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When dangerous goods are loaded in conventional way on general cargo ships the segregation rules are different from those applicable on container ships fitted for the permanent stowage of containers.

Segregation terms used in IMDG Code are same for all types of ships but application differs.

1. “away from”;
2. “separated from”;
3. “separated by a complete compartment or hold from”;
4. “separated longitudinally by an intervening complete compartment or hold from”

On general cargo ships there are different types of cargo loads which need different types of segregation.

• A) Segregation of packages containing dangerous goods and stowed in the conventional way
• B) Segregation of dangerous goods stowed in the conventional way from dangerous goods packed in containers
• C) Segregation of dangerous goods in containers stowed in conventional cargo spaces
• D) Segregation of dangerous goods in packaged form and solid bulk cargoes.

A) Segregation of packages containing dangerous goods and stowed in the conventional way

1. Away from:

Effectively segregated so that the incompatible goods cannot interact dangerously in the event of an accident but may be transported in the same compartment or hold or on deck, provided a minimum horizontal separation of 3 m, projected vertically, is obtained.

2. Separated from:

In different compartments or holds when stowed under deck. Provided the intervening deck is resistant to fire and liquid, a vertical separation, i.e. in different compartments, may be accepted as equivalent to this segregation. For on deck stowage, this segregation means a separation by a distance of at least 6 m horizontally.

3. Separated by a complete compartment or hold from:

Either a vertical or a horizontal separation. If the intervening decks are not resistant to fire and liquid, then only a longitudinal separation, i.e. by an intervening complete compartment or hold, is acceptable. For on deck stowage, this segregation means a separation by a distance of at least 12 m horizontally. The same distance has to be applied if one package is stowed on deck, and the other one in an upper compartment.

4. Separated longitudinally by an intervening complete
compartment or hold from:

Vertical separation alone does not meet this requirement. Between a package under deck and one on deck, a minimum
distance of 24 m, including a complete compartment, must be maintained longitudinally. For on deck stowage, this segregation means a separation by a distance of at least 24 m longitudinally.

B) Segregation of dangerous goods stowed in the conventional way from dangerous goods packed in containers

Dangerous goods stowed in conventional way must be segregated from containers packed with dangerous goods as as per Segregation of packages containing dangerous goods and stowed in the conventional way

For “away from” no segregation required between packages and container as per Segregation of packages containing dangerous goods and stowed in the conventional way

For “separated from” segregation between packages and containers must as for “away from” as per Segregation of packages containing dangerous goods and stowed in the conventional way

C) Segregation of dangerous goods in containers stowed in conventional cargo spaces

Different containers packed with dangerous goods when loaded in cargo holds not fitted with permanent stowage of containers must be segregated as per Segregation of packages containing dangerous goods and stowed in the conventional way

For “away from” no segregation required between packages and container as per Segregation of packages containing dangerous goods and stowed in the conventional way

For “separated from” segregation between packages and containers must as for “away from” as per Segregation of packages containing dangerous goods and stowed in the conventional way

D) Segregation of dangerous goods in packaged form and solid bulk cargoes

Notes

• 1 – “away from”
• 2 – “separated from”
• 3 – “separated by a complete compartment or hold from”
• 4 – “separated longitudinally by an intervening complete compartment or hold from”
• X – the segregation, if any, is shown in the Dangerous Goods List column 16b of IMDG Code or the individual entries in the IMSBC Code

Refer IMDG Code part 7, chapter 7.6 for more details.