Whoever has opened a shipping container only to find his valuable cargo rusted, mouldy and dripping with water can readily appreciate the dangers of moisture in container transports.
There are several ways to ensure you minimize the amount of moisture in your shipping container;
Vents are a great way of keeping moisture out as they allow fresh air to pass through the container. Make sure your products are not touching the walls or ceiling of the container as this will reduce airflow. Another prevention when to try and do when having vents is keeping the doors closed on misty or wet days. This will allow moisture into the container that may not be able to fully leave the container.
You can get specific paint to cover your container in and this will reduce the amount of moisture in the container. The biggest down side to this method is the fact you have to open the doors of the container on a regular basis, which is not ideal if you are shipping a product long distance.