How Flexible Dry Ice Packs Transform Cold Chain Logistics in 2025?
In 2025 the cold chain industry is under pressure: vaccines, biologics and gourmet foods must travel farther while staying ultra cold. Flexible dry ice pack sheets—lightweight blankets filled with solid carbon dioxide—offer a solution. Unlike rigid blocks, these sheets mold around irregular shapes and hold temperatures down to –78.5 °C. They keep sensitive products frozen for up to 72 hours without leaking water. This guide explores what makes flexible dry ice packs unique, how to size them correctly, the regulations you must follow, and the innovations shaping cold chain logistics.
What makes flexible dry ice packs unique? Understand how polymer cell technology delivers ultra cold temperatures and compare it with gel packs and phase change materials (PCMs).
How to size and apply flexible dry ice sheets? Follow simple 1:1 weight ratios and thickness guidelines for 24–72 hour shipments.
What safety and regulatory rules apply? Learn about Class 9 hazardous labels, UN 1845 markings, weight limits and ventilation requirements.
How do sustainability and market trends affect choices? Explore CO₂ supply shortages, hybrid PCM dry ice systems and eco friendly materials.
What innovations are coming? Discover biodegradable coatings, smart sensors and reusable solutions that reduce dry ice use.
What Makes Flexible Dry Ice Packs Unique Compared to Traditional Ice Packs?
Core insight: Flexible dry ice pack sheets are thin, pliable blankets filled with solid carbon dioxide or advanced PCMs. Their polymer cells are hydrated and frozen to form pockets that encapsulate dry ice, which sublimates at –78.5 °C to maintain ultra cold conditions. Traditional gel packs freeze at 0 °C and melt into liquid, delivering only moderate cooling and leaving water residue. This extreme temperature range lets flexible dry ice sheets keep vaccines, biologics and frozen seafood well below freezing for days.
Expanded explanation:
When you hydrate the super absorbent polymer cells and freeze them, the sheet becomes a flexible cold blanket. Dry ice absorbs heat at 571 kJ per kilogram while it sublimates directly into CO₂ gas. Because there is no melting, packages stay dry and there’s no risk of cross contamination. The sheets conform to irregular shapes, reducing dead air space and ensuring even cooling. In contrast, gel packs melt and release water, while PCMs maintain moderate ranges like 2–8 °C or –20 °C but cannot reach the ultra cold –78.5 °C needed for mRNA vaccines.
Understanding Dry Ice Sheets vs. Gel and PCM Packs
Flexible dry ice sheets offer advantages and trade offs compared with other refrigerants. The table below summarizes their temperature ranges, regulatory status and best use cases.
| Cooling medium | Typical temperature range | Regulatory classification | Residue after use | Best use cases | Practical significance |
| Flexible dry ice sheet | –78.5 °C to –20 °C; holds ultra cold temperatures for 24–72 hours | Class 9 hazardous material; requires UN 1845 labeling | Sublimates to CO₂ gas; no liquid residue | Frozen pharmaceuticals, biologics, specialty seafood | Maintains deep freeze conditions without moisture or soggy packaging |
| Gel pack | 0 °C to 5 °C; moderate cooling for 12–48 hours | Non hazardous; easy to handle | Melts into water, requiring leak proof packaging | Fresh produce, meal kits, short haul shipments | Provides mild refrigeration but not ultra cold temperatures |
| Phase change material (PCM) sheet | –20 °C to –70 °C; stable temperature band for 24–72 hours | Often non hazardous; PCMs are non toxic | Typically no residue; PCMs absorb heat during phase transitions | Biologics requiring strict 2–8 °C or –20 °C ranges | Offers reusable, narrow band temperature control without dry ice gas |
Practical Tips for Choosing Your Cold Pack
Ultra cold shipments: When your products must stay below –20 °C for more than a day, flexible dry ice sheets are the best choice. The sublimation of dry ice delivers powerful cooling without moisture.
Moderate cold conditions: Gel packs are cost effective for 2–8 °C shipments like fresh produce or meal kits.
