Containers are not entirely sealed spaces—especially near the doors, there are often small gaps where outside moisture can seep in. Additionally, moisture is hidden in the cargo itself, the packaging materials, pallets, and even the wooden floors of the container. Since ocean shipping involves long transit times and significant temperature fluctuations between day and night, this trapped moisture can evaporate, condense into liquid droplets, and fall onto the cargo, potentially causing damage.

A key point to note is that container wooden floors always contain some level of moisture, with the recommended limit being no more than 14%. However, in practice, the moisture content often exceeds this limit, sometimes reaching over 30%. Therefore, it’s crucial to avoid using recently cleaned, still-wet containers. It’s also essential to block the container’s ventilation holes properly during use. Furthermore, you should use moisture detectors to check the packaging of the cargo, aiming to keep the moisture content below 9%. Similarly, pallets and other wooden materials must be kept as dry as possible.

After completing these preliminary steps, it’s important to use container desiccants, which can absorb excess moisture inside the container. By doing so, you can effectively control the moisture levels within the container and prevent damage to the cargo.