What are the risk and consequences of improper loading?
What are the risks and consequences of improper loading?
In many cases, packers often overlook essential container loading principles.
During numerous claims assessments, we have frequently observed incidents of container tipping during road transport, following the uncoupling of a semi-trailer, or during handling operations.
Examples from our assessments include:
- A container tipped over after being uncoupled at a logistics facility, directly due to the improper reel loading plan.
- A container carrying dangerous goods tipped over when the trailer was uncoupled; 87% of the cargo’s mass had been loaded into just 50% of the container’s length.
- A container tipped onto the road while moving in a straight line at low speed. Fortunately, there were no injuries, but both the cargo and the container sustained significant damage.
These incidents could have been prevented if the packers/loaders had followed basic weight distribution principles for containers.
Without this fundamental knowledge, loaders often place the heaviest and tallest loads at the front, finishing with lighter items. When containers are not fully loaded, gaps often remain near the doors.
A “staircase” loading method is also commonly used, especially for non-palletized loads. While placing the heaviest items at the front might seem logical for stability during sudden braking in road transport, it does not ensure proper weight distribution throughout the container.
Furthermore, although the front wall should face the direction of travel, a container can be loaded from either end. Proper attention to loading techniques is essential to avoid these issues.
What are the laoding regulations for containers?
IMDG Code (Stuffing Certificate)
As stated in Chapter 5.4.2.1, the packer is responsible for properly loading the goods. By signing the stuffing certificate, the packer confirms that the cargo’s mass has been correctly distributed within the container.
For more detailed guidelines, the IMDG Code directs readers to the CTU Code, which outlines cargo securing requirements “as set out in the CTU Code.”
Examples include:
- Non-active carbon blacks of mineral origin.
- Shipments of coal that have passed the spontaneous heating test, as specified in the Manual of Tests and Criteria (see 33.4.3.3). These shipments must be accompanied by a certificate from a laboratory recognized by the competent authority, verifying that trained personnel correctly sampled the product and that the test was conducted properly and successfully.
- Steam-activated coals.
Load distribution according to CTU (3)
Chapter 3 outlines the general requirements, including guidelines on planning (Section 3.2):
“Create a loading plan when necessary.
Ensure the permissible payload of the equipment is not exceeded.”
It also addresses loading rules (Section 3.3):
“Distribute heavy cargo evenly across the floor surface.
Position the cargo to ensure the center of gravity is properly aligned within the transport vehicle.”
Loading responsibilities in the CTU Code – 4.2.
In the chapter on the chain of responsibility and information, the following points are highlighted:
“The packer is responsible for ensuring that the cargo is properly distributed within the transport vehicle and adequately secured when necessary.”
Given this, it is clear that the responsibility lies with the packer. Therefore, the planning stage of the loading plan is crucial and should never be overlooked. However, it must be noted that this preliminary assessment is often neglected
Loading Regulations for Containers
IMDG Code (International Maritime Dangerous Goods Code) and CTU Code (Code of Practice for Packing of Cargo Transport Units) provide guidelines for loading containers. According to Chapter 5.4.2.1 of the IMDG Code, packers must load goods appropriately. By signing the stuffing certificate, the packer certifies that the cargo mass has been properly distributed.
What are the principles of container loading?
Appendix 7 of the CTU Code (Loading and Securing in Transport Equipment) outlines key guidelines for ensuring proper weight distribution within containers:
“Containers, including platform containers and flatbeds, are constructed according to ISO standards to safely carry the permissible payload (P) when it is evenly distributed across the loading surface. This design allows the load to be supported by the four corner posts under all transport conditions. If the load is not evenly distributed, special considerations for concentrated loads must be applied.
When containers are handled horizontally during transport, the cargo should be arranged and secured so that its center of gravity is as close as possible to the middle of the container’s length and width. Ideally, the center of gravity should not deviate by more than ±5%. A practical rule of thumb is to distribute 60% of the cargo’s total mass over 50% of the container’s length. In some cases, a deviation of up to ±10% can be tolerated, as modern container handling equipment can accommodate slight offsets.”
In essence, the load’s center of gravity should be positioned near the container’s midpoint, with a small margin for adjustment as described.
Despite these guidelines, cases of tipping often reveal that the center of gravity was significantly outside the acceptable range. Unfortunately, improper weight distribution continues to be a common issue during our frequent inspections at various packing sites.
What are the steps and methods involved in loading a container correctly?
To ensure correct weight distribution, we recommend following a few essential steps.
Begin by confirming the maximum payload capacity of the transport vehicle or container to avoid overloading. The combined weight of the cargo must not surpass this limit.
The PAYLOAD is clearly indicated on the CSC plate and also on the right-hand door of the container. It reflects the maximum permissible gross weight, subtracting the tare weight of the equipment.
Method A
To ensure proper container loading, we recommend the following steps:
- Determine the weight of each handling unit by consulting packing lists, labels, or other relevant documentation.
- Count the number of handling units or pallets arranged on the floor.
- Rearrange loads where possible to maximize floor coverage, reducing empty spaces and simplifying the process of securing the cargo.
- Identify the heaviest items in the batch. If there are significant gaps, position these loads centrally or adjust the configuration for balanced weight distribution.
- Align the cargo to ensure it is centered evenly across the container’s width (both right and left sides).
- Utilize a loading plan, either in printed or digital format, to arrange handling units by zone according to the planned layout. Make sure to follow the CTU Code guideline, which suggests distributing 60% of the total cargo weight over 50% of the container’s length.
Method B
This method is more precise and involves documenting the exact placement of each handling unit within the loading area.
Appendix 4 of the CTU Code offers a straightforward calculation technique to determine the longitudinal position of the cargo’s center of gravity. Using the formula provided, you can calculate the distance ddd from the front of the container, but this requires knowing both the weight and position of each load.
While this method is generally too time-consuming and impractical for on-site use, it is valuable for detailed mass distribution planning when necessary. If the first method does not provide an accurate assessment due to the complexity of the load, this more advanced calculation becomes essential.
Experts often use this calculation during initial planning stages or when reviewing incidents to verify that the loading plan meets proper distribution standards.
Conclusion:
While we’ve outlined basic loading guidelines, we haven’t yet addressed handling concentrated loads, which require specific techniques.
Our on-site experience has repeatedly shown a significant lack of awareness regarding the correct distribution of weight within transport vehicles, particularly containers. Such issues can lead to serious risks and disruptions across the entire transport chain.
Once a container is sealed, inspecting its interior becomes impossible, making it difficult to address any loading errors. Often, these problems only come to light during transit or handling, by which time it is too late to take corrective action.
We recommend that loading facilities implement a strict, three-phase control system: thorough planning, careful execution, and vigilant supervision. It is also crucial for all involved parties to update or acquire the necessary expertise in proper loading practices.
For more detailed guidance, consider enrolling in our “CTU Code” training course.