How Dry Ice Sheets and Packs Keep Shipments Frozen in 2025
Dry ice sheets and packs aren’t just cold — they’re super cold. The solid carbon dioxide blocks embedded in these flexible packs reach –78.5 °C (–109.3 °F) and consistently absorb heat as they sublimate. Thanks to these ultra low temperatures, dry ice solutions can preserve frozen foods, biologics and medicines for up to 48–72 hours. With the global cold chain market projected to exceed $1.6 trillion by 2033, mastering dry ice technology helps your business stay competitive. This article uses plain language to explain the differences between dry ice sheets and dry ice packs, how to calculate your cooling needs, and why 2025 trends matter to you.
What are dry ice sheets and packs? Discover how they differ from gel packs and why dry ice reaches –78.5 °C.
How do dry ice solutions compare to traditional ice and gel packs? See the benefits and drawbacks of each option, including moisture free cooling.
How much dry ice do you need for different shipments? Learn a simple 1:1 rule and adjustment factors for season, route and insulation.
What packaging setups maximize performance? Explore top placement and hybrid packouts, and how they extend duration.
What safety practices are essential when handling dry ice? Understand the hazards of carbon dioxide gas and frostbite.
What are the emerging trends for 2025? Learn about smart monitoring, sustainable materials and ready to use kits.
What Are Dry Ice Sheets and Packs? Why Are They Different from Traditional Ice?
Dry ice sheets and packs are flexible, sealed pouches filled with solid carbon dioxide pellets or blocks. Unlike gel packs that freeze around 0 °C and gradually thaw, dry ice sublimates directly from solid to gas, releasing no liquid. This means your parcels stay moisture free, and there’s no risk of soggy packaging or water damage. Traditional ice melts at 0 °C and lasts only 12–24 hours, making it suitable for short journeys or products that only require refrigeration. In contrast, dry ice sheets maintain –78.5 °C to –18 °C for 24–48 hours, while disposable dry ice packs can last up to 72 hours when properly insulated.
How Dry Ice Works: Sublimation Explained
Dry ice is simply the solid form of carbon dioxide. At atmospheric pressure it does not melt into liquid; instead it sublimates directly into gas. During sublimation, the dry ice absorbs heat from its surroundings, keeping your shipment cold. Because it transitions to gas, there’s no watery residue, which is why dry ice is the preferred choice for ultra low temperature shipping. However, the carbon dioxide gas released can accumulate and displace oxygen in confined spaces, so proper ventilation is crucial.
Dry Ice Sheets vs. Mini and Disposable Packs
| Cooling Solution | Temperature Range | Typical Duration | What It Means for You |
| Mini dry ice sheet | –78.5 °C to –18 °C | 24–48 h | Ideal for pharmaceuticals or biologics requiring constant ultra low temperatures; no moisture risk |
| Disposable dry ice pack | –78.5 °C | Up to 72 h | Perfect for long distance shipping of frozen meat, seafood or vaccines; single use convenience |
| Gel pack | 2 °C–8 °C | Up to 48 h | Keeps produce, dairy or medicines cool without freezing; reusable but may leak |
| Traditional water pack | ≈0 °C | 24–36 h | Inexpensive solution for short journeys; limited thermal mass and moisture leakage risk |
Why Choose Dry Ice Over Gel Packs?
Dry ice offers super cold temperatures and longer cooling duration. Coldkeepers, a packaging specialist, notes that dry ice can maintain temperatures as low as –109.3 °F (–78.5 °C) and lasts longer than gel packs in insulated containers. Because dry ice sublimates, it leaves no liquid residue, preventing soggy packages. However, dry ice requires special handling and proper labeling due to its hazardous classification; shipping carriers may impose quantity limits. Gel packs are non toxic and safe to handle, making them suitable when recipients are inexperienced with dry ice. For refrigerated temperatures (2–8 °C) or short trips, gel packs are cost effective.
How Much Dry Ice Do You Need for Your Shipment?
The amount of dry ice depends on your product weight, route, insulation and ambient conditions. A simple rule of thumb is a 1:1 ratio of dry ice weight to product weight for 48 hour shipments. For example, shipping 8 lb of frozen seafood would start with 8 lb of dry ice sheets. Adjust your dry ice amount using three factors:
Seasonal temperatures: Summer shipments need 25–35 % more dry ice than winter shipments because higher ambient temperatures accelerate sublimation.
