Long Lasting Dry Ice Pack: How to Keep Shipments Cold for Days
Shipping frozen goods isn’t just about throwing ice into a box—it’s about choosing the right refrigerant and packing it correctly so your products arrive safely. A long lasting dry ice pack offers extreme cold without messy meltwater and can keep shipments frozen for days when used properly. In this comprehensive guide you’ll learn what makes dry ice packs so effective, how to select and handle them, and what innovations are shaping cold chain logistics in 2025. Whether you’re shipping seafood, vaccines or gourmet desserts, this article will help you maintain quality and reduce waste.
Understand why long lasting dry ice packs outperform traditional ice packs for frozen shipments.
Choose the right quantity and format of dry ice using easy formulas and tables.
Compare dry ice packs with gel packs and phase change materials to pick the ideal cooling medium.
Follow safety and regulatory guidelines to avoid hazards and comply with UN 1845 requirements.
Explore 2025 innovations in smart sensors, sustainable materials and AI-driven cold chain logistics.
Get answers to common questions about duration, reuse and carrier acceptance of dry ice packs.
What Makes a Long Lasting Dry Ice Pack So Effective for Shipping?
When your product must stay frozen from pickup to delivery, dry ice delivers reliable performance. Dry ice is the solid form of carbon dioxide and sublimates (turns directly from solid to gas) at −78.5 °C. This sublimation absorbs heat and maintains extremely low temperatures without leaving moisture. Traditional water ice melts around 0 °C and leaves condensation; gel packs freeze around −18 °C and leak liquid if punctured. Dry ice, by contrast, produces no liquid, making it ideal for pharmaceuticals and electronics. It’s so cold, in fact, that it can burn skin if touched without gloves.
Sublimation and Cooling Capacity
When a long lasting dry ice pack begins to warm, it sublimates directly into carbon dioxide gas, absorbing heat from its surroundings. Because there is no liquid phase, sensitive products remain dry. Dry ice maintains temperatures down to −78.5 °C—far colder than gel packs or water packs. The cooling power comes from the latent heat of sublimation: for every kilogram of dry ice that sublimates, roughly 571 kJ of heat is absorbed. This means a small amount of dry ice can provide considerable cooling capacity. In practice, 5–10 lb (2.27–4.54 kg) of dry ice will keep a shipment frozen for roughly 24 hours. Doubling the weight roughly doubles the duration, although environmental factors, insulation and void space also play roles.
Advantages Over Traditional Ice
Traditional ice and gel packs serve chilled shipping but struggle with deep freeze temperatures. Dry ice packs offer several advantages:
| Feature | Dry Ice Packs | Gel Packs | What It Means for You |
| Temperature Range | Down to −78.5 °C | 0 °C to −18 °C | Dry ice packs maintain lower temperatures—essential for frozen meats, biologics and ice cream. |
| Moisture Risk | None (sublimates to gas) | Moderate—melts to liquid | No condensation means packaging and products stay dry, preventing soggy boxes or damaged goods. |
| Duration | Up to 72 hours when properly packed | 24–48 hours for gels | Longer transit times are possible with dry ice, reducing the need for refrigerated transport or expedited shipping. |
| Regulation | Classified as hazardous (UN 1845) | Not regulated | You need to follow shipping guidelines for dry ice, but the benefits often outweigh the extra paperwork. |
| Reuse | Most dry ice packs are single use, though reusable versions exist | Generally reusable | Reusable dry ice packs reduce waste and cost over time, making them attractive for recurring shipments. |
From this comparison it’s clear that long lasting dry ice packs are best for shipments requiring deep freeze temperatures and zero moisture. Gel packs remain useful for chilled goods (2–8 °C) or when regulations make dry ice impractical, but they can’t match the extreme cold and duration of dry ice packs.
Real World Example
Consider a gourmet ice cream company shipping premium pints nationwide. During summer the ice cream must remain below −20 °C for 48 hours. Using gel packs alone, the company experienced melting and product loss. Switching to long lasting dry ice packs improved outcomes: a 10 lb shipment with 15 lb of dry ice maintained the required temperature for 72 hours, even when ambient temperatures exceeded 30 °C. Customer complaints dropped, and shipping costs decreased because the company could use ground shipping instead of costly air freight.
Practical Tips and Suggestions
Select the correct format: Blocks of dry ice sublimate slowly, making them ideal for long trips. Pellets offer rapid cooling but vaporize faster. Sheets distribute CO₂ evenly and are easy to handle.
