Storing dry ice: What to look out for?

How dry ice behaves during storage

Unlike conventional ice, dry ice does not melt but sublimates. This means it changes directly from a solid to a gaseous state. This process begins immediately after production and cannot be completely stopped, but it can be significantly slowed down if the right conditions are created. The better the dry ice is insulated and the more external heat is minimised, the lower the so-called sublimation rate and the longer the material remains usable.

Requirements for suitable storage containers

As carbon dioxide is released during sublimation, storage containers for dry ice must never be completely airtight. Otherwise, the resulting gas could create dangerous overpressure. Suitable containers are therefore specially insulated dry ice boxes or containers that protect the material from heat whilst allowing for the controlled release of gas. These containers are often made of highly insulating materials such as EPP or PE and are designed to maintain the internal temperature for as long as possible. Filling the container as completely as possible can help to reduce the loss rate, as there is less air inside that could promote the sublimation process.

Optimal storage conditions for a long shelf life

Dry ice should always be stored in a cool, dry place, away from direct sunlight or heat sources. A closed room without windows is ideal, as this minimises temperature fluctuations. Important: The room must still be well ventilated so that the CO₂ produced does not accumulate and there is no risk of suffocation. More on this in the next section.

The form of the dry ice also affects its shelf life. Large blocks sublimate more slowly than small pellets, as they have a relatively smaller surface area. The cooling capacity, e.g. for refrigerated transport, is maintained for all forms of dry ice even during prolonged storage. However, in dry ice blasting applications where small pellets are used, the quality of the blasting result may be compromised during prolonged storage. Therefore, dry ice that is as fresh as possible should be used for blasting.

Safety considerations when storing dry ice

As dry ice is extremely cold at a temperature of –78.5 °C, there is a risk of frostbite on direct skin contact. Protective measures such as wearing insulated gloves are therefore essential. Furthermore, the material should never be stored in airtight rooms, as the carbon dioxide gas produced can accumulate in enclosed spaces and, at high concentrations, the displacement of oxygen becomes a hazard. There is a particular risk of CO₂ build-up in small, unventilated rooms or vehicles, which is why it should always be stored in well-ventilated environments. Dry ice containers must not be stored in completely enclosed cars, as there is also a risk of suffocation in such situations.

How long can dry ice be stored?

The shelf life of dry ice varies depending on storage conditions and container type. In high-quality industrial boxes, a sublimation rate of just a few per cent per day is often achieved, whilst poorly insulated or open storage causes significantly higher losses. Anyone requiring dry ice for an extended period must therefore either receive regular replenishments or opt for an alternative that can meet their needs more flexibly.  

Storage options from ASCO – optimal solutions for all requirements

ASCO offers a wide range of specially developed storage solutions for the safe and efficient storage of dry ice. The insulated dry ice boxes and containers are designed to significantly reduce the sublimation rate, thereby ensuring a longer shelf life for the material. High-quality insulation materials such as EPP or PE keep the internal temperature as stable as possible, thereby minimising daily dry ice loss. The containers are available in various sizes – from compact boxes for smaller quantities to large-volume containers for industrial applications.

Another advantage lies in their practical handling: many models feature ergonomic lid systems, easy-to-clean interiors and robust construction, enabling safe transport within operational workflows. For mobile use, for example in logistics or catering, ASCO offers solutions that allow for easy integration into existing transport processes without compromising on efficiency and safety. Companies thus benefit from reliable storage technology that is tailored to varying volume requirements whilst helping to reduce losses.

Conclusion

The correct storage of dry ice is crucial for reliably utilising its cooling capacity and minimising losses due to sublimation. Those who understand the physical properties of dry ice, create suitable storage conditions and rely on high-quality container systems significantly increase efficiency in daily use. With ASCO’s specially developed dry ice boxes and containers, businesses gain practical solutions tailored to different storage requirements and ensuring maximum shelf life. This means that dry ice not only remains usable for longer but can also be utilised more economically – a decisive advantage for numerous industries and applications.