Route complexity: Multi handoff routes require an additional 10–15 % dry ice to buffer delays.
Insulation quality: Better insulation can reduce dry ice requirements by 10–25 %. Upgrading from standard foam to vacuum insulated panels cuts dry ice needs, saves weight and lowers costs.
Dry Ice Sizing Examples and Practical Tips
| Product Weight | Starting Dry Ice (1:1) | When to Add More | Practical Benefit |
| 4 lb | 4–5 lb | Hot climates or peak summer | Ensures 48 hour freeze protection |
| 8 lb | 8–10 lb | Complex routes with multiple handoffs | Consider vacuum insulation if weight is restricted |
| 12 lb | 12–15 lb | Very hot lanes or delays | Combine hybrid packouts with monitoring |
Summer seafood shipment: Add 35 % more dry ice and include a temperature logger. Pharmaceutical samples: Use vacuum insulated panels to reduce dry ice by 20 %. Multi stop deliveries: Increase dry ice by 15 % and use hybrid packouts. These adjustments ensure your products remain frozen even when conditions vary.
Which Packaging Setup Delivers Reliable 48 Hour Performance?
For maximum effectiveness, place dry ice sheets on top of your frozen goods inside an insulated container. Cold air naturally sinks, so top placement ensures uniform cooling and reduces carbon dioxide buildup. Include void filling materials—such as foam pads or crumpled paper—to prevent air pockets and keep the ice in place. Precondition products by freezing them below –18 °C and chilling packaging materials before assembly.
Top vs. Surround vs. Hybrid Layouts
| Layout Type | Sublimation Rate | Duration | Best For |
| Top Placement | 8–12 % per 24 h | 24–36 h | Standard shipments and shorter routes |
| Surround Layout | 6–9 % per 24 h | 36–60 h | Sensitive products needing even cooling |
| Hybrid Layout | 5–8 % per 24 h | 48–72 h | Extended journeys or high value goods |
Hybrid packouts combine dry ice sheets on top and along the sides, often with phase change materials for buffering. Layering thinner sheets instead of a single block provides more consistent sublimation and reduces thermal shock. Always pre chill your packaging components and use temperature loggers to validate performance.
Advanced Packing Techniques
Hybrid packouts: Mix dry ice with phase change materials to buffer temperature fluctuations.
Void control: Eliminate air spaces with foam pads or paper to stabilize temperature.
Layered approach: Use multiple thin dry ice sheets for gradual sublimation.
Safe Handling and Storage of Dry Ice
Dry ice is extremely cold (–78 °C) and can cause frostbite upon contact. It releases large volumes of carbon dioxide gas—10 kg of dry ice sublimates into approximately 5.4 m³ of CO₂—which can displace oxygen and cause asphyxiation in poorly ventilated spaces. Safe handling practices include:
Wear insulated gloves and eye protection. Do not handle dry ice with bare hands.
Provide ventilation. Never seal dry ice in airtight containers; always allow gas to escape. Avoid transporting dry ice in a car or confined space; if you must, ensure adequate ventilation.
Store properly. Use insulated, vented containers and keep the lid closed when not in use. Do not store dry ice in cellars or unventilated rooms. Water accelerates sublimation, increasing asphyxiation risk.
Label shipments. Dry ice is classified as UN1845; packages must display the net weight and carry a 100 mm × 100 mm Class 9 hazard label.
Treat frostbite correctly. If skin contacts dry ice, remove clothing that isn’t frozen to the skin and immerse the area in warm water (below 40 °C); never rub the area.
Following these precautions protects you and your customers. Training staff on emergency procedures and providing safety instructions to recipients further reduces risk.
Validating and Monitoring Performance
The best way to ensure your dry ice shipment meets its target duration is to validate and monitor. Start by bench testing your packaging using standard temperature profiles such as ISTA 7E or Standard 20. Measure temperatures at the core and near the walls to identify weak points. Then perform real world lane pilots with extra dry ice—about 25–50 % buffer—to account for handling delays and route variability. Use temperature loggers for basic validation, IoT sensors like FedEx SenseAware for real time tracking, and NFC enabled devices for compliance documentation. Monitoring CO₂ levels in staging areas can prevent gas buildup.