Avoid overcooling: If your product shouldn’t freeze (e.g., certain pharmaceuticals), consider gel packs or phase change materials instead. Dry ice may damage items not meant to be frozen.
Combine with high quality insulation: A well designed insulated box slows sublimation and extends hold times. Pre chill containers to reduce thermal shock.
Minimize void space: Use filler materials or cut sheets to fit snugly around products. Empty gaps accelerate sublimation.
Case Study: A biotech company shipped gene therapy samples requiring −60 °C storage. By combining custom cut dry ice sheets with vacuum insulated panels, the company maintained target temperatures for 60 hours, reducing dry ice consumption by 30%. This efficiency saved shipping costs and minimized CO₂ emissions.
How to Choose the Right Long Lasting Dry Ice Pack for Different Shipments?
Selecting a long lasting dry ice pack isn’t one size fits all. Shipment weight, transit duration, ambient conditions and regulatory limits determine how much dry ice you need. Overusing dry ice wastes money and increases hazards; underusing it risks product loss. This section provides simple formulas, tables and guidelines to help you make informed decisions.
Estimating the Required Dry Ice Quantity
According to industry guidelines, the amount of dry ice needed is roughly proportional to product weight and transit time. The cryogenic dry ice pack guide suggests 5–10 lb (2.27–4.54 kg) of dry ice per 24 hours of transit. To calculate a baseline amount:
dry_ice_weight (lb) = product_weight (lb) × transit_days × 0.5
Example: A 10 lb shipment traveling for 3 days requires about 15 lb of dry ice (10 lb × 3 × 0.5). Adjust the result upward in hot weather or downward in cooler climates.
Dry Ice Quantity Table
The table below summarizes recommended dry ice amounts for typical shipment sizes and durations. These values include an extra safety margin for warm ambient temperatures.
| Product Weight | Dry Ice for 24 hrs | Dry Ice for 48 hrs | Dry Ice for 72 hrs | Practical Meaning |
| 2 lb (0.9 kg) | 5 lb | 8 lb | 10 lb | Suitable for small vaccine shipments or gourmet chocolates. |
| 5 lb (2.3 kg) | 6 lb | 9 lb | 12 lb | Ideal for frozen meal kits or seafood. |
| 10 lb (4.5 kg) | 10 lb | 15 lb | 20 lb | Useful for bulk meat orders and diagnostic samples. |
| 20 lb (9 kg) | 15 lb | 22 lb | 30 lb | Appropriate for large lab shipments or multiple vaccine vials. |
| 50 lb (22.7 kg) | 20 lb | 33 lb | 45 lb | Recommended for organ transport or industrial reagents. |
Factors Affecting Dry Ice Requirements
Product Weight and Density: Heavier or high density products absorb more heat, requiring more dry ice.
Transit Duration: Longer journeys need more dry ice. Always plan for possible delays.
Ambient Temperature: Shipments in hot climates or during summer need extra dry ice.
Insulation Quality: Thick, high performance insulated containers reduce the dry ice needed.
Package Design: Poorly designed containers allow too much heat in; pre cool containers and minimize void space.
Format and Packaging Considerations
Dry ice comes in various formats—blocks, pellets, nuggets, slices and sheet packs. Large blocks sublimate slowly and are ideal for long distance shipments. Pellets and nuggets provide rapid cooling but evaporate quickly and are best for short hauls or pre chilling. Sheets are flexible pads filled with dry ice particles encased in breathable cells; they distribute cooling evenly and can be trimmed to fit any container.
Tip: For shipments requiring both rapid and sustained cooling, layer different formats—place pellets above the products for quick temperature drop and blocks below for extended duration.
Customizing Dry Ice Packs for Your Box
Long lasting dry ice packs can be cut and configured to fit oddly shaped containers. For example, a laboratory shipping irregularly sized diagnostic devices used custom cut dry ice sheets that filled void spaces and maintained uniform temperatures, reducing sublimation loss by 15%. To replicate this:
Measure the internal dimensions of your insulated container.
Cut the dry ice sheet with a serrated knife while wearing insulated gloves and goggles.
Place products in the center and surround them with the dry ice sheet, ensuring vents are clear to allow CO₂ gas to escape.
Real World Example: A clinical trial site shipped biologic samples across a desert region. By tailoring dry ice sheets to the box interior and pre chilling the container, they maintained samples below −40 °C for 48 hours while reducing dry ice weight by 20%. This saved shipping costs and simplified compliance documentation.
