Storing Dry Ice

What is dry ice and why is correct storage so important?

Dry ice is the solid form of carbon dioxide (CO₂) — the very gas we know from the air we breathe, carbonated drinks or fire extinguishers. At a pressure of around 5.2 bar and a temperature below -78.5 °C, CO₂ is liquefied and then expanded so that it solidifies abruptly. The result is dry ice: a whitish-grey solid available as a block, nugget or pellet.

Dry ice does not turn liquid when it warms up. Instead, it sublimates — meaning it goes directly from a solid to a gaseous state. No water is produced in the process, which makes it ideal for applications where moisture is unwanted.

Dry ice is used across countless fields — from industrial dry ice cleaning to cooling food and pharmaceuticals, all the way to atmospheric fog effects in film and theatre. Thanks to its extreme cold, it can also be used for localised freezing treatments or the temperature-stable shipment of sensitive goods.

Dry ice is a powerful and versatile refrigerant — but a volatile one. And that is precisely why it is so important to know how to store dry ice correctly so that you can use it safely and efficiently.

How long does dry ice last?

The shelf life of dry ice depends strongly on how it is stored. Depending on ambient temperature, humidity, container and quantity, dry ice evaporates at different rates during storage.

As a rough guide:

Important: the smaller the surface area per unit of mass, the slower dry ice sublimates. Large blocks last longer than pellets or nuggets.

Storing dry ice — how to do it right

To get the longest possible use out of your dry ice, the right storage technique is key. Here are the most important tips for storing dry ice correctly:

1. Use suitable insulated containers

Thermal containers made of expanded polystyrene (EPS) or special dry ice boxes made of polyethylene are best suited. These materials insulate excellently and prevent heat from penetrating from outside.

Make sure the container:

Wall thickness also plays a role: thick-walled containers offer better protection from heat. Anyone regularly using dry ice should therefore invest in professional transport and storage containers.

• is well insulated
• is kept dry and clean
• is not completely sealed

2. Cool — but not too cold

It sounds paradoxical, but dry ice should be kept cool, not deep-frozen. Storing it in a freezer compartment is pointless — there it is "too warm" (usually -18 °C), so it continues to sublimate. Even cold rooms at -30 °C cannot fully stop sublimation.

Ideal for storing dry ice is a temperature as constant as possible below 10 °C with low air circulation.

3. Do not store in enclosed rooms

CO₂ is an odourless gas that can be dangerous in high concentrations. Therefore, never store dry ice in closed, unventilated rooms — not even in a car or in small storage rooms without windows.

4. Reduce contact with air

The less contact with air, the slower the sublimation. Only open the insulated box when necessary. Large quantities of dry ice stored in a single container will keep more effectively than many smaller portions.

How does dry ice storage time vary in practice?

The storage time of dry ice depends not only on the container but also on a number of external factors:

Tip: plan your jobs so that the dry ice is used as soon as possible after delivery — especially at high outdoor temperatures.

• Transport route: long deliveries in summer temperatures significantly shorten the available usage time.
• Quantity: a larger block lasts longer than small pellets, since it has a smaller surface area per volume.
• Use: every removal brings warm air into the container — accelerating sublimation.

Storing dry ice — what you should avoid

So that you can store dry ice safely, here is an overview of the most common mistakes:

If you follow these points, you protect not only yourself but also others in your surroundings — especially when using dry ice blasting equipment in workshops or labs.

• Storing in the fridge or freezer: the temperatures are not low enough to prevent sublimation — and the CO₂ produced can damage electronic components.
• Sealing in airtight containers: sublimation produces gas pressure — in airtight containers this can lead to dangerous overpressure.
• Storing unlabelled: clearly label the storage container as "dry ice". This avoids confusion or improper handling by third parties.
• Touching without protective equipment: dry ice can cause severe cold burns. Always use insulated gloves or tongs when handling or portioning it.

Disposing of dry ice after storage — what to do with leftovers?

The good news first: dry ice leaves no residue, as it sublimates entirely into gaseous CO₂. Even so, when disposing of leftover quantities you should observe a few points:

Simply let it evaporate in a controlled way — and keep your distance while it does.

• Allow leftover dry ice to evaporate in a well-ventilated location in an open or partially open container — for example outdoors or in a hall with sufficient air exchange.
• Never dispose of dry ice down the drain, in the toilet or in household waste, as the sudden evaporation there can cause damage or burst pipes.
• Nor should it end up in waste containers or sealed containers — risk of explosion from pressure build-up!
• Avoid storing larger quantities for "spontaneous disposal" indoors at all costs. Even a few kilograms of dry ice can raise CO₂ concentrations in small rooms to dangerous levels.

Storing dry ice correctly — safely, efficiently and well organised!

Storing dry ice means handling a special material correctly. It is neither dangerous nor complicated — as long as you know what you are doing. The key factors for the shelf life of dry ice are above all a suitable insulated container, a well-ventilated room and proper handling during removal and transport.

As a manufacturer and supplier of dry ice, cleaning equipment and matching compressors for dry ice blasting devices, Dry Ice Energy knows the challenges of storing dry ice inside and out. Our experience shows: those who store dry ice smartly not only save on losses but can use it much more efficiently.

If you have questions about our product range or want to buy high-quality dry ice, feel free to contact us or our partners any time. We provide practical, solution-oriented advice — including on storing dry ice!