|Condensation can appear when storing in shipping containers and during the inclement months of the year this can become more of an issue. There are a number of contributory factors that create this problem. To understand this problem in greater detail well endeavour to explain. Used shipping containers may have moisture in the floors from previous uses, and even new builds if left shut for prolonged periods may produce some moisture inside.|
|The items you are storing may well contain moisture of some kind even a bed mattress has a moisture content. Other house hold items like dishwashers, clothing washing machines, fridges and freezers, even in winter or summer, will turn that moisture to vapour and as the temperature changes. Ultimately the result is that vapour will become water droplets that gather on the ceiling and start falling to the floor or on stored items. To help prevent this there are many views and suggestions about, but in reality the most successful method is the use of chemical dehumidifiers. These work very well as they either contain silica gel or desiccant clay depending on the product you buy. Shipping lines have always traditionally used gel packets within clothing containers and electrical goods transportation. However “dry poles” as they have become known do work well. The costs vary greatly but you should not pay any more than around £30.00 each. Our recommended supplier of these is http://www.itsbonedry.com a very good and environmentally safe product supplier. Manually insulating shipping containers with ply clad compressed foam works but it is costly to achieve.
Equally there is another product proven to be helpful in this area called “Graffo” this is like a spray on porridge type product which is water based. This seems a very strange way to eliminate moisture but it is very good. This insulates the roof internally keeping heat in and cold out. Please contact us if you wish to learn more about this method of moisture prevention.
Container moisture technical bulletin
When deciding whether a certain Shipping Container is suitable for transporting a certain cargo, it is vital for those involved to have sufficient knowledge about the anticipated climatic conditions in the Shipping Container. The three major factors which have a decisive impact upon the crypto climate (microclimate) in the Shipping Container are as follows : external climatic conditions, the type of Shipping Container and the cargo being transported.
1. Temperature conditions in the container:
The temperatures encountered in containers are primarily determined by heat exchange across the container walls. Good heat-transfer properties, especially through the steel walls, and the relatively large ratio of container surface area to container volume have a favourable impact in this respect. There are reflective materials available on the market to reduce heat transfer, although expensive.
In addition to solar radiation, external air temperatures, wind and precipitation also have an impact upon temperatures. Due to the wide variation in levels of solar radiation over a day, considerable temperature variation also occurs inside the container. This particularly applies to the air layers located directly beneath the container roof, as this is where the effects of solar radiation are at their strongest and thus where the greatest heat exchange occurs. On exposure to precipitation, such as rain, the container roof likewise cools more rapidly than, for example, the sidewalls, and the underside of the roof thus cools down most readily. Overheating of the air inside the container, i.e. heating to above the external air temperature may be considerable even under normal weather conditions. In contrast, the variations in temperature of the cargo inside the container are less marked.
2. Humidity conditions in the container:
Seawater or rain may penetrate damaged containers. This constitutes a considerable potential risk. If the container is packed in wet weather (snow, rain), additional moisture may get into the container. As always the visual inspection of Shipping Containers is crucial for the safe transit of goods. Refer to our section on Shipping Container inspection for useful pro-active information. Any of our members will be able to offer services relating to repairs and inspection along with CSC certification.