1. What is a Dry Ice Pack?

A dry ice pack is a flexible sheet typically measuring 29 × 20 cm, 2 mm thick, and weighing about 40 grams. Once activated, each sheet weighs approximately 900 grams and shrinks to around 25 × 20 cm while expanding to about 3 cm thick.

The dry ice pack is made from a synthetic dehydrated gel and features two outer layers of perforated plastic and two inner layers of non‑woven textile. These layers encapsulate a post‑treated sodium polyacrylate copolymer. The packs can be activated when required, cut to size, remain flexible when frozen, and last up to seven times longer than ice.

2. How is a Dry Ice Pack Used and How is it Hydrated / Activated?

Dry ice packs are supplied in dehydrated form and only need to be soaked in water once for activation. After the sheet is fully hydrated, it can be reused repeatedly by simply freezing or heating.

To hydrate, immerse the sheet completely in warm water and gently scrunch it for around 15 minutes. The cells will visibly expand; when they stop expanding, the pack is ready for use.

3. When is the Dry Ice Pack Ready to Freeze? How Much Should it Be Hydrated?

The pack must be fully hydrated to perform optimally. Each cell expands to approximately 3 cm in thickness. Reference images typically show the difference between partially hydrated and fully hydrated sheets.

4. How Does Water Enter the Ice Pack? Should the Ice Pack Be Cut Before Hydration?

Dry ice packs use perforation technology to absorb water. Minute holes in the material allow water to enter and react with the polymer. Once hydrated, the polymer expands beyond the size of the perforations, remaining contained within each cell. Therefore, the pack does not need to be cut before soaking.

5. Does the Sheet Size Change After Hydration?

Yes. Once fully hydrated, the sheet becomes around 3 cm thick and may reduce by approximately 3 cm in both length and width, depending on hydration quality.

6. Will the Cells Continue to Expand After Hydration?

No. Once fully hydrated, cells will not continue to expand. However, over‑soaking can make the cells more prone to punctures. A properly hydrated cell will leave a slight indent when pressed with your thumb. This small indent allows for natural expansion during freezing.

7. Will the Dry Ice Pack Go Flat Again?

After extended storage or when used as a heat pack, sheets may dehydrate and flatten slightly. After approximately 4–5 uses, simply rehydrate by soaking or rinsing under water.

8. How Are Dry Ice Sheets Best Frozen or Heated?

As a Cold Pack

For cryotherapy, freeze for 3–4 hours to keep the pack semi‑solid and comfortable against the skin. If fully frozen, place a towel between the Ice pack and your body to prevent ice burn. Cold therapy should be used in 20‑minute intervals.

For Transport in an Icebox

Freeze for at least 24 hours. The colder the freezer, the longer the performance. For packing tips, see our guide.

Boiling Water Heating

The sheet can be heated up to 70°C. Heat by immersing in hot (off‑stove) water for 10 minutes. Wrap in a towel before use.

Steamer

Heating in a steamer is safer and minimises over‑hydration.

Microwave

Lay the sheet flat and heat for 40 seconds. Add further 10‑second increments as needed. Heating time varies with microwave power.

9. How Safe Is This Dry Ice Pack?

Cryolux dry ice packs are made from FDA‑approved, food‑grade materials in an ISO‑certified facility. The gel is non‑toxic and non‑hazardous, and safe for skin and food contact.

10. How Is a Cryolux Dry Ice Pack Better Than Ice?

Dry ice packs are cleaner, easier to handle, flexible when frozen, reusable, and last up to seven times longer than ice. They also double as heat packs.

11. How Long Will a Cryolux Sheet Stay Cold or Hot?

For therapy use, each cycle typically lasts several hours. For cold‑chain use (e.g., food, drinks, seafood, produce, medicines), performance depends on insulation quality and volume of ice packs used. Deep‑freezing or blast‑freezing extends cycle times.

12. How Are These Packs Used for Hot and Cold Therapy?

These packs are ideal for sports injuries, swelling, bruising, sprains, joint pain, cramps, haemorrhage control, dental extractions, and post‑surgical rehabilitation.

13. Advantages Compared to Blue Gel Packs

Blue gel packs freeze at around −4 to −5°C and are rigid when frozen. Cryolux packs freeze at −21°C, remain flexible, and can be cut to remove punctured cells. Blue gel packs must be discarded when punctured.

14. What Is the Lifespan of a Dry Ice Sheet?

When stored in original packaging, sheets last several years. Older sheets may hydrate more slowly; warm water helps. If cared for and kept puncture‑free, they can last many years.

15. Do These Packs Ever Leak?

The materials are semi‑permeable, so occasionally a thin film of gel may appear—typically when heated or after long storage. It is food‑safe and FDA‑approved. Rinsing the sheet resolves the issue.

16. How Should Dry Ice Sheets Be Stored?

Ideally store them in the freezer to help maintain freezer temperature and save energy. If short on space, store in a ventilated container to prevent mould. Rinse before use.

17. Can Cryolux Dry Ice Sheets Be Mixed with Crushed Ice?

Yes. For best performance, pair with dry ice or dry ice pellets. If mixing with water ice, place water ice at the bottom, food above it, and dry ice packs along the sides and top. The top layer should have two layers of dry ice packs to prevent warm air intrusion when opening the box.

18. What Is the Best Way to Cut a Cryolux Dry Ice Pack?

Cut along the seams after hydration, ensuring you do not puncture the gel‑filled cells. Fully hydrated sheets are easier to cut accurately.