Reliable cold chain logistics keep vaccines, seafood and other perishables safe. 24 hour dry ice packs provide ultra cold temperatures without messy meltwater by using solid carbon dioxide that sublimates directly to gas. In this guide you’ll learn how these packs work, how to size and pack them for your shipment, why they outperform gel packs, and what 2025 trends are shaping sustainable cold chain operations. Whether you’re shipping life saving medicine or premium steaks, this article speaks directly to you, explaining complex concepts in plain language while offering practical tips and a clear action plan.
Understand how 24 hour dry ice packs maintain sub zero temperatures for up to 24 – 72 hours by harnessing sublimation.
Calculate the right weight of dry ice for your product and transit time using simple ratios and tables.
Compare dry ice packs with gel packs to decide which cooling method best fits your situation.
Follow safety and regulatory guidelines to protect people and comply with transportation rules.
Adopt sustainable practices and explore 2025 innovations like smart sensors, blockchain traceability, reusable packs and hybrid cooling.
What Is a 24 Hour Dry Ice Pack and How Does It Work?
24 hour dry ice packs are self contained pouches filled with pellets or slices of solid carbon dioxide (CO₂) that absorb heat by sublimating directly from solid to gas. Unlike water based gel packs that melt and leak, dry ice sublimation occurs at about –78.5 °C, providing extremely low temperatures without creating puddles. The sealed, vented packaging allows CO₂ gas to escape safely while keeping the ice contained. Because the gas is heavier than air, packs should be placed above your goods so cold air can sink down and envelop the shipment.
Understanding Sublimation: Why Dry Ice Doesn’t Melt
Sublimation is the process by which a substance transitions directly from solid to gas without becoming liquid. Dry ice sublimates at –78.5 °C, absorbing a large amount of heat and therefore maintaining ultra cold conditions. There is no meltwater, so your products stay dry and free from condensation. This makes dry ice packs perfect for shipments of frozen meat, seafood, vaccines or biologic samples that must remain below zero without moisture damage. In contrast, gel packs thaw around 2 – 8 °C and leave behind water.
Comparison of Cooling Methods
| Cooling method | Temperature range | Typical duration | What it means for you |
| Mini dry ice sheet | –78.5 °C to –18 °C | 24 – 48 hours | Ideal for pharmaceuticals or biologics requiring ultra low temperatures; prevents moisture. |
| Disposable dry ice pack | Around –78.5 °C | Up to 72 hours | Maintains frozen meats, seafood or vaccines; no meltwater, but single use. |
| Gel pack | 2 – 8 °C | Up to 48 hours | Suitable for chilled items like produce and medicines; reusable but may leak. |
| Traditional water pack | ≈ 0 °C | 24 – 36 hours | Cheapest option for short journeys; limited cooling and produces meltwater. |
As the table shows, dry ice packs deliver the coldest temperatures and longest duration without moisture. While gel or water packs suffice for chilled goods, dry ice is unmatched for deep freeze requirements.
Real World Application and Benefits
When shipping frozen goods like vaccines, dry ice packs absorb heat as the CO₂ changes state, maintaining –78.5 °C for up to three days. Gel packs, by contrast, maintain 2 – 8 °C and eventually melt. Because dry ice releases no liquid, packaging stays dry and hygienic, making it ideal for sensitive products such as biologic samples or seafood. In short, dry ice packs keep your payload colder and cleaner for longer.
Practical Tips for Using Dry Ice Packs
Hydrate and freeze properly: If using dry ice sheets that require activation, hydrate the polymer cells and freeze them for at least 24 hours.
Pre chill your products: Freezing or chilling goods before packing reduces the initial heat load and extends cooling duration.
Use larger packs for longer trips: Bigger dry ice packs contain more CO₂ and last longer.
Position packs above your goods: Cold air sinks, so placing the dry ice on top ensures effective cooling; for longer routes, surround goods with packs and combine with phase change materials (PCMs).
