A Reefer Container is an insulated intermodal container with an integrated refrigeration unit, used for cargo requiring temperature control during transport. Carriers offer reefers in 20-foot and 40-foot high-cube formats and code them RF, 40’RH, or 40RF on bookings. The set-point range typically runs from -30°C to +30°C with humidity and ventilation control on most modern units. For chemical cargo the reefer is the right choice for any product where ambient sea-leg temperatures (often 35-45°C in container interiors crossing the Indian Ocean or the Red Sea) would degrade the cargo.
Reefer dimensions and capacity
| Dimension | 20’RF | 40’RH (high cube reefer) |
|---|---|---|
| External length | 6.058 m | 12.192 m |
| External width | 2.438 m | 2.438 m |
| External height | 2.591 m | 2.896 m |
| Internal length | 5.45 m | 11.58 m |
| Internal width | 2.29 m | 2.29 m |
| Internal height | 2.27 m | 2.55 m |
| Internal volume | ~28 m³ | ~67 m³ |
| Maximum payload | ~27,500 kg | ~28,500 kg |
| Set point range | -30°C to +30°C | -30°C to +30°C |
| Power requirement | 3-phase 380/440 V | 3-phase 380/440 V |
Internal volume is smaller than the equivalent dry container because the insulation, the refrigeration unit, and the floor T-bars consume space. A 40’RH gives about 9 m³ less than a 40’HC. Cargo planning has to account for this.
When reefer is the right packaging
Reefer is the right choice for:
- Chemicals with documented temperature stability limits. Class 5.2 organic peroxides above the SADT limit. Some Class 4.1 self-reactive substances. Many pharