CTU Code: Packing and Stowage of Cargo Transport Units
The IMO/ILO/UNECE Code of Practice for the packing of Cargo Transport Units provides practical guidance for filling, stowing and securing cargo inside containers and other transport units, with particular attention to dangerous goods.
Operational Explanation
The CTU Code (Code of Practice for Packing of Cargo Transport Units) was developed jointly by IMO, ILO and UNECE to provide practical guidance to anyone filling or stowing cargo in a Cargo Transport Unit (container, tank, vehicle), including procedures for dangerous goods. Unlike the IMDG Code, which governs classification and labelling, the CTU Code focuses on the operational practice of packing and securing cargo inside the transport unit.
The supporting informative material (MSC.1/Circ.1498) provides further practical and background guidance on applying the Code.
Regulatory Reference
The CTU Code (2014, developed by IMO/ILO/UNECE) is not mandatory in itself but is referenced as a good-practice reference by the IMDG Code for the packing of transport units; MSC.1/Circ.1498 provides complementary informative material.
Scope of Application
Anyone involved in filling, stowing and securing cargo inside containers or other CTUs, including terminal personnel, shippers and the crew members who receive and check the units before loading.
Procedure / How to Complete It
- Check the structural suitability of the CTU (integrity, weathertightness, absence of damage) before filling it.
- Apply the segregation and compatibility rules between different goods inside the same unit, in accordance with the IMDG Code.
- Stow liquid dangerous goods below solid ones where possible, and secure the cargo against movement during transport.
- Check that the external labelling of the CTU (placarding) is consistent with the declared contents.
- Check the weight distribution inside the CTU to avoid instability or localised overloading.
Practical Example
Example: a container with packages of dangerous goods of different but compatible classes is filled according to the IMDG segregation tables, with liquids positioned below solids and the cargo secured with nets and straps to prevent movement at sea.
Real Cases
Common Mistakes Mistake Library
| Mistake | Consequence | How to avoid it |
|---|---|---|
| CTU filled without a prior check of the structural integrity of the unit | Risk of loss of tightness or structural failure during transport | Always inspect the CTU before filling it, even when supplied by a third party |
| Liquid dangerous goods stowed above solid goods in the same unit | Risk of contamination or damage in the event of a leak | Always apply the liquids-below-solids stowage rule set out in the CTU Code |
| External placarding of the CTU not updated after changes to the contents | Misleading information for terminal personnel and emergency responders | Check the consistency between external placarding and actual contents before final closure |
PSC Observations
Operational Tips
- Do not rely solely on the shipper's documentation: a visual inspection of the CTU before loading remains the most effective defence against non-compliant packing.
- Consult the MSC.1/Circ.1498 informative material for practical examples of applying the CTU Code, useful for crew training.
- Pay particular attention to weight distribution: an unbalanced CTU is a risk even if the contents are correctly classified.
Checklist
- Structural integrity of the CTU checked before filling
- Segregation and compatibility rules applied inside the unit
- Liquids stowed below solids where possible
- External placarding consistent with the declared contents
- Weight distribution checked to avoid instability