Monitor temperature: Employ data loggers or IoT sensors to track internal temperatures and adjust the number of packs accordingly.
Actual case: A pharmaceutical company shipped 8 lb of frozen vaccine vials from Los Angeles to Chicago using an 8 lb dry ice pack and added 30 % extra to compensate for summer heat. By pre freezing the vials to –20 °C and using vacuum insulated panels, the shipment stayed below –70 °C for 72 hours.
Sizing and Packing: How Much Dry Ice Do You Need?
Determining the right amount of dry ice is critical. Under packing leads to thawing, while over packing increases cost and risk. The amount depends on product weight, transit time, insulation quality and ambient temperature. An easy guideline is the 1:1 ratio – equal weight of dry ice to product weight for shipments up to 48 hours. For 24 hour shipments you may use slightly less, but it’s wise to add extra in hot weather or complex routes. For journeys longer than two days, a 1.5:1 ratio is recommended.
Dry Ice Calculator: Estimating Weight Needs
Use the following table to estimate how much dry ice you need based on payload weight and duration. The values assume good insulation and represent total dry ice weight placed above (and sometimes below) the load:
| Payload weight (lb) | Dry ice for <12 h (lb) | Dry ice for 24 – 48 h (lb) | Dry ice for 48 – 72 h (lb) | Practical meaning |
| 5 | 3 | 5 | 10 | A 5 lb payload needs about 5 lb of dry ice for a day; double for longer trips. |
| 10 | 5 | 10 | 15 | Use a 1:1 ratio (10 lb) for up to two days, and 1.5:1 for 72 hours. |
| 15 | 8 | 15 | 23 | Add extra for mid size loads; ensure venting when using >20 lb. |
| 20 | 10 | 20 | 30 | Larger cargo needs proportionally more dry ice to stay frozen over long distances. |
| 30 | 10 (top) + 5 (bottom) | 20 (top) + 10 (bottom) | 30 (top) + 15 (bottom) | Splitting dry ice between top and bottom ensures uniform cooling for heavy shipments. |
| 40 | 15 (top) + 5 (bottom) | 25 (top) + 15 (bottom) | 40 (top) + 20 (bottom) | Heavy freight may require up to 40 lb for 72 hours; plan for handling and regulatory limits. |
Additional Sizing Tips
Assess product requirements: Decide whether your goods must stay at –70 °C, –20 °C or 2 – 8 °C, and adjust dry ice accordingly.
Consider route complexity: Add 10 – 15 % more dry ice for multi hand off routes or potential delays.
Upgrade insulation: Vacuum insulated panels or reflective liners can reduce dry ice requirements by up to 25 %.
Use hybrid packouts: Combining dry ice with PCMs buffers temperature swings and extends cooling beyond 72 hours.
Precondition and pre freeze: Chilling products and packaging before assembly lowers the initial heat load.
Real world tip: A seafood exporter replaced water ice with small dry ice slices and vented boxes. By matching dry ice weight to product weight and filling voids, they reduced shipment weight by 30 % and kept fish fillets frozen for 48 hours without leaks.
Interactive Element – Dry Ice Weight Calculator
For reader engagement, embed a simple weight calculator that lets users input payload weight, transit time and ambient conditions to estimate the required dry ice. Such interactive tools increase dwell time and help users apply the information immediately.
Dry Ice Packs vs Gel Packs: Which Should You Choose?
Deciding between dry ice packs and gel packs comes down to required temperature, product sensitivity, cost and handling considerations. Dry ice packs maintain –78.5 °C and are suited for frozen goods; gel packs maintain 2 – 8 °C and are best for chilled products.
