Segregation

Segregation is defined as "the process of separating two or more substances or articles which are considered mutually incompatible when their packing or stowage together may result in undue hazards in case of leakage, spillage, or any other incident." Segregation is achieved by maintaining certain distances between incompatible dangerous goods or by requiring steel bulkheads or decks between them. Spaces between two incompatible dangerous goods can be filled with other cargo compatible with the dangerous substances. Segregation terms likely to be encountered in this and other chapters of Part 7 include the following:

• "away from"
• "separated from"
• "separated by a complete compartment or hold from"
• "separated longitudinally by an intervening complete compartment or hold from"

These terms are specifically defined based on the type of ship on which they are being transported.

There are many possible combinations of dangerous substances, materials, and articles that require segregation. An overview of these possible combinations is given as a table at 7.2.4, and specific segregation codes are provided under 7.2.8. These codes, which are designated with the letters SG and a number, are used in DGL column 16b. For example, for UN 1791 HYPOCHLORITE SOLUTION, column 16b lists the segregation code SG20. Looking at the table of segregation codes, we find the statement "Stow 'away from' acids." A graphic flowchart, followed by several examples of its use, is provided after the segregation code table to aid in the process of deciding whether a given good must be segregated.

To learn more about IMDG visit our International Maritime Dangerous Goods Code Online Training web page.