How to Handle Hazmat Dry Ice Pack Sheets for Compliant Shipping
Shipping with dry ice is a balancing act between keeping your product frozen and staying within regulatory limits. A hazmat dry ice pack sheet—thin panels of solid carbon dioxide—keeps cargo around –78.5 °C for up to 72 horas, but it is classified as a hazardous material. You need to pack, label and vent your box correctly to protect handlers and avoid fines. This guide demystifies hazmat dry ice pack sheets, explains regulations such as UN 1845 y AQUÍ PI 954, and shows how to calculate the right amount of dry ice for 24–72 hour shipments.
What is a hazmat dry ice pack sheet and how does it differ from pellets or gel packs?
Which regulations apply when shipping with dry ice in 2025, and how do you label packages correctly?
How much dry ice should you use for different payloads and transit times?
What best practices keep shipments safe, efficient and sustainable?
Cual 2025 trends are reshaping cold chain shipping, from smart sensors to reusable pack sheets?
What Are Hazmat Dry Ice Pack Sheets and Why Are They Used?
Hazmat dry ice pack sheets are flexible panels made from compressed CO₂. Each cell in the sheet contains a small quantity of dry ice or a hydrated blend that is frozen to –78.5 °C. When you activate the sheet (often by folding along perforations), it releases extreme cold as the CO₂ sublimates directly from solid to gas. Pack sheets are widely used because they keep goods frozen for up to 72 horas, leave no liquid residue and can be arranged easily around oddly shaped products. Compared with dry ice pellets, which cool quickly but sublimate within 24–48 hours, pack sheets maintain a steadier temperature profile and are less messy to handle.
The “hazmat” label stems from the material’s classification. In transportation regulations, dry ice is listed as Dióxido de carbono, Sólido (Hielo seco), Y 1845 and falls under Clase 9 miscellaneous dangerous goods. Its hazard arises from two factors:
Frío extremo: direct contact can cause frostbite and damage products. Protective gloves and goggles are mandatory when handling pack sheets.
liberación de gas: as dry ice sublimates, it produces carbon dioxide gas. In sealed spaces this can displace oxygen and build pressure, which is why packages must have vents or breathable insulation.
Dry ice pack sheets are preferred in food, pharmaceutical and biotech shipping because they provide ultra cold temperatures without moisture. Por ejemplo, meal kit companies use mini pack sheets to keep meat frozen, and mRNA vaccines require –70 °C conditions to maintain efficacy. The sheets’ flexibility lets you wrap or layer them for surround or hybrid pack outs, improving hold time and distribution of cold.
Dry Ice Pack Sheets vs Pellets vs Gel Packs
Choosing the right cooling medium requires understanding how different formats perform. The table below compares dry ice pack sheets with pellets, gel packs and phase change materials (PCM). Use it to match your shipment’s temperature requirements and hazard considerations.
| Método de enfriamiento | Rango de temperatura & Duración | Beneficios prácticos & Hazmat Considerations |
| Hojas de paquete de hielo seco | –29 °C to –40 °C for 36–72 hours | Flexible sheet format offers steady cold and longer hold than pellets; easier to separate from product; still subject to Class 9 hazard classification and must be vented and labeled. |
| Pellets de hielo seco | –78.5 °C for 24–48 hours | Rapid cooling and precise control; ideal for pharmaceuticals and biotech samples; high surface area causes faster sublimation and requires more frequent replenishment; hazard label and ventilation mandatory. |
| Paquetes de gel | 0 °C to –20 °C for 12–24 hours | Non hazardous and reusable; no special labeling required; Adecuado para bienes refrigerados, no congelado; produce meltwater that may damage packaging. |
| Materiales de cambio de fase (PCM) | Personalizable (–70 °C to +8 °C) for 24–96 hours | Tailored to specific temperature bands; often used in combination with dry ice to reduce CO₂ usage; generally non hazardous but require careful handling to avoid leaks. |
User Tip: For shipments longer than 48 horas, hybrid solutions combining pack sheets with PCMs and a small amount of pellets can extend hold time and reduce CO₂ consumption.
Estudio de caso: A meat exporter needed to keep 20 kg of beef frozen during a 48 hour flight from California to Japan. The company used four 24 cell pack sheets above and below the product, pre chilled the EPS container and added 3 kg of pellets on top. Vent holes allowed CO₂ gas to escape. Temperature sensors showed the meat stayed below –18 °C for 48 horas, and packaging waste fell by 60 % compared with using pellets alone.
Hazmat Classification and Regulatory Requirements
Shipping dry ice pack sheets is not like sending a standard gel pack. Dry ice is a regulated hazardous material because its sublimation can pressurize sealed containers and displace oxygen. The regulatory framework includes U.S. Departamento de Transporte (PUNTO) normas, La Asociación Internacional de Transporte Aéreo (IATA) and postal regulations such as USPS Packaging Instruction 9A. Failure to comply can lead to fines or shipment delays.