Pros and Cons of Gel Packs vs Dry Ice Packs
| Attribute | Gel packs | Dry ice packs | Meaning for you |
| Temperature range | Near 0 °C | Around –78.5 °C | Use gel packs for chilled items and dry ice packs for frozen goods. |
| Duration | 12 – 24 hours (standard) | 12 – 24 hours per pack; longer with blocks | Dry ice lasts longer in insulated containers. |
| Residue | Melts to water | Sublimates to gas | Dry ice prevents soggy packages and condensation. |
| Handling | Non hazardous | Requires gloves and venting | Dry ice demands training; gel packs are easier. |
| Regulation | Not regulated | Class 9 hazardous material | You must follow packaging, labeling and transport rules for dry ice. |
When to Choose Each Cooling Method
Frozen goods (meat, seafood, vaccines): Choose dry ice packs to maintain ultra low temperatures.
Chilled goods (produce, chocolate, pharmaceuticals): Use gel packs to keep items between 2 – 8 °C and prevent freezing.
Mixed shipments (meal kits): Separate compartments; place dry ice around frozen items and gel packs near chilled items.
Customer experience: If customers are unfamiliar with dry ice, gel packs may be safer and simpler; always include clear instructions when shipping with dry ice.
Handling Safety and Regulatory Considerations
Dry ice is extremely cold and classified as a hazardous material (UN 1845). Proper handling is essential to protect workers and customers:
Wear protective gear: Use thick gloves, safety goggles and long sleeves to prevent frostbite.
Vent containers: Never seal dry ice in an airtight box; use vented lids or punch small holes to prevent pressure buildup and CO₂ accumulation.
Label and document: Mark packages with UN 1845 labels and indicate the net weight to comply with regulations.
Provide instructions: Inform recipients about dry ice handling and disposal to reduce risk of injury.
Respond to frostbite: If contact occurs, remove clothing not frozen to the skin and immerse the area in warm (not hot) water.
Regulations limit how much dry ice you can ship. Non medical shipments containing more than 5.5 lb (2.5 kg) must comply with Title 49 of the Code of Federal Regulations (CFR) or International Air Transport Association (IATA) rules. Many airlines cap dry ice at 5.5 lb per package, and packages must be vented and labeled. Gel packs, meanwhile, are unregulated and require no special labels.
Safety Checklist for Dry Ice Shipping
| Safety measure | Description | Why it matters |
| Wear protective gear | Use thick gloves, goggles and long sleeves | Prevents frostbite and eye injury. |
| Vent containers | Use vented lids or punch small holes | Prevents pressure buildup and CO₂ accumulation. |
| Label and document | Mark packages with UN 1845 and net weight | Ensures compliance with shipping regulations. |
| Provide instructions | Include handling and disposal instructions | Reduces risk of injury and enhances user experience. |
| Respond to frostbite | Immerse affected area in warm water | Promotes proper first aid and minimises damage. |
Tip for delicate shipments: When shipping pharmaceuticals that must remain within 2 – 8 °C, choose gel packs or PCMs, or separate them from dry ice using insulated partitions. The U.S. Food and Drug Administration (FDA) requires that injectable medicines be kept within this temperature range.
Environmental Impact and Sustainability
Dry ice is essentially recycled CO₂ captured from industrial processes like ammonia synthesis or ethanol production. Using dry ice repurposes carbon dioxide that would otherwise be vented, but the sublimated gas still enters the atmosphere. Sustainability therefore depends on minimising dry ice consumption and improving insulation. Here are key practices:
Source recycled CO₂: Choose suppliers that produce dry ice from captured industrial CO₂ to reduce reliance on virgin fossil fuels.
Optimise pack quantity: Use just enough dry ice by calculating needs and upgrading insulation, which cuts both cost and emissions.
Combine cooling methods: Hybrid packouts that combine dry ice with PCMs or gel packs extend cooling without adding more CO₂.
Consider reusable packs: Emerging reusable dry ice packs can be refilled hundreds of times, cutting waste and long term costs by up to 20 %.
Educate customers: Provide clear disposal instructions so recipients allow dry ice to sublimate outdoors, preventing damage or harm.