Precise temperature bands: PCMs provide narrow ranges and reusable options for biologics that require strict 2–8 °C or –20 °C conditions.
Actual case: A biotech firm shipped mRNA vaccines wrapped with flexible dry ice sheets. The sheets maintained –75 °C for 72 hours despite external temperatures of 25 °C, and the vials arrived dry and uncontaminated.
How Do You Size and Apply Flexible Dry Ice Pack Sheets Effectively?
Core guidelines: Match the weight of dry ice to the weight of your product (a 1:1 ratio), and choose sheet thickness based on transit time. A 12 mm sheet typically preserves ultra cold temperatures for up to 24 hours, an 18 mm sheet lasts around 48 hours, and a 24 mm sheet can sustain frozen temperatures for up to 72 hours. Fully wrap the product or sandwich sheets between layers to maximize contact and uniform cooling.
Expanded explanation:
Dry ice sheets come in various thicknesses. The rate of sublimation decreases when the sheet is insulated and ambient temperatures are lower. Start by assessing your product’s temperature sensitivity and transit duration: if your cargo needs to remain below –20 °C for 48 hours, choose an 18 mm sheet; for 72 hours choose a 24 mm sheet or multiple 18 mm layers. Determine dry ice weight by matching it to the product weight; a 5 kg box of frozen seafood needs roughly 5 kg of dry ice. Hydrate the polymer cells evenly before freezing to ensure uniform sublimation. Pre chill your product and container to reduce the thermal load, then wrap the sheet around the cargo or place it above and below it (sandwich method). Use vented insulated containers with vacuum panels or expanded polystyrene to allow CO₂ gas to escape while retaining cold air.
Sizing Guidelines for Common Scenarios
| Transit duration | Recommended sheet thickness | Approximate dry ice weight per kg of product | Practical significance |
| Up to 24 hours | 12 mm flexible dry ice sheet | 1 kg dry ice per 1 kg product | Suitable for overnight shipments; keeps cargo below –20 °C for one day |
| 24–48 hours | 18 mm sheet or two 12 mm layers | 1–1.5 kg dry ice per kg product | Ideal for two day deliveries and international flights; layering adds redundancy |
| 48–72 hours | 24 mm sheet or three 12 mm sheets | 2 kg dry ice per kg product | Allows extended transit for vaccines and cell therapies; multiple layers keep –75 °C for three days |
Application Tips for Specific Use Cases
Laboratory samples: Wrap each specimen bag individually with a dry ice sheet and place absorbent pads underneath to capture condensation.
Meal kit services: Pre freeze food items, then wrap them with an 18 mm sheet and place additional sheets on top. The flexible nature of the sheet conforms to irregular shapes like whole fish or stacked steaks.
Pharmaceutical distribution: Use a 24 mm sheet for high value biologics. Employ real time temperature sensors to monitor conditions during transit.
Real world example: A meal kit company switched from rigid dry ice blocks to flexible sheets. By wrapping each parcel with a 12 mm sheet and adding an insulated liner, the company reduced dry ice usage by 20 % and maintained –18 °C for 48 hours.
What Safety and Regulatory Considerations Apply to Flexible Dry Ice Sheets?
Key points: Dry ice is classified as a Class 9 hazardous material under international air transport (IATA PI954) and U.S. DOT regulations. Packages must display the proper shipping name “carbon dioxide, solid” or “dry ice,” the United Nations number UN 1845, and the net weight of dry ice. Hazard labels should measure at least 100 mm on each side and weight limits typically cap at 200 kg per package. Flexible sheets do not change these requirements.
Expanded explanation:
Because dry ice sublimates into CO₂ gas, it can displace oxygen and pose suffocation risks. Always wear insulated gloves and eye protection when handling dry ice sheets. Use vented containers or shipping boxes with pressure relief valves so CO₂ gas can escape. Affix the Class 9 hazard label and note the net weight and UN 1845 identification number. Airlines and couriers may impose stricter limits; some restrict dry ice shipments to 10 kg per package on passenger aircraft. After delivery, allow remaining dry ice to sublimate in a well ventilated area away from children and pets, and recycle the polymer casing according to local regulations.