Comparing Long Lasting Dry Ice Packs with Gel Packs and Phase Change Materials: Which Is Best?
Cold chain shippers often ask whether dry ice, gel packs or phase change materials (PCMs) offer the best solution. Each refrigerant serves a distinct purpose. This section compares long lasting dry ice packs with alternatives so you can match the refrigerant to your shipment.
Dry Ice vs. Gel Packs
Gel packs are flexible pouches filled with refrigerant designed to maintain refrigerated temperatures (2–8 °C). They are best for 24–48 hour chilled shipments and are not heavily regulated. Advantages include lower cost per unit and ease of handling, but they can leak if punctured and are often non recyclable. Dry ice packs, by contrast, deliver extremely low temperatures and longer duration. However, they are classified as hazardous material (UN 1845) and require special handling and documentation.
When to choose dry ice:
Your product must remain frozen (below −20 °C) for more than 24 hours, such as ice cream, frozen meat or temperature sensitive biologics.
Moisture would damage the product (e.g., electronics, vaccines).
You can comply with regulations and have trained staff to handle hazardous materials.
When to choose gel packs:
Your product needs to stay cool but not frozen (2–8 °C), such as dairy, cheese or certain pharmaceuticals.
Shipment durations are short (24–48 hours).
You want minimal regulatory requirements.
Dry Ice vs. Phase Change Materials (PCMs)
Phase change materials are engineered substances that maintain a specific temperature (e.g., +5 °C or +20 °C) during melting and solidifying. They are used for sensitive biologics requiring narrow temperature bands. PCMs deliver predictable temperatures with less risk of freezing or overheating but are more expensive and require pre conditioning at target temperatures. Dry ice remains unmatched for ultra cold conditions but lacks the precision of PCMs.
When to choose PCMs:
You need a precise temperature range—for example, +2 °C to +8 °C for clinical samples, or +15 °C to +25 °C for chemical reagents.
Your shipment will travel through climates that could freeze or overheat your product; PCMs buffer against extremes.
Hybrid solutions: Many companies layer dry ice with gel packs or PCMs. For instance, you might place dry ice at the bottom to maintain freezing while using a PCM panel above to prevent supercooling of temperature sensitive products. Improved insulation technologies, such as vacuum panels, further reduce the amount of dry ice needed.
Summary Comparison Table
| Cooling Medium | Temperature Range | Regulation | Pros | Cons | Best For |
| Long Lasting Dry Ice Pack | Down to −78.5 °C | Hazardous (UN 1845) | Extreme cooling power, no moisture, long duration | Requires special handling; can overcool products | Frozen food, vaccines, biological samples requiring deep freeze. |
| Gel Packs | 0 °C to −18 °C | Not regulated | Flexible, safe handling, reusable | Shorter duration; risk of leakage; moderate cooling | Chilled goods, meal kits, dairy. |
| PCMs | Custom (e.g., +2 °C to +8 °C) | Not regulated | Precise temperature control; low moisture | Higher cost; requires pre-conditioning | Clinical samples, biologics requiring tight temperature bands. |
Real World Scenario
A meal kit company ships dinners across the country. For fresh ingredients, it uses gel packs because the kits need to stay between 2 °C and 8 °C and must not freeze. For frozen components like ice cream add ons, the company inserts a long lasting dry ice pack at the bottom and places gel packs on top. This hybrid approach maintains ideal temperatures across compartments and meets regulatory guidelines.
Best Practices for Using Long Lasting Dry Ice Packs: Safety, Packing and Regulation
While dry ice packs deliver exceptional cooling, they come with hazards and regulatory obligations. Dry ice can burn skin, release large volumes of carbon dioxide gas and cause pressure buildup if sealed improperly. Moreover, dry ice is classified as a hazardous material (UN 1845) and must be shipped according to specific guidelines. Following best practices protects both your staff and your products.
Safety Guidelines
Wear protective gear: Dry ice’s extreme cold can cause frostbite. Always use insulated gloves and safety goggles when handling dry ice.
Ensure adequate ventilation: CO₂ gas can displace oxygen in confined spaces and pose asphyxiation risks. Handle dry ice in ventilated areas and avoid placing it in airtight fridges or freezers.
Use ventilated containers: Packages must allow CO₂ gas to escape to prevent pressure buildup. Never seal dry ice in plastic bags or airtight coolers.