Sustainability Measures and Benefits
| Sustainability measure | Description | Benefit |
| Recycled CO₂ production | Dry ice produced from CO₂ captured during industrial processes | Reduces reliance on virgin fossil fuels and lowers carbon footprint. |
| Insulation upgrades | Use vacuum panels, reflective liners or foam fillers | Lowers dry ice consumption and CO₂ release. |
| Hybrid cooling systems | Combine dry ice with PCMs or gel packs | Extends cooling duration without adding more dry ice. |
| Reusable dry ice packs | Packs designed to be refilled and reused hundreds of times | Cuts waste and long term costs by up to 20 %. |
From Reusable Dry Ice Packs to Smart Sensors
Reusable dry ice packs are revolutionising cold chain logistics. Because they can be replenished, businesses save money and reduce waste while maintaining ultra cold conditions. Compared with traditional gel or water packs, reusable dry ice packs offer superior temperature stability, zero water damage and compact storage. Companies that switch to reusable packs report up to a 20 % reduction in cooling costs within six months. In 2025 these packs incorporate biodegradable coatings to minimise environmental impact and smart sensors to monitor temperature in real time. Integrating phase change materials (PCMs) and vacuum insulation panels (VIPs) further extends cooling duration while reducing the required quantity of dry ice.
2025 Trends and Innovations Shaping Dry Ice Packs
The cold chain industry is evolving rapidly. In 2025, dry ice packs benefit from technological and sustainability innovations that improve performance and reduce environmental impact. Here are the key trends:
Smart Monitoring and IoT Sensors
Internet of Things (IoT) devices and smart sensors allow real time monitoring of temperature, humidity and vibration in shipments. They provide comprehensive visibility into the supply chain, enabling logistics teams to act quickly if temperatures deviate. Predictive analytics based on sensor data help anticipate potential irregularities and allow proactive measures to prevent spoilage.
Blockchain for Traceability
Blockchain is a decentralised digital ledger that records every transaction and handoff in the supply chain. Each block is linked chronologically, creating an immutable record that enhances security, transparency and traceability. When combined with predictive analytics, blockchain ensures accurate delivery forecasts and reduces disputes.
Advanced Refrigeration and Packaging Technologies
Energy efficient refrigeration systems reduce electricity consumption and use eco friendly refrigerants. Temperature controlled packaging innovations include phase change materials (PCMs) that absorb and release thermal energy to stabilise internal temperature, vacuum insulation panels (VIPs) that minimise heat transfer, aerogels with porous structures that provide exceptional thermal insulation, and eutectic plates that offer reusable cooling for extended periods. Dry ice remains crucial for ultra cold shipments but must be handled carefully.
Reusable Packs and Sustainable Coatings
Reusable dry ice packs with biodegradable coatings reduce waste and align with corporate sustainability goals. These packs incorporate smart sensors for temperature monitoring and offer flexible configurations for various shipment requirements.
Hybrid Cooling Systems
Hybrid solutions combine dry ice with PCMs and gel packs to create multi temperature compartments in a single shipment. This approach extends cooling duration and reduces the amount of dry ice needed, lowering CO₂ emissions and cost.
Market Insights and Supply Challenges
The global cold chain refrigerants market is projected to grow from about US$1.69 billion in 2025 to US$2.92 billion by 2032. Meanwhile, the global dry ice market was valued at US$1.54 billion in 2024 and is expected to reach US$2.73 billion by 2032, a compound annual growth rate of 7.4 %. This growth is fueled by food shipping, vaccines and industrial applications. However, dry ice consumption has been rising at roughly 5 % per year while CO₂ supply grows only 0.5 %, leading to periodic shortages and price volatility. Manufacturers respond by building local CO₂ production hubs and capturing CO₂ from bioethanol plants. Shippers mitigate shortages by blending dry ice with PCMs and improving insulation to stretch each pound further.
