Many millions of tonnes of packaged DG are transported by sea every year. Most is quite safely received, handled and conveyed, but serious accidents can happen if the provisions of the IMDG (International Maritime Dangerous Goods) Code are not met.

The IMDG Code, based on standards first developed by the United Nations in 1956, is intended to ensure that carriage of DG can be conducted safely. It became mandatory on 1 January 2004, under the provisions of the SOLAS (Safety of Life at Sea) Convention. Compliance with the IMDG Code is, therefore, a requirement of law in the 182 country signatories to SOLAS. The need for mandatory status has been reinforced by an average of two major ship fires or explosions each year over the period 1997-2004 where DG shipments were involved.