Avoid direct ingestion: Dry ice can cause internal injuries if swallowed. Keep it away from children and pets.
Educate personnel: Provide training on proper handling, emergency response and disposal.
Dispose of dry ice safely: Allow dry ice to sublimate in a well ventilated area. Never dispose of it in sinks or drains, as extreme cold can damage plumbing.
Packaging and Labeling Requirements
Shipping dry ice requires compliance with regulations set by agencies such as the International Air Transport Association (IATA) and the U.S. Department of Transportation (DOT). Key requirements include:
Vent for CO₂ release: Packaging must allow venting of carbon dioxide gas.
Use strong containers: Choose fiberboard, plastic or wooden boxes that can withstand pressure changes and temperature fluctuations. Avoid plastics that become brittle at low temperatures.
Mark packages clearly: Label boxes with the proper shipping name “Dry Ice, 9, UN 1845,” the names and addresses of the shipper and consignee, and the net weight of dry ice in kilograms.
Apply hazard labels: Place a Class 9 hazard label on two sides of the package.
Observe quantity limits: Maximum dry ice per package is typically 200 kg for air shipments; carriers may impose additional restrictions.
Documentation: For air shipments, include a note on the air waybill stating the presence and weight of dry ice. When shipping dry ice with dangerous goods, include a shipper’s declaration.
Packing Process
Pre condition containers: Chill insulated boxes or shippers before adding dry ice to reduce initial sublimation.
Layer correctly: Place dry ice above the product so cold air can sink and envelop the shipment. If using multiple formats, place pellets or sheets near the product and blocks further away.
Secure the payload: Use cardboard inserts or foam spacers to prevent movement as dry ice sublimates.
Leave vents open: Do not tape or seal vent holes in insulated containers.
Check carrier policies: Not all carriers accept dry ice; verify guidelines with FedEx, DHL or other providers.
Example: A seafood exporter shipping frozen salmon to Asia packs the fish in polystyrene boxes with vents, inserts 33 lb of dry ice for a 48 hour journey and labels the box with UN 1845 and net weight. The company includes an air waybill noting the presence of dry ice and uses a data logger to record temperatures. The shipment arrives fully frozen, and regulators approve the documentation.
Innovations Shaping Long Lasting Dry Ice Packs in 2025
The cold chain industry is evolving rapidly. Innovations in materials, sensors and packaging are improving safety, efficiency and sustainability. Here’s what’s new in 2025.
Sustainable Materials and Recycling
Manufacturers are investing in plant based foams, recycled polyester and biodegradable fabrics for dry ice pack shells. These eco-friendly materials reduce waste and appeal to environmentally conscious consumers. Reusable dry ice packs also minimize single use plastic waste and offer long-term cost savings.
Growth of Insulated Shipping Boxes
Demand for temperature controlled packaging is booming. The insulated shipping boxes market is expected to grow from USD 3.8 billion in 2025 to USD 8.5 billion by 2035, an 8.5 % compound annual growth rate. This growth is driven by sectors such as food, pharmaceuticals and e commerce that require durable, reusable and sustainable packaging solutions. Vacuum insulated panels and shock resistant designs improve thermal performance and reduce the dry ice needed.
Smart Sensors and IoT Monitoring
Cold chain operators are deploying IoT-enabled sensors and RFID tags that provide real time temperature and humidity data. These sensors alert shippers when temperatures deviate from the required range, enabling corrective action. Some dry ice pack manufacturers embed built in temperature indicators that change color if the pack warms above a set threshold. AI algorithms analyze sensor data to optimize dry ice quantity and adjust packing based on predicted environmental conditions.
Automation and Customization
Advances in manufacturing enable automated filling and precise dosing of dry ice into pack sheets. Customizable sizes and shapes allow companies to match dry ice packs to specific containers, reducing void space and improving efficiency. Augmented reality training tools simulate dry ice handling scenarios, increasing employee awareness of hazards.
AI Integration and Sustainability Initiatives
Looking beyond 2025, AI will optimize dry ice usage, ensuring shipments contain the ideal amount of cooling material based on real time data. Manufacturers are exploring methods to reduce the carbon footprint of dry ice production and to recover CO₂ for reuse. Combining renewable energy for CO₂ capture with automated production could make dry ice more sustainable and affordable.
