Transport of dangerous and marine pollutant substances by sea-transporting vessels is regulated by the Safety of the Life at Sea (SOLAS) and the International Convention for the Prevention of Pollution from Ships (MARPOL).

In the relevant sections of SOLAS and MARPOL, the International Maritime Dangerous Goods Code (IMDG) provides a detailed description of the necessary regulations and takes the provision of the law on the transport of these substances by sea. As of 1 January 2004, the IMDG Code was made compulsory.

For all types of transport (transport by sea, air, train, land and inland waterways), the classification and risk definition of dangerous goods is also made by the United Nations Committee of Experts on the Transport of Dangerous Goods (UN).

The dangerous goods classifications defined in these regulations are as follows: