Dangerous Goods (IMDG Code)

Dangerous goods (hazardous materials, or hazmat, in US law) are substances and articles that can harm people, ships or the environment in transport: fuels, paints, solvents, gases, corrosives, many chemicals and lithium batteries among them. For sea transport the International Maritime Dangerous Goods (IMDG) Code, published by the IMO, sets the rules for packing, container traffic and stowage, "with particular reference to the segregation of incompatible substances". It has been mandatory under SOLAS chapter VII since January 1, 2004 and is amended on a two-year cycle.

The nine classes

The IMDG Code, the IATA rules and US regulations all use the UN classes: 1 explosives, 2 gases, 3 flammable liquids, 4 flammable solids, 5 oxidizers and organic peroxides, 6 toxic and infectious substances, 7 radioactive material, 8 corrosives and 9 miscellaneous dangerous goods (which includes lithium batteries). The US list of the same classes is at 49 CFR 173.2.

The shipper's job

• Classify the goods and find the UN number and proper shipping name, usually from the transport section of the safety data sheet
• Pack in UN-specification packaging suited to the class and packing group, and mark and label each package
• Declare: the dangerous goods declaration gives, in order, the UN number, proper shipping name, class and packing group, plus quantity (the same basic description US shipping papers need under 49 CFR 172.202)
• Book it as dangerous goods: the carrier must accept the class and UN number on that vessel and route, and the container is placarded and stowed under the segregation rules

US acceptance: 49 CFR 171.25

US hazmat rules allow a shipment moving by vessel to, from or within the United States, and its connecting truck or rail leg, to be offered and transported in accordance with the IMDG Code, provided the movement includes a vessel leg (49 CFR 171.25(a)). The truck or rail car must still be placarded under the US rules in 49 CFR part 172, subpart F.

LCL, FCL and air

• FCL is the usual route for dangerous goods, on carriers that accept the class on your lane
• LCL: many consolidations refuse dangerous goods, and the segregation rules decide what can share a container
• Air: the IATA Dangerous Goods Regulations apply, with a Shipper's Declaration for Dangerous Goods prepared by a trained shipper. Lithium-ion and lithium-metal batteries shipped on their own are forbidden as cargo on passenger aircraft and move cargo-aircraft-only; see air freight

Common mistakes

Undeclared hazardous cargo is the costly one: a fire or leak at sea puts the ship and every other shipper's cargo at risk. Declare anything with a safety data sheet at inquiry, and send the SDS with it, so the right carrier and container are booked. See hazardous cargo on FCL ocean freight.