Intermodal shipping containers spend the majority of their lives at sea. The sea has a high moisture content, which damages the container through an event called container rain.
This article will discuss container rain and ways to mitigate it.
What exactly is container rain?
The moisture present in the air is accountable for causing container rain. Loading and unloading of goods occurs near the ocean, where the air has more concentration of water in it. The moisture present in the air gets trapped in the container. Moisture condenses and becomes water in cooler sections of the container as the air in the container settles. When the container gets heated up again, the condensed water expands, lifts to the top of the container and gets attached to the walls and ceiling. This moisture on the walls is known as container sweat. It then drops down and is referred to as container rain.
What happens when the container rains?
When container rain drips into cargo, moisture-sensitive goods begin to grow mould. As a result, the other shipment gets permanently damaged or destroyed due to warping and corrosion. Around 10% of goods shipped using the sea routes get rejected because they get damaged due to the container rain. For the safe and secure freight transportation across the ocean, proper steps must be taken that can help reduce container rain.
Ways to mitigate the container rain
Moisture check
Always do a mandatory moisture check before loading your cargo into the vessel. Wipe off the moisture that is present in the container. This straightforward yet effective step can help save your shipment from the potential risk of moisture damage.
Ventilation
Improving the ventilation system of your container will help you equalize the temperature inside and outside of your container. It keeps the air temperature the same inside and outside the container. A highly efficient ventilation system will help to draw out the moist air from the container, thus keeping it moisture-free.
Choice of pallets
It would be best if you used plastic pallets instead of wooden pallets. Wooden pallets are known to absorb and hold moisture. Loading a cargo container near the ocean or in moist weather will expose the wood pallets to the ocean air, which has high moisture content. This will lead to extreme mould build-up in the shipping container during transit.
Insulation
An insulated container prevents extreme temperature differences. This will significantly reduce the build-up of moisture, thus keeping the risk of container rain at bay. Insulating your shipping container helps to control the temperature inside and prevents container condensation by distributing heat. It also helps to prevent mould, poor thermal efficiency, and limited air circulation.
Desiccants
Using desiccants is one of the most effective ways to ensure that the temperature inside the container is kept well within the dew point temperature. A desiccant is a hygroscopic substance used as a drying agent which could substantially reduce RH (relative humidity). They help to absorb the moisture in the air. They work by trapping the water in a gel, locking it in, and disallowing it to break out and return to the atmosphere at higher temperatures.
Dehumidifiers and air conditioning
It is one of the most costly and complex methods to prevent moisture from shipping containers. Dehumidifiers work as a great alternative when the container gets shipped for an incredibly long distance. The major problem with this method is the need for a regular power supply and the ability for the water to be emptied daily. A plumbing line can be installed outside to drain the ship, although this will incur additional costs.
Every year enterprises suffer massive losses due to their goods getting destroyed by the container rain. However, if measures like ventilation, desiccants, and insulation, are appropriately followed, they can effectively help to reduce the damages done by the container rain.
I hope you have understood everything about container rain and ways to mitigate it.