2025 Latest Developments and Trends
The long lasting dry ice pack industry is at the intersection of technology, sustainability and market demand. Here are some notable trends:
CO₂ supply constraints and market growth: Dry ice demand is increasing about 5 % per year, but CO₂ supply has grown only 0.5 % annually, causing periodic shortages and price volatility. Despite this, the global dry ice market is projected to rise from USD 1.54 billion in 2024 to USD 2.73 billion by 2032.
Hybrid cooling solutions: Shippers are layering dry ice with gel packs and PCMs to reduce reliance on dry ice during supply crunches, improving sustainability. Improved insulation and vacuum panels further reduce dry ice usage.
Sector specific innovations: Meat processors are using thinner dry ice slices and pellets for rapid cooling; pharmaceutical companies are adopting barrier technologies to prevent supercooling and integrating real time monitoring. Industrial users are investing in local pelletizing equipment to ensure supply.
Regulatory focus on sustainability: Governments and carriers are tightening rules on waste and emissions. Carriers may limit dry ice shipments, pushing companies toward reusable and eco friendly alternatives.
Market expansion of reusable dry ice packs: Businesses are adopting reusable dry ice packs for cost savings and environmental benefits. New designs offer longer cooling duration (up to 72 hours) and durability for multiple cycles.
Frequently Asked Questions
Question 1: How long does a long lasting dry ice pack keep items frozen?
A well packed long lasting dry ice pack can maintain freezing temperatures for 24 to 72 hours, depending on the amount of dry ice, insulation quality, ambient conditions and container design. Follow the table above to estimate your needs and always include a safety margin.
Question 2: Can I reuse a dry ice pack?
Most dry ice packs are single use because once the dry ice sublimates, the pack loses its cooling power. However, reusable versions exist where you can refill the pack with dry ice or use durable shells designed for multiple cycles.
Question 3: Is shipping with dry ice allowed on all carriers?
No. FedEx and DHL accept dry ice shipments, but some carriers, such as UPS or the U.S. Postal Service, have restrictive policies. Always check carrier guidelines before shipping and ensure you comply with labeling and documentation requirements.
Question 4: How do I prevent product movement as dry ice sublimates?
Use cardboard inserts or foam spacers to secure items inside the container. As dry ice diminishes, the internal volume changes, so securing your payload prevents damage.
Question 5: What should I do with leftover dry ice?
Let dry ice sublimate in a well ventilated area; never dispose of it in trash bins, sinks or toilets. Do not use hot water to accelerate sublimation, as rapid gas release can cause frostbite or pressure buildup.
Summary and Recommendations
Summary: A long lasting dry ice pack is a powerful tool for maintaining ultra low temperatures without moisture, making it ideal for frozen shipments. Dry ice sublimates directly into gas, absorbing heat and delivering cooling capacity far beyond traditional ice or gel packs. Properly sizing the dry ice pack to your shipment and using high quality insulation ensures hold times of 24 to 72 hours. However, dry ice is a hazardous material (UN 1845) and requires careful handling, vented packaging and compliance with labeling requirements. Innovations in sustainable materials, IoT monitoring and automation are making dry ice packs safer and more efficient.
Actionable Next Steps:
Assess your shipping needs: Determine whether your products require frozen (−20 °C) or chilled (2–8 °C) conditions and select the appropriate refrigerant.
Calculate dry ice quantity: Use the formula and table provided to estimate the amount of dry ice needed and adjust for transit time and ambient conditions.
Invest in quality insulation: Choose insulated boxes with low thermal conductivity and pre chill them to prolong the life of your dry ice.
Comply with regulations: Train staff on hazardous material handling, ensure packages vent properly and include required markings and documents.
Explore innovations: Consider using reusable dry ice packs with smart sensors for real time monitoring and sustainability benefits.
Stay informed: Monitor market trends and supply constraints to adjust your logistics strategies as demand and regulations evolve.
About Tempk
At Tempk, we specialize in advanced cold chain solutions that help you deliver perishable goods safely and sustainably. Our long lasting dry ice packs are engineered to maintain ultra low temperatures for up to 72 hours while using eco friendly materials and smart sensor options. We also offer reusable options to reduce waste and operational costs. With decades of experience in cold chain logistics and a commitment to innovation, we support clients in food, pharmaceutical, and biotech industries worldwide. Contact us to learn how our solutions can optimize your shipments.
Call to Action: Ready to enhance your cold chain? Reach out to our experts today for personalized recommendations on long lasting dry ice packs and other cooling solutions.