Training is essential: personnel must complete basic hazardous materials training and include documentation that states the net weight and shipping name. For biological samples, triple packaging is mandatory: a primary watertight receptacle, a secondary watertight container with absorbent material, and a strong outer box. Carriers like FedEx and UPS set additional rules; always check their current guidelines.
Compliance Checklist
| Requirement | Details | Importance |
| Proper shipping name & UN number | Label packages as “dry ice” or “carbon dioxide, solid,” and include UN 1845 | Ensures regulatory compliance and avoids fines |
| Net weight declaration | Record the weight of dry ice on the package (e.g., 5 kg) | Allows carriers to verify limits and plan ventilation |
| Class 9 hazard label | Use a diamond shaped label at least 100 mm per side with hazard symbol and number | Alerts handlers to potential hazards |
| Ventilation | Use vented packaging to let CO₂ gas escape | Prevents pressure buildup and suffocation |
| Personal protective equipment (PPE) | Wear insulated gloves and eye protection when handling sheets | Prevents frostbite and injury |
| Training & documentation | Ensure handlers are trained in hazardous materials and include required paperwork | Maintains safety and legal compliance |
Safety Tips for Users
Use vented containers: Never seal dry ice inside airtight plastic bags or jars. Always choose containers designed with pressure relief vents.
Monitor CO₂ levels: Use CO₂ monitors in storage areas to detect accumulation, especially in confined spaces such as vehicles or small warehouses.
Limit quantities in aircraft: On passenger flights, travelers may carry up to 2.5 kg of dry ice without additional paperwork, but commercial shipments can carry up to 200 kg per package.
Dispose responsibly: Allow dry ice to sublimate in open air away from children and pets and never flush it down the drain.
Real world lesson: In 2024 a pharmaceutical distributor sealed dry ice sheets inside an airtight plastic wrap. CO₂ built up, rupturing the package and delaying the shipment. After switching to vented boxes and proper labeling, the company achieved full compliance.
How Do Sustainability and Market Trends Shape Flexible Dry Ice Packs in 2025?
Market dynamics: Demand for dry ice has been growing about 5 % annually, while CO₂ supply increases only 0.5 % per year. This imbalance has created shortages and caused prices to spike by up to 300 % in some regions. The global dry ice market was valued at around USD 1.54 billion in 2024 and is projected to reach USD 2.73 billion by 2032, with a compound annual growth rate of about 7.4 %. Similarly, the cold chain packaging refrigerants market—including dry ice, gel packs and PCMs—was valued at USD 1.57 billion in 2024 and is expected to grow to USD 2.92 billion by 2032 at a CAGR of 8.14 %. Europe led this market with a 31.85 % share in 2024.
Sustainability pressures: Environmental concerns and stricter regulations are pushing manufacturers toward greener production. Many dry ice sheets now use recycled CO₂ and biodegradable polymers. Sustainable coatings reduce frost buildup and extend cooling performance. Companies like Marken and Peli BioThermal have introduced reusable dry ice shippers that reduce dry ice use by 50 % and cut waste by up to 90 %, while maintaining precise temperature control. At the same time, bio based CO₂ from fermentation (e.g., bioethanol plants) is being captured and used to produce dry ice, reducing reliance on fossil based sources.
Market innovations: To mitigate supply shortages, producers are building localized CO₂ capture hubs and exploring on site production at food and beverage plants. Shippers are diversifying cooling strategies, mixing dry ice with PCMs and investing in better insulation to stretch each kilogram of dry ice. Hybrid systems that combine dry ice sheets with –20 °C PCMs can extend frozen duration by 40 %. Vacuum insulation panels reduce sublimation loss from 8 % per day to about 3 %. These trends lower costs, improve sustainability and allow shippers to meet strict temperature requirements.
