Reducing Dry Ice Sublimation: Best Practices for Optimal Use with Insulated Containers

Dry Ice, the solid form of carbon dioxide (CO2), is widely used for cooling and shipping temperature-sensitive items. However, one challenge associated with Dry Ice is sublimation, the process by which it transitions directly from a solid to a gas.
Managing sublimation is critical to maximize efficiency and minimize waste. In this article, we’ll explore the science of Dry Ice sublimation, its rate, and effective strategies to reduce it using specialized containers like Dry Ice storage containers, Dry Ice shipping boxes, and durable insulated containers.
What Is the Science Behind Dry Ice Sublimation?
Dry ice sublimates because it is solid CO2 that exists at -78.5°C (-109.3°F) under normal atmospheric pressure. Unlike water ice, it does not melt into a liquid but transitions directly into CO2 gas. Sublimation occurs because of heat transfer from the surrounding environment to the Dry Ice. Factors that influence this process include:
- Temperature: Higher ambient temperatures accelerate sublimation.
- Surface Area: Increased surface area speeds up sublimation as more of the Dry Ice is exposed to heat.
- Air Movement: Greater air circulation around the Dry Ice enhances heat transfer and sublimation.
- Insulation: Poorly insulated containers allow more heat transfer, leading to faster sublimation.
What Is the Rate of Dry Ice Sublimation?

The sublimation rate of Dry Ice depends on storage conditions. On average, “…dry ice sublimates at a rate of 3% to 8% per day, depending on the thermal properties of the container and external temperature profile”, as mentioned on www.dryiceproduction.com/en/dry-ice.php.
Factors such as container type, ambient temperature, and air movement can significantly alter this rate. Proper storage can greatly reduce sublimation losses, preserving the cooling power of the Dry Ice.
It’s important to note that sublimation rates vary depending on the form of Dry Ice; the more surface area = the higher sublimation rate.
Common forms of Dry Ice:
- Large blocks or slabs
- Small cylindrical pellets or nuggets (usually 1/2″ or 5/8″ in diameter)
- Tiny rice, high surface to volume pellets (usually 1/8″ in diameter)
For example, slabs of Dry Ice tend to last longer than pelletized Dry Ice. In other words, pelletized dry ice may sublimate more quickly under the same conditions due to its increased surface area.
At the same time, it’s important to consider the size of the Dry Ice pellets will affect the density of dry ice in your container, ultimately affecting the weight of Dry Ice your container can hold. Weight is a critical factor if you are shipping.
How to Properly Use Dry Ice Containers to Reduce Sublimation
Choosing the right container and storage method is essential to minimize Dry Ice sublimation. Below are some key strategies:
1. Use Specialized Dry Ice Storage Containers
Dry ice storage containers are specifically designed to minimize heat transfer. Look for containers with the following features:
- Thick Insulation: High-quality urethane foam or vacuum-insulated panels reduce thermal conductivity.
- Airtight Seal: A tight-fitting lid limits airflow and prevents heat from entering the container.
- Durable Materials: Containers made from materials like polyethylene or polyurethane can effectively withstand the cold and reduce heat absorption.
2. Optimize Dry Ice Shipping Boxes
When shipping temperature-sensitive goods, dry ice shipping boxes play a critical role in reducing sublimation. Here’s how to use them effectively:
- Layer Dry Ice Properly: Place dry ice on top of the items being shipped. Cold air sinks, so this ensures optimal cooling. Ensure there is some space above dry ice however to ensure air circulation that is hugely beneficial to ensuring low sublimation.
- Pre-Chill the Box: Pre-cool the shipping box to reduce the temperature gradient and minimize initial sublimation.
- Minimize Empty Space: Fill any empty spaces in the box with insulating materials such as Kraft paper, or fill void space with additional Dry Ice (if weight isn’t a concern).
3. Invest in Quality Dry Ice Chests
Dry ice chests, similar to high-performance coolers, are excellent for storage. To maximize their effectiveness:
- Choose a Chest with Thick Walls: The thicker the insulation, the better it will retain cold temperatures.
- Limit Lid Openings: Every time the chest is opened, warm air enters, accelerating sublimation. Plan your usage to minimize the frequency of lid openings.
- Keep in a Cool Location: Store the Dry Ice chest in a shaded or air-conditioned environment to further reduce heat exposure.
Additional Tips to Reduce Dry Ice Sublimation
- Bundle Dry Ice Together: Grouping dry ice blocks reduces the exposed surface area, slowing sublimation.
- Avoid Direct Contact with Warm Surfaces: Place a layer of insulating material between the Dry Ice and any warm surfaces.
- Use Reflective Covers: Reflective materials can deflect radiant heat, reducing the rate of sublimation.
Conclusion
Understanding the science of Dry Ice sublimation and employing effective storage solutions can significantly extend its usability. Investing in high-quality Dry Ice storage containers, dry ice shipping boxes, and Dry Ice chests is essential for minimizing waste and maintaining efficiency. By following these guidelines, businesses and individuals can maximize the value of their Dry Ice, ensuring optimal performance for cooling and shipping applications.
ThermoSafe Dry Ice durable containers are a good solution to help meet these criteria. There are many sizes and options, check them out here https://www.thermosafe.com/products/durable-insulated-containers/dry-ice-and-industrial/