Clasificación: Dióxido de carbono, Sólido (Y 1845)
All shipments containing dry ice must be declared under the proper shipping name "Hielo seco" o "dióxido de carbono, Sólido" with identification number Y 1845. Hazmat University notes that dry ice is regulated in air and vessel modes but is not regulated by ground transport within the United States—provided you follow minimum packaging requirements of 49 CFR 173.217.
Requisitos de embalaje
El hielo seco libera gas CO₂ al sublimarse. Packaging must therefore allow gas to escape to prevent rupture:
Use vented containers. Do not place dry ice in airtight plastic bags or sealed metal drums. Mercury Shipping advises using good quality fiberboard, plastic or wooden boxes with an inner layer of Styrofoam insulation that is no hermético. The outer box must be robust enough to withstand transport stresses.
Insulate appropriately. Pack sheets perform best in insulated containers. EPS foam is affordable but has higher sublimation rates; poliuretano (Puro) improves hold time; vacuum insulated panels (personaje) dramatically reduce CO₂ needed.
Secure the payload. Cushion the product with bubble wrap or foam inserts to minimize void space and prevent shifting. Minimizing warm air pockets reduces sublimation.
Buffer layers. Place a cardboard or foam buffer between pack sheets and the product to prevent direct contact and freezer burn.
Marking and Labeling
Proper labeling ensures that carriers and emergency personnel recognize the hazard:
Identify the material. Mark the package on the same surface as the hazard label with “Dry Ice” or “Carbon Dioxide, Solid” and the UN 1845 number. USPS requires the address side to include the name of the contents being cooled (p.ej., frozen medical specimens) y el peso neto del hielo seco.
Display hazard symbols. Affix a Clase 9 etiqueta de materiales peligrosos to every package. For air transportation, the label must not be written on or modified, and the net weight of dry ice should be entered in the specified area.
Include shipper and consignee information. The names and addresses of the sender and recipient must be durably marked.
Differentiate by mode. USPS requires air shipments to bear the Class 9 label and the designation “Carbon Dioxide Solid, UN 1845,” while surface shipments must be marked “Surface Only” with the same UN number.
Weight Limits and Documentation
Weight limits vary by carrier and transportation mode:
IATA limits: Para aviones de pasajeros, packages may contain up to 2.5 kg de hielo seco; cargo aircraft can carry up to 200 kg por paquete. These limits also apply to pack sheets because the weight of CO₂ content counts toward the total.
Límites de USPS: Each air mailpiece may contain no more than 5 lb (≈ 2.27 kilos) de hielo seco. Surface mail can exceed 5 lb but must be clearly marked as surface only.
Ground shipments: En los Estados Unidos, ground transport of dry ice is largely unregulated, but packaging must comply with minimum venting and marking requirements.
Shipping papers: Air shipments require a completed Shipper’s Declaration for Dangerous Goods. Sin embargo, when dry ice is used to cool non dangerous goods, IATA allows the declaration to be replaced by a note on the air waybill indicating the presence of dry ice. Surface shipments do not require a declaration.
Training and Safety Procedures
People who handle hazmat dry ice shipments must be trained in hazard recognition and emergency response. Hazmat University emphasizes that improper venting can lead to package rupture, and exposure to high levels of CO₂ can cause unconsciousness. Key safety practices include:
Wear insulated gloves and goggles to prevent frostbite and eye injury when handling pack sheets.
Use tongs or handles to avoid skin contact; do not place your head over containers, as CO₂ gas is heavier than air and can accumulate.
Store dry ice in ventilated spaces between –80 °C and –20 °C and rotate stock (first in, first out) to avoid using heavily sublimated sheets.
Educate staff about hazard classes, labeling requirements and emergency procedures for CO₂ exposure.
Calculating and Packing Dry Ice Pack Sheets for 24–72 Hour Shipments
Choosing the right amount of dry ice is crucial: too little and the shipment thaws; too much and you risk exceeding weight limits and incurring unnecessary cost. Several rule of thumb formulas help you plan.
Estimating Dry Ice Quantity
Weight ratio method: Tempcontrolpack recommends a 1:1 ratio of dry ice weight to product weight for 48 hour shipments, with adjustments for seasonal temperature, route complexity and insulation quality. Por ejemplo, envío 10 kg of seafood across a tropical route might require 10 kg of dry ice pack sheets plus a 20 % buffer for high ambient temperatures.
Hourly consumption method: Hazmat guidelines suggest using 5–10 lb (2.3–4.5 kg) de hielo seco por 24 horas for standard insulated boxes and increasing by 15–25 % for weekend or holiday delays. A 72 hour transit might therefore require 15–30 lb of dry ice pack sheets or pellets, with heavier loads allocated to outer edges or top layers.
