Dangerous goods are substances, objects, solutions, mixtures, preparations, and wastes that present a risk to health, safety, goods, or the environment.
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Depending on the risk they pose, they are classified into different classes of dangerous goods. Further, they are assigned a four-digit number, the so-called UN-Number, or UN-ID, in order to classify them further.

The classes of dangerous goods are the following:

For example, UN 1350 would classify Sulfur, which belongs to Class 4: "Flammable Solids."

When shipping dangerous goods by sea, it is necessary not only to placard and mark every package but also to correctly placard the unit of transport, for example, the container.

Overview of Hazard Labels: