Well-ventilated containers protect goods

Most goods shipped around the world are transported in containers. There are many different types and sizes of cargo transport units, but they all have one thing in common; the container must be in sound condition and properly vented.

Well-ventilated containers are important for the protection of goods during transport. Unfortunately, it has come to the attention of experts at If Insurance that several container shipping lines around the world deliberately deviate from UCIRC/Cargo Worthy guidelines by not providing compensation for the removal of taped ventilators during container controls in agreement with various ports.

Transporting goods in containers is often regarded as being parallel to transporting goods under deck. Therefore, it is important that the condition of the cargo transport unit (CTU) reflects this fact. Goods should be as safe in a container as they are under deck in the cargo hold. Also, sufficient ventilation and dehumidifiers should always be used when transporting moisture-sensitive cargo, especially when exposed to large temperature differences during transport.

Finally, containers used in international transport must have a valid safety approval plate, i.e., a CSC plate, which is the abbreviation for the Container Safety Convention.

Getting the basics right

When preparing goods for transport, it is important to inspect the outside of the container for any holes or cracks in the walls or roof. Also, make sure that the doors and the closing devices operate properly.

When possible, a visual inspection of the underside of the container will help detect if any significant corrosion problems exist with the door sills, the bottom side rails, cross members and e.g., bottom end rails. There should also be no markings or labels from the previous cargo, e.g., IMO placards. Be sure to follow any additional guidelines and recommendations when preparing goods for transport in a CTU.

container being inspected.

Inside the container, make sure that the doors close tightly, inspect the interior to uncover any incoming light through cracks, holes, door gaskets or otherwise. The container interior should also be dry, and the ventilation flowing freely as intended with vents unblocked and functioning properly. Make sure that the floor is smooth and clean, and no nails or other protrusions exist. In addition, the doors and walls must not have anything on them which could damage the cargo. Generally, the container should be clean, free of cargo residues and neutral in odour.

Keep in mind that if a container is damaged or not cleaned and thus not suitable for transporting your goods, you should reject it and demand a replacement unit.

Packing and loading goods

Inspections during packing and loading will help to ensure your goods will reach their destination safely. Check that the container is packed and loaded, and the cargo lashed appropriately for the anticipated transit stresses, i.e., longitudinal, lateral, and vertical. When securing the goods inside the container, keep in mind the restrictions of the structures and lashing points in the CTU. A lashing configuration is only as strong as its weakest link.

Please note, it is of the utmost importance that the goods are secured sufficiently by the doors so that nothing can fall out from the container when the doors are being opened. Falling goods are a serious threat that can result in bodily injuries, and even death, as well as cargo damage.

When necessary, make sure that enough dehumidifiers are placed inside the container. Finally, check that the doors have been properly closed. Utilise strong steel wire cables, padlocks, or high security seals to provide good protection from cargo theft.

Keep in mind that if a container is damaged or not cleaned and thus not suitable for transporting your goods, you should reject it and demand a replacement unit.

Moisture in containers

Condensation occurs when warm moist air hits a sufficiently cold surface. At each temperature, air can only retain a certain maximum amount of water vapour. The higher the temperature of the air, the more water vapour the air can carry. Thus, when hot “unsaturated” air hits a cold surface, and reaches the temperature where the air becomes saturated, the so-called dew point, the air must let go of the water it cannot carry. This leads to condensation forming on the surface.

Large temperature changes inside the container during sea voyages can also cause condensation. As an example, we can follow the journey of a container from the Nordics to Asia. A container is loaded with moisture-sensitive goods in Sweden during the winter. The CTU is transported at the top of the deck of a container ship bound for Asia. The goods are cold on departure, and during transport the container is exposed to strong tropical sunlight and heat from the Suez to the north of Singapore during the day.

At night, the temperature drops and tropical rain and/or flooding occurs on this container, in short: large temperature changes occur inside the container even in tropical climates. If the container/ship is bound for northern China, the temperature will drop once more. As a result, there will be a lot of moisture in this container when it arrives, especially if the ventilators have been taped over or blocked.

In effect, large temperature variations create condensation. When cold cargo meets hot temperatures, compounded with bad ventilation and with no dehumidifiers inside the container, there will be condensation in the container.

Within Cargo and Marine risks, at If Insurance, we are committed to helping you improve your cargo loss prevention capabilities and helping to prevent accidents and incidents which result in losses. Don’t hesitate to contact If Cargo Risk Specialists or Underwriters for more information.

two containers.
If the container is loaded on deck (outdoors) in warm tropical climates and exposed to direct sunlight during the day, it gets very hot inside the container. At night the temperature drops and may even occasionally be exposed to cooling such as rain or seawater spray.

Meet the expert

Rikard Sahl photo.

Rikard Sahl

Cargo Risk Specialist


Written by

Rikard Sahl and Kristian Orispää