Product weight vs duration table: The following table adapts a rule of thumb from an insulated packaging expert. It assumes standard EPS insulation and ambient temperatures around 25 °C. Increase quantities by 20–30 % in very hot conditions or when using lightweight insulation.
| Payload Weight | Dry Ice Required (<12 h) | Dry Ice Required (24–48 H) | Dry Ice Required (48–72 h) |
| 5 lb (2.3 kilos) | 3 lb (1.4 kilos) | 5 lb (2.3 kilos) | 10 lb (4.5 kilos) |
| 10 lb (4.5 kilos) | 5 lb (2.3 kilos) | 10 lb (4.5 kilos) | 15 lb (6.8 kilos) |
| 15 lb (6.8 kilos) | 7 lb (3.2 kilos) | 15 lb (6.8 kilos) | 23 lb (10.4 kilos) |
| 20 lb (9 kilos) | 10 lb (4.5 kilos) | 20 lb (9 kilos) | 30 lb (13.6 kilos) |
Packing Strategy: Arriba, Surround or Hybrid?
The way you arrange dry ice pack sheets influences sublimation rates and temperature uniformity:
Top loading: Placing all pack sheets on top of the payload cools from above. Because cold air sinks, this method maximizes downward cooling and is ideal for one way shipments or boxes with limited space. Sin embargo, it may cause uneven distribution if the package is mishandled.
Surround: Position sheets around all sides, mimicking an ice box effect. Surround layouts slow sublimation because the ice surface area is reduced, but they require more dry ice and may add complexity during packing. They are recommended for delicate items that cannot tolerate thermal gradients.
Híbrido: Combine top and surround approaches using multiple thin sheets and phase change materials. Tempcontrolpack’s 2025 guide notes that a hybrid pack out (multiple thin sheets plus PCMs) results in 5–8 % sublimation per day, extending hold time to 48–72 horas. The hybrid method also provides a buffer if the box orientation shifts during transit.
Step by Step Packing Guide
Pre condition everything. Pre chill the product and pre freeze pack sheets to –78.5 °C. Conditioning the insulated box (p.ej., by storing it in a freezer) reduces the initial heat load.
Layer properly. Place a buffer layer between the product and the pack sheets to prevent direct contact. If using a hybrid approach, insert PCMs beneath the top sheets.
Llenar los vacíos. Use foam or bubble wrap to minimize air pockets. A tighter fit reduces sublimation and prevents product shifting.
Ventar la caja. Ensure there are small holes or breathable insulation to allow CO₂ to escape. Do not tape all seams airtight.
Sello y etiqueta. Close the box securely but not hermetically. Affix hazard labels and mark the net quantity of dry ice and contents as required.
Document weight and date. Record the net dry ice weight on the airway bill or shipping papers. This helps carriers confirm that you remain within legal limits and provides traceability.
User Tips for Specific Scenarios
Weekend and holiday shipping: Agregar un 25 % buffer to account for potential delays.
Hot weather routes: Use higher performance insulation like VIPs or PURs, and consider hybrid pack outs to cut sublimation rates by up to 18 %.
Seafood vs vaccines: Seafood typically requires –20 °C; vaccines may require –70 °C. Use pellets on top for rapid cooling of vaccines, and pack sheets around the product for longer hold times.
Reusing pack sheets: Many high quality sheets can be refrozen and reused. Inspect for leaks and integrity before reuse and follow the same venting and labeling procedures.
Real world Example: A dessert brand shipping ice cream across the country switched from using only pellets to a hybrid system of one top dry ice block, a thin pellet blanket and a reflective liner. This change added 10–14 horas of frozen hold time while improving carrier acceptance rates and reducing product damage.
2025 Trends and Innovations in Hazmat Dry Ice Shipping
The cold chain industry is evolving rapidly as supply constraints, sustainability goals and new technologies reshape how we move frozen goods. Staying informed about these trends helps you future proof your shipping strategy.
Market Dynamics and Supply Pressures
Global dry ice consumption is increasing by ≈ 5 % por año, yet CO₂ supply is growing only 0.5 % anualmente. This imbalance leads to periodic price surges—as high as 300 % durante las crisis de suministro. Analysts project the dry ice market to grow from $1.54 mil millones en 2024 a $2.73 mil millones por 2032 (7.4 % Tocón). Mientras tanto, the broader cold chain industry is expected to reach $1.611 billones por 2033 con un 20.1 % compound annual growth rate.
Shippers are diversifying cooling strategies—mixing dry ice with PCMs, using better insulation and signing long term supply contracts—to stretch limited supply. The adoption of onsite pelletizers and local CO₂ capture reduces reliance on remote suppliers and lowers carbon footprints.
