazardous materials or HAZMAT) are substances or articles that pose a risk to health, safety, property, or the environment during transportation. International regulations classify dangerous goods into nine classes:
- Class 1: Explosives
- Class 2: Gases (flammable, non-flammable, toxic)
- Class 3: Flammable liquids
- Class 4: Flammable solids, self-reactive substances, pyrophoric substances
- Class 5: Oxidizing substances and organic peroxides
- Class 6: Toxic and infectious substances
- Class 7: Radioactive material
- Class 8: Corrosive substances
- Class 9: Miscellaneous dangerous substances (includes lithium batteries)
Each class has sub-categories with different packing groups (I, II, III) that reflect the degree of hazard. The specific requirements - packaging, labeling, documentation, quantity limits - vary by class, sub-class, and packing group.
IMDG vs IATA DGR: Ocean vs Air
Two separate regulatory regimes govern dangerous goods transport:
IMDG Code (International Maritime Dangerous Goods Code) governs ocean freight. Published by the IMO, it specifies packaging, labeling, stowage, and documentation requirements for dangerous goods on vessels. The IMDG Code is updated biennially.
IATA Dangerous Goods Regulations (DGR) governs air freight. Published annually by IATA, it is stricter than IMDG in many respects - particularly for quantity limits and packing requirements. Some substances that can be shipped by sea under IMDG are prohibited in air freight entirely.
Core Documentation Requirements
- Dangerous Goods Declaration: A completed and signed IMDG or IATA DGR declaration identifying the substance by UN number, proper shipping name, class, packing group, and quantity.
- Material Safety Data Sheet (MSDS/SDS): The product's safety data sheet, which the carrier may request to verify classification.
- Package markings and labels: All packages must bear the appropriate UN number, proper shipping name, hazard class label, and handling marks.
- Emergency contact: A 24-hour emergency response contact must be provided for many dangerous goods classes.
Carrier Acceptance and HAZMAT Restrictions
Not every carrier accepts every dangerous goods class. Some classes are prohibited on specific vessel types; some are outright banned by certain airlines. TMG's carrier relationships include HAZMAT-approved carriers for each dangerous goods class, ensuring your cargo is booked on a carrier legally permitted and operationally equipped to carry it.
How TMG Handles Dangerous Goods
TMG's HAZMAT team includes certified dangerous goods specialists trained under IMDG and IATA DGR regulations. We verify classification against the current regulatory edition, prepare compliant documentation, coordinate appropriate carrier selection, and ensure all labeling requirements are met before cargo is tendered to the carrier. For new clients with dangerous goods requirements, we begin with a cargo classification review to confirm UN numbers, packing groups, and applicable regulations before the first shipment moves.