Future Trends
Looking forward, expect greater adoption of GPS and artificial intelligence (AI) for precise location tracking and predictive logistics. Drones and autonomous vehicles will play a larger role in delivering temperature sensitive goods quickly and efficiently. Robotics and automation will enhance order fulfillment and reduce labour shortages. The supply chain will continue to prioritise sustainability, with route optimisation, eco friendly refrigerants and recyclable packaging reducing carbon footprints.
Frequently Asked Questions (FAQ)
Q1: How long do 24 hour dry ice packs actually last?
Dry ice sublimates at about 5 – 10 lb per 24 hours in a well insulated container. A standard 24 hour pack is designed to keep goods frozen for at least a full day, but larger packs or blocks can extend the duration up to 72 hours.
Q2: How much dry ice should I use for a 24 hour shipment?
A general rule is to use equal weight of dry ice to product weight for shipments under 48 hours. For example, a 10 lb payload may require 5 – 10 lb of dry ice. Adjust upward for hot weather or poor insulation.
Q3: Are dry ice packs safe to use?
Yes, when handled properly. Always wear insulated gloves, vent containers and label packages with the UN 1845 hazard warning. Comply with weight limits and transport regulations; non medical shipments containing more than 5.5 lb must follow Title 49 CFR or IATA rules.
Q4: Can I reuse a dry ice pack?
Traditional disposable packs are single use. However, reusable dry ice packs are emerging that can be refilled hundreds of times, reducing waste and saving money. In 2025 these packs often feature biodegradable coatings and smart sensors.
Q5: What’s the difference between dry ice and gel packs for overnight shipping?
Dry ice maintains –78.5 °C and keeps products frozen; gel packs maintain 2 – 8 °C and are suited for chilled goods. Dry ice is regulated as a hazardous material and requires venting and labeling, while gel packs are non hazardous and easier to handle.
Summary and Recommendations
Key Takeaways
Dry ice packs provide ultra cold, moisture free cooling by sublimating solid CO₂ at –78.5 °C.
Sizing is crucial: use a 1:1 dry ice to product weight ratio for 24 – 48 hour shipments and increase to 1.5:1 for longer journeys.
Gel packs are best for chilled goods, while dry ice packs suit frozen items; hybrid packouts can serve mixed shipments.
Safety matters: wear protective gear, vent containers, label packages and follow regulations on weight limits.
Sustainability and innovation are reshaping the industry: reusable dry ice packs, smart sensors, hybrid cooling and blockchain traceability all improve efficiency and reduce waste.
Actionable Next Steps
Assess your product requirements: Identify whether your goods need to stay frozen or simply chilled. This determines whether to use dry ice, gel packs or a hybrid solution.
Calculate your dry ice needs: Use the provided weight table and consider transit time, insulation quality and ambient temperature. Add a 10 – 15 % buffer for potential delays.
Upgrade insulation and monitor temperature: Invest in vacuum insulated panels, reflective liners or PCMs to reduce dry ice usage, and use IoT sensors or data loggers for real time monitoring.
Implement safe handling protocols: Train staff to use protective gear, vent containers and properly label shipments. Provide clear instructions to customers to avoid accidents.
Explore reusable and sustainable options: Consider reusable dry ice packs with smart sensors and biodegradable coatings, and combine cooling methods to extend duration while lowering environmental impact.
About Tempk
Tempk specialises in innovative cold chain packaging and offers a comprehensive range of dry ice packs, gel packs, insulated bags and high performance box liners. Our products use recycled CO₂ and advanced insulation to deliver reliable, eco friendly cooling. Backed by decades of experience and a dedicated R&D center, we provide tailored solutions that help you ship perishable goods safely while cutting waste and cost. Partnering with Tempk gives you access to state of the art technology, technical support and industry leading sustainability practices.
Call to Action: Ready to optimise your cold chain? Contact Tempk today for a personalised consultation. Our team will help you choose the right products, calculate your dry ice requirements and implement sustainable practices for 2025 and beyond.