Innovations in Packaging and Monitoring
Reusable pack sheets: Manufacturers are developing durable dry ice sheets that can be refrozen multiple times, reducing waste and cost.
Smart sensors and IoT tracking: Real time monitoring devices track temperature, CO₂ levels and sublimation rates, enabling dynamic replenishment and ensuring regulatory compliance.
Sistemas de enfriamiento híbrido: Combining dry ice with PCMs and high performance insulation decreases CO₂ usage by up to 18 % while improving temperature consistency.
CO₂ capture and circular economy: Suppliers are capturing CO₂ from bioethanol and industrial processes, creating a renewable source of dry ice and supporting circular economy initiatives.
Blockchain and transparency: Some cold chain platforms are testing blockchain to track origin, handling conditions and temperature history, boosting trust in food and pharma shipments.
Regulatory updates: 2025 saw clarifications from USPS and IATA: USPS now caps air mail at 5 lb of dry ice per package, while IATA updated Packing Instruction 954 to emphasise venting and documentation requirements. Carriers are implementing checklist driven audits to ensure compliance.
Sector Specific Insights
Alimento & Kits de comida: Eco friendly packaging is a top priority. Consumers prefer recyclable or compostable liners. Meal kit companies use mini dry ice sheets for portion control and to reduce packaging weight.
Biofarmacéuticos: Ultra cold shipments like mRNA vaccines rely on improved barrier technologies and real time monitoring to prevent accidental super cooling.
Industrial Cleaning: Dry ice blasting contractors invest in onsite pelletizers and local supply contracts to secure priority access during supply crunches.
Preguntas frecuentes
Q1: Why is dry ice classified as a hazardous material?
Dry ice is extremely cold and sublimates into carbon dioxide gas. Without proper venting, the gas can build pressure and displace oxygen, endangering handlers and aircraft. Therefore regulators classify it as a Class 9 miscellaneous dangerous good.
Q2: ¿Necesito la declaración de un remitente para hielo seco??
It depends on the cargo and mode. When dry ice is used to cool non dangerous goods, IATA allows you to simply note the presence of dry ice and its weight on the air waybill. If you are cooling dangerous goods or shipping by USPS air, you must complete a Shipper’s Declaration for Dangerous Goods.
Q3: How much dry ice can I include in a package?
Passenger aircraft limit dry ice to 2.5 kg por paquete and cargo aircraft to 200 kg por paquete. USPS air mail caps dry ice at 5 lb (2.27 kilos) por correo. Ground transport has no specified cap but must adhere to venting and marking requirements.
Q4: Can I reuse hazmat dry ice pack sheets?
Sí, many high quality sheets can be refrozen and reused multiple times. Inspect them for leaks or damage and follow the same safety and labeling guidelines.
Q5: What alternatives exist if dry ice is unavailable?
Alternatives include gel packs, which are non hazardous but only maintain 0 °C to –20 °C for 12–24 hours, and phase change materials that can be tuned to the required temperature band for up to 96 horas. Mechanical refrigeration is another option but requires power and is expensive.
Resumen
En 2025, hazmat dry ice pack sheets remain a cornerstone of cold chain shipping. They provide ultra cold temperatures for up to 72 horas, but their hazardous nature demands careful packaging, labeling and training. Follow the UN 1845 y clase 9 requisitos: contenedores ventilados, proper markings and weight limits; use insulated boxes and buffer layers; calculate dry ice quantity using weight ratios and hourly consumption guidelines; and consider hybrid pack outs for longer durations. Stay current with 2025 trends such as smart sensors, reusable pack sheets and CO₂ capture to optimize cost and sustainability.
Pasos de acción:
Assess your product’s temperature requirement and transit duration. Choose between pellets, pack sheets, gel packs or hybrid solutions accordingly.
Select the right container and insulation. Pre condition all components and minimize void space to reduce sublimation.
Calculate dry ice quantity. Use weight ratio and hourly consumption methods, adding a buffer for weekends or extreme weather.
Package and label correctly. Vent your box, use buffer layers, and mark “Dry Ice, UN 1845” with net weight. Attach the Class 9 hazard label and required documentation.
Mantente informado. Monitor regulatory updates, supply conditions and emerging technologies like reusable sheets and smart sensors. Consider long term supply contracts and sustainable CO₂ sources.
Acerca de Templ
Company Overview: Tempk is a global innovator in cold chain packaging. We design and manufacture dry ice pack sheets, pellets and high performance insulation. Nuestra R&D team focuses on eco friendly materials, smart monitoring devices and hybrid cooling systems to help clients comply with regulations and cut carbon footprints. We partner with food, pharmaceutical and biotech companies worldwide.
Llamado a la acción: If you need help choosing or customizing a hazmat dry ice pack sheet solution, consult our experts. We offer free assessments and can design turnkey pack outs that meet your transit time, temperature and regulatory requirements.