Market Dynamics and Environmental Innovations
| Trend or innovation | Description | Practical impact for users |
| Local CO₂ sourcing | Capturing CO₂ from fermentation, ammonia and ethanol plants for dry ice production | Reduces dependence on fossil fuels and stabilizes supply, lowering costs |
| Biodegradable polymers | Using compostable or recyclable materials for sheet casings | Simplifies disposal and appeals to eco conscious customers |
| Smart monitoring | Embedding temperature and location sensors in sheets | Improves transparency, reduces product loss and enables real time interventions |
| Hybrid cooling systems | Combining dry ice sheets with PCMs or gel packs | Reduces dry ice consumption, lowers costs and eases regulatory burden |
| Improved insulation | Adoption of vacuum panels and reflective liners reduces sublimation from 8 % to 3 % per day | Allows lighter packages and longer hold times |
Market story: Facing a CO₂ shortage in 2023–2024, a seafood exporter installed a CO₂ capture unit at a nearby brewery. By pairing locally sourced dry ice with upgraded insulation and smart sensors, the company maintained shipments below –30 °C for 60 hours while reducing dry ice use by 30 %.
Comparing Flexible Dry Ice Packs with Other Cold Chain Refrigerants
Overview: Gel packs, water packs, dry ice and reusable cold packs each serve different temperature ranges and logistics needs. Gel packs and water packs are safe and cost effective for 2–8 °C shipments, while dry ice delivers ultra cold conditions for frozen goods. Reusable cold packs provide low long term cost but require return logistics.
Advantages and Disadvantages of Cold Pack Types
| Cold pack type | Best use | Pros | Cons | Overall suitability |
| Gel packs | 24–48 hour chilled shipments (2–8 °C) | Better thermal retention than water packs, non toxic and easy to handle | Risk of leakage and higher cost per unit | Suitable for fresh produce, meal kits and pharma at chilled range |
| Water (ice) packs | Short to mid duration chilled shipments | Low cost, safe disposal, no toxicity | Less thermal mass and risk of leaks | Good for cost sensitive chilled shipments |
| Dry ice packs | Frozen goods (seafood, meats, ice cream) | Provides extremely low temperatures and long duration freezing | Hazardous classification, overcooling risk and higher cost | Essential for deep frozen shipments when compliance and safety are managed |
| Reusable cold packs | Subscription services, pharma delivery with return logistics | Low long term cost and reduced waste | Requires return logistics and high upfront investment | Ideal for closed loop systems with high return rates |
PCM vs. Dry Ice: Choosing the Right Solution
Phase change materials absorb and release heat at predefined temperatures and are reusable. They are engineered to maintain specific ranges like 2–8 °C or –20 °C and are typically non hazardous. Dry ice sublimates at –78.5 °C, making it effective for ultra cold shipments but subject to hazardous materials rules. For shipments requiring deep freeze temperatures (< –70 °C), dry ice remains indispensable; for temperatures between 2–8 °C or –20 °C, PCMs offer stable temperature control and reduced regulatory complexity. Hybrid solutions integrate PCMs and dry ice to extend cooling and minimize hazardous materials.
2025 Innovations and Future Outlook for Flexible Dry Ice Sheets
Trend overview: The future of flexible dry ice sheets lies at the intersection of material science, digitalization and regulation. Emerging innovations include biodegradable coatings to slow sublimation and reduce frost, smart sensors that send real time temperature and location data, 3D forming technology for custom shapes, and hybrid systems combining dry ice with PCMs to extend shipping windows. Vacuum insulation panels further reduce heat transfer and allow shippers to use thinner sheets.
Latest Advances at a Glance
Biodegradable dry ice sheets: Pilot trials are moving toward mainstream adoption, allowing composting or recycling after use.
Sensor enabled sheets: Commercially available sheets now embed temperature, humidity and location sensors that transmit data to dashboards, enabling proactive interventions.
