Desiccants are made from:

• Silica gel (porous and moisture-absorbing but lower capacity).
• Calcium chloride (high-absorption, commonly used for industrial shipments).
• Montmorillonite clay (natural, lower-cost, but limited efficiency).
• Molecular sieves (used for specialized applications requiring ultra-low humidity levels).

Vdry Desiccant Bags primarily use calcium chloride for superior moisture protection.

It is important to consider the risk factors of your shipment and the requirements of your cargo to make the right container desiccant decision. 

In some cases high-absorption desiccant packs are the way to go, but in other scenarios a more economical model can be an appropriate option.

Several hard-to-control risk factors contribute to container rain and increase the likelihood of moisture damage inside a shipping container:

• Cargo -The moisture content of your goods contributes to the condensation cycle in the container. 
• Temperature -Not only is it impossible to control the weather, but your goods are exposed to conditions that are more extreme than those outside the container.
• Loading conditions -Loading cargo at a location where there is a higher volume of moisture in the air will see a greater relative humidity inside the container. Thus increasing the risk of container rain. 
• Position of container on vessel- If your container is exposed to direct sunlight then it will experience a greater range of temperature fluctuations, which influences the risk of container rain.
• Delays at loading/unloading -The most drastic temperature fluctuations occur at loading and unloading, as this is when the containers are directly exposed to the elements. Any delays at this stage of the voyage mean extending the period of heightened risk. 

Destination -If your shipment crosses the equator, or moves from one climatic zone to another, the risk of condensation damage will increase. The length of the voyage will also impact on the risk to your cargo.

When you load a shipping container it is full of moisture. This can be found in the air, the cargo, packaging, pallets and wooden flooring. 

As the temperature in the container increases this moisture evaporates into the air, increasing the relative humidity within.

When the temperature falls, this moisture condenses on the cooler surfaces of the container ceiling and walls.

This process of evaporation and condensation inside the container follows the repeated temperature changes between day and night, and is exacerbated by voyages across di erent climatic regions.

The result is container rain, which is when drops of condensation fall on the goods below. This leads to expensive cargo losses.

There are many different container desiccants available on the market, but not all are created equal.

One of the key factors when differentiating desiccants is the absorption capacity, which is based upon the gel mix used in manufacturing.

Because of this shippers opt for calcium chloride desiccants which can absorb up to 300% of their own weight. This is much greater than silica gel which has a capacity of around 40%.

Keep an eye out for models that claim to be calcium chloride-based, but contain very little calcium chloride, as this will lower the absorption capacity.

Think of this as comparing whiskey and beer. Both are alcoholic drinks, but drinking a pint of whiskey will leave you feeling different to how you would have done if you’d stuck with the beer.

A lot of container desiccant suppliers claim that theirs is the best on the market, without anything to back it up.

This is why it is important to make sure that when you’re assessing container desiccant options, that you ask the supplier for quality reports from an independent organization. 

These will help you compare desiccants in standardized conditions via a neutral party.

You need to pay attention to key characteristics such as absorption, leak resistance, material quality and non toxicity, and make sure these independently certified.

How much humidity a container desiccant will absorb during a shipment depends on a variety of factors. The main variable is the conditions inside the shipping container during the voyage. In conditions of higher humidity, your desiccant pack will absorb more. In lower humidity scenarios, the container desiccant will absorb less. The bottom line is that your humidity desiccant will absorb as much as is necessary to protect your cargo.

If you want a better idea of how your desiccant will perform, ask your supplier for a quality report in which the absorption is tested in standardized conditions.

The short answer is no. 

Using low cost desiccants means that you need a greater volume of material to achieve the same level of protection as you would with a lower quantity of high-absorption desiccants.

This means greater costs in material spending, as well as the costs in handling, shipping and storage.

Then you need to analyze the cost of increased of cargo damages when using lower cost container desiccants.

As we have already seen there are a variety of unpredictable factors that influence the risk of moisture damage to your cargo. So you should always consider variables such as the voyage length and the nature of your cargo.

Then you need to factor in the absorption capacity of the desiccant bag you are using. Packing your container with 10kg of silica desiccants will give you less protection than 10kg of calcium chloride desiccants.

Conversely, 2kg of calcium chloride desiccants will give you more absorption than 10kg of silica gel desiccants.

Understanding this is not only crucial to protecting your cargo, but also in avoiding overspending on unnecessary desiccant material.

The lifespan of desiccant packs depends on factors like container conditions, humidity levels, and the product’s absorption capacity. On average:

• Vdry cargo moisture bags can last several weeks to months, depending on the journey’s duration and moisture levels.
• Regular inspection and replacement after extended use ensure optimal performance.

To maintain effectiveness, desiccants should be stored in:

• A dry, airtight container to prevent premature absorption.
• A cool, low-humidity environment.
• Original packaging until use to prevent early activation.

Improper storage can reduce absorption capacity before deployment.

Vdry Desiccant Bags are available through authorized distributors and directly from EPG Industries via our contact page.

For bulk orders or specific requirements:

• Fill out our contact form here to request a quote.

• Call our team to discuss your order +1 786 516 2232
  . 
• Find an authorized distributor in your region.