Cold Chain

Published July 15, 2020

Cold chain refers to the temperature-controlled supply chain used to transport and store perishable goods — pharmaceuticals, food, beverages, chemicals, and biological materials — within a specified temperature range from origin to end destination. Maintaining the cold chain means that refrigerated or frozen conditions are continuously preserved throughout every stage: manufacturing, warehousing, transportation, and final delivery.

Cold Chain Temperature Ranges

• Frozen: -18°C (0°F) or below — ice cream, frozen food, some biologics
• Refrigerated (chilled): 2°C to 8°C (36°F to 46°F) — fresh produce, dairy, most pharmaceuticals
• Controlled Room Temperature (CRT): 15°C to 25°C (59°F to 77°F) — some medications, cosmetics
• Cryogenic: Below -150°C (-238°F) — certain biological samples and specialized materials

Cold Chain Shipping Modes

Temperature-controlled shipping uses specialized equipment at every stage: refrigerated warehouses, reefer (refrigerated) trucks and trailers, insulated packaging with dry ice or gel packs for parcel shipments, and temperature-controlled aircraft holds for air freight. Each mode shift — for example, from refrigerated truck to air freight — is a critical control point where temperature excursions are most likely to occur.

Cold Chain and Parcel Shipping

For pharmaceutical and specialty food companies using parcel carriers (UPS, FedEx) for direct-to-consumer cold chain delivery, packaging validation is critical. Shippers must qualify their insulated packaging systems — typically using time/temperature studies — to prove the packaging maintains required temperatures through worst-case transit times and ambient temperature extremes. Carrier-certified packaging programs (like UPS Temperature True and FedEx Custom Critical) offer validated packaging solutions but at significant per-shipment cost premiums.