Hybrid ice/PCM solutions: Hybrid designs reduce dry ice usage by up to 40 % by pairing dry ice with –20 °C PCMs.
Market insights: Analysts forecast the global dry ice and alternative refrigerant market to grow from USD 1.54 billion in 2024 to USD 2.73 billion by 2032. Suppliers should monitor regulatory changes that may relax hazardous materials rules for flexible sheets and strengthen guidelines for PCMs. Investing in IoT enabled packaging can reduce spoilage and improve compliance. Diversifying refrigerant options—combining dry ice with PCMs and improved insulation—will mitigate supply risks and control costs.
FAQ
Question 1: How long do flexible dry ice sheets last?
A properly sized sheet maintains ultra cold temperatures for 24–72 hours. Duration depends on sheet thickness—12 mm for one day, 18 mm for two days and 24 mm for three days—and on insulation quality.
Question 2: Can flexible dry ice sheets be reused?
No. Once the dry ice has fully sublimated, the sheet no longer provides cooling. The polymer casing can be recycled depending on local regulations. For reusable solutions, consider PCM or gel packs.
Question 3: How do I dispose of flexible dry ice sheets safely?
Let remaining dry ice sublimate in a well ventilated area away from children and pets. Do not flush dry ice down the drain or place it in airtight bins. Once sublimated, dispose of or recycle the casing according to municipal guidelines.
Question 4: Are flexible dry ice sheets safe for air transport?
Yes, but they are subject to IATA PI954 regulations. Packages must display the proper label (“dry ice,” UN 1845), net weight and hazard symbol. Ventilation and weight limits (typically 200 kg per shipment) must be respected.
Question 5: What’s the difference between flexible dry ice sheets and PCM sheets?
Dry ice sheets reach –78.5 °C and are single use but require hazardous materials compliance. PCM sheets maintain specific ranges (2–8 °C or –20 °C) and are reusable, non hazardous and easier to dispose of. Hybrid packs combine both to extend cooling.
Question 6: Can I ship food with flexible dry ice packs?
Yes. They are ideal for frozen foods like seafood or ice cream. For chilled items such as produce or dairy, gel or water packs may be more suitable. Always match the refrigerant to the temperature requirements of your product.
Summary
Key takeaways: Flexible dry ice packs offer ultra cold temperatures down to –78.5 °C, wrapping around irregular shapes without leaving moisture. Proper sizing (1:1 dry ice-to-product ratio) and sheet thickness (12–24 mm) are essential for achieving 24–72 hour hold times. Dry ice is a Class 9 hazardous material requiring UN 1845 labels, weight declarations and vented packaging. Sustainability pressures and CO₂ shortages drive innovation: biodegradable materials, hybrid PCM dry ice systems and smart sensors are emerging. Dry ice market growth and regulatory changes make it important for shippers to diversify cooling strategies.
Actionable advice: Assess your product’s temperature tolerance and transit duration. For ultra cold shipments, choose flexible dry ice sheets and follow sizing guidelines; for chilled goods, opt for gel or water packs. Always train staff in hazardous materials handling and comply with IATA and DOT regulations. To reduce costs and environmental impact, explore hybrid PCM dry ice systems, invest in insulated containers and monitor CO₂ sourcing trends. Lastly, implement smart sensors to track temperature and location, improving compliance and reducing spoilage.
ABout Tempk
Company profile: Tempk specializes in cold chain packaging solutions, including flexible dry ice sheets, gel packs, PCMs and insulated containers. We leverage our R&D expertise to create products that hold temperatures from 0 °C down to –78.5 °C. Our dry ice sheets incorporate super absorbent polymers that are lightweight, moldable and easy to handle. We prioritize sustainable materials and have developed biodegradable casings to reduce environmental impact. With a global presence and stringent quality certifications, we support pharmaceutical, food and biotech industries.
Call to action: If you need guidance on selecting the right refrigerant or designing a compliant shipping system, contact Tempk’s experts. We can provide customized solutions tailored to your product’s temperature requirements, transit time and sustainability goals.