Latest Trends and Innovations in 2025
Technological and Market Developments
The cold chain market is expanding rapidly. Grand View Research projects it will reach $1.611 trillion by 2033 with a 20.1 % compound annual growth rate (CAGR). North America held over 33 % of revenue share in 2024, while the equipment segment is expected to grow from $94.3 billion in 2025 to $179.8 billion by 2034. Rising e commerce demand for fresh foods and increasing pharmaceutical shipments drive this growth.
Innovations Shaping Dry Ice Shipping
Smart temperature monitoring: IoT sensors send real time alerts when temperature deviates, allowing proactive intervention.
Sustainable packaging: Manufacturers are developing recyclable thermal shippers that maintain temperature for 72 + hours and gel packs using biodegradable materials.
Blockchain transparency: Distributed ledger technology improves traceability and accountability across the supply chain.
Hybrid refrigeration: Electric and hybrid transport units reduce reliance on diesel and lower emissions.
Ready to use kits: Preassembled thermal kits simplify training and reduce packing errors.
Circular economy: Dry ice production often repurposes CO₂ from industrial processes, reducing carbon footprint and supporting sustainability.
Market Insight and Consumer Preferences
Consumers are increasingly environmentally conscious. Businesses are therefore balancing performance with sustainable materials and exploring carbon neutral strategies like CO₂ capture and recycling. For high value biologics, phase change materials and vacuum insulated panels provide precise temperature control while reducing ice requirements. Meal delivery services leverage mini dry ice sheets to keep frozen meals at –20 °C for 24 hours, ensuring food arrives fresh. Pharmaceutical companies rely on mini dry ice sheets to maintain –78.5 °C for more than 48 hours, enabling global vaccine distribution.
Frequently Asked Questions
Q1: How long do dry ice sheets last in transit?
Most dry ice sheets maintain –78.5 °C to –18 °C for 24–48 hours. Disposable packs can extend this to up to 72 hours when combined with quality insulation.
Q2: Can dry ice sheets be used with pharmaceuticals?
Yes. Mini dry ice sheets provide consistent ultra low temperatures ideal for vaccines requiring –70 °C. Always use temperature data loggers and follow regulatory guidelines.
Q3: Do dry ice sheets make packages wet?
No. Dry ice sublimates directly to carbon dioxide gas, leaving no liquid residue, unlike water based packs.
Q4: Are dry ice sheets safe for home delivery?
Dry ice is safe when handled properly. Wear insulated gloves, provide ventilation, and include clear disposal instructions to recipients. For recipients unfamiliar with dry ice, gel packs may be safer.
Q5: How can I reduce the environmental impact of using dry ice?
Opt for dry ice produced from recycled CO₂ and use only the amount needed. Reuse or recycle packaging materials, and consider hybrid solutions combining dry ice with reusable gel packs to minimize waste.
Summary and Recommendations
Dry ice sheets and packs are powerful tools for maintaining frozen temperatures in 2025. By leveraging the 1:1 sizing rule and adjusting for season, route and insulation, you ensure consistent performance. The right packout configuration—top, surround or hybrid—extends duration, while proper handling and ventilation mitigate hazards. Innovations like smart sensors and sustainable materials are shaping the future of cold chain logistics.
Next Steps for Your Cold Chain Strategy
Assess your shipment needs. Determine product weight, required temperature and transit duration.
Calculate dry ice requirements. Start with a 1:1 ratio and adjust for seasonal and route variables.
Choose the right packaging. Select between top, surround or hybrid layouts and invest in quality insulation.
Implement monitoring. Use temperature loggers and IoT sensors to validate performance.
Educate your team and customers. Train staff on safe handling and include clear instructions for recipients.
Explore sustainable options. Evaluate gel pack hybrids and recyclable materials to align with environmental goals.
By following these steps, you’ll optimize your cold chain operations and deliver products safely, cost effectively and sustainably.
About Tempk
At Tempk, we specialize in high performance temperature control solutions. Our dry ice sheets and mini packs maintain –78.5 °C cooling performance while offering moisture free operation. We also provide insulated packaging, IoT monitoring tools and custom hybrids to suit your specific needs. Our commitment to innovation, sustainability and regulatory compliance ensures your shipments reach their destination safely. Contact us today to optimize your cold chain logistics and stay ahead of 2025 trends.
