Reefer meaning: what a reefer container is

“Reefer” is short for refrigerated, and in shipping a reefer is a refrigerated container: a standard-size box with insulated walls and its own refrigeration unit, which holds cargo at a set temperature for as long as it has power. The word can also mean a refrigerated ship or truck, but on a booking or a bill of lading it means the container.

A reefer is not a cool box that keeps cold in. It is a machine that removes heat, and it needs power for the whole journey: from a plug at the terminal, from the ship’s sockets at sea, and from a generator set on the road. For fresh produce the usual box is the 40ft high cube, with roughly 67 m³ inside against about 76 m³ in a dry box of the same size, because the insulation and the machinery take the difference.

What it controls #

The temperature, held to a setpoint fixed before loading. The fresh air exchange, which lets respiring fruit vent carbon dioxide and ethylene. Humidity on units that support it, and the atmosphere itself on a controlled atmosphere booking. Each of these is a commercial decision made at booking, and none can be put right at destination.

Every reefer also logs its own temperatures through the voyage. That log is the single most useful document in a quality dispute, so download it on arrival as routine, before the empty goes back.

Why reefers cost more to be late with #

Two things compound. Free time on a reefer is typically 2–4 days at destination against 5–7 for dry cargo, and the daily demurrage and detention rates are higher, because the equipment is scarcer and more expensive. The cargo that can least afford to wait runs on the shortest clock.

One more trap: the container number, four letters and seven digits under ISO 6346, identifies the physical box, not your consignment. The line reuses the box for years, so the same number turns up on many unrelated shipments. The bill of lading number is what identifies your cargo with the carrier.

What is a reefer container? covers the sizes and internal dimensions, setpoints, controlled atmosphere and the failures that cause most claims.

FAQ #

What does reefer mean in shipping? #

Reefer is short for refrigerated. It usually means a reefer container, a shipping container with its own refrigeration unit, and sometimes a refrigerated ship or trailer. Reefer cargo is anything that travels in one: fresh produce, meat, fish, dairy or pharmaceuticals.

Why is reefer free time shorter than dry? #

Because the equipment is scarcer, more expensive and in constant demand. Lines price the box’s time accordingly, which is why the cargo with the least tolerance for delay runs on the shortest clock.

Does a reefer keep working if it loses power? #

No. It holds temperature for a while through insulation and the cold of the load itself, but an extended unplugged period, such as a wait for a plug at a busy terminal, is a genuine cold-chain risk.