Insulated Container
An Insulated Container is a container built with insulated walls, floor and roof that slow the transfer of heat between inside and outside, keeping the cargo's temperature stable for longer. Unlike a reefer, a basic insulated container (a conair or porthole container) has no built-in refrigeration unit of its own — it either relies purely on insulation to protect cargo over shorter journeys, or is fed cold air from an external clip-on or ship-based cooling system.
Insulated containers suit cargo that must be protected from temperature swings but does not need active freezing — certain foodstuffs, pharmaceuticals and sensitive goods — and can be cheaper to run than a fully refrigerated unit where external cooling is available. The distinction between insulated (passive) and refrigerated (active) equipment matters when planning cold-chain shipments and matching the right box to the cargo and route.
Not every temperature-sensitive shipment needs a full reefer — sometimes insulation, or insulation plus external cooling, is enough and cheaper. Knowing the difference between passive insulated and active refrigerated containers lets a shipper match the right (and right-priced) equipment to the cargo and journey, a real cold-chain planning decision.
What is the difference between an insulated and a refrigerated container?
An insulated container only slows heat transfer and has no cooling unit of its own; a refrigerated container (reefer) actively cools with a built-in refrigeration unit.
When is an insulated container used?
For cargo that must be shielded from temperature swings but not actively frozen, or where external cooling is supplied to the box.