Dangerous Goods in Holds on Non-Containerised General Cargo Ships
Segregation on a conventional cargo ship follows exact UN entries, hazards, DGL codes, segregation groups and Table 7.2.4; neither a generic class nor a CTU shell alone determines the required level.
Operational Explanation
Do not derive separated by a complete compartment or hold from mnemonic class families such as oxidizer versus flammable. Identify both goods and apply all entry-specific and mode-specific provisions. A container wall does not automatically equal the structural separation defined by the Code.
Regulatory Reference
IMDG Code (Amendment 42-24, res. MSC.556(108)): segregation table with the four categories of increasing separation, applicable both to containerised cargo and to non-containerised cargo in the hold; for non-containerised cargo, physically applying the segregation distances requires dedicated stowage planning, without the delimiting aid of a container.
IMDG 7.1 contains general stowage provisions; 7.2 covers general segregation, including table 7.2.4. For conventional stowage on general cargo ships also apply 7.6. For containers in permanently fitted positions check 7.4 instead. Do not assign all transport modes to chapter 7.1 alone. IMDG 2024, chapter 7.6.
SOLAS VII/5 requires loading, stowage and securing of packaged dangerous goods under the approved Cargo Securing Manual. Securing does not replace IMDG segregation. The SOLAS II-2/19 Document of Compliance, where required, concerns construction and equipment suitability: check permitted goods and spaces, including applicable exceptions.
Keep walkways, firefighting equipment and safety facilities accessible in the physical stowage plan. Check allowable loads, package condition, supports and securing; retain actual locations in the manifest or detailed plan and recheck after cargo changes. IMDG: chapter 7.6.
Scope of Application
Packaged dangerous goods on non-containerised/conventional general cargo ships, on deck or below deck, under DGL, packing and ship arrangement. Also check SOLAS II-2/19 Document of Compliance, approved CSM and SMS.
Procedure / How to Complete It
- Identify both goods by exact UN number and proper shipping name.
- Collect primary/subsidiary hazards, packing group and special provisions.
- Apply DGL stowage/segregation entries, segregation groups and Table 7.2.4.
- Apply provisions for conventional cargo ship, on deck/below deck and packaging type.
- Check the plan against SOLAS II-2/19 Document of Compliance, approved CSM, ship arrangement and SMS.
- If the result cannot be determined, do not load by mnemonic rule: obtain competent assessment.
Practical Example
For oxidizer and flammable goods no level is assigned in advance: compare exact UN entries, subsidiary risks, segregation groups and Table 7.2.4, then verify whether ship structure meets the resulting separation.
What Typically Goes Wrong
Using class names alone or presuming the container constitutes the required intervening complete compartment or hold.
Common Mistakes Mistake Library
| Mistake | Consequence | How to avoid it |
|---|---|---|
| Mode-specific stowage and segregation provisions not applied to conventional non-containerised cargo | Physically insufficient segregation distance in the hold | Use the exact UN entries, DGL codes, segregation groups, Table 7.2.4 and mode-specific provisions; do not treat a CTU shell as the required structural separation |
| Stowage compatibility checked only between dangerous substances, not against the conventional cargo present in the same hold | Incompatibility not detected with non-dangerous but still sensitive cargo (e.g. foodstuffs, heat-sensitive materials) | Always check stowage compatibility also against the conventional cargo present in the same hold |
| The more severe segregation categories (complete compartment, longitudinal separation) not planned structurally in advance | Inability to meet the required segregation with a stowage arrangement already planned | Plan the cargo plan structurally from the outset when more severe segregation categories are required |
What the PSCO Checks
Operational Tips
- Apply the provisions for the actual transport mode and ship arrangement; a container wall is not automatically an intervening complete compartment or hold.
- Plan the cargo plan structurally from the outset when more severe segregation categories are required.
- Always check stowage compatibility also against conventional non-dangerous cargo present in the same hold.
Preparation checklist
- Exact UN/PSN for both goods
- Primary/subsidiary risks and packing group
- DGL codes and segregation groups
- Table 7.2.4 applied
- On deck/below deck and ship type checked
- DOC/CSM/SMS and ship structure consistent
- No mnemonic rule used as final decision
FAQ
Related Topics
Last substantive revision of this page: 15 September 2026 · page fingerprint 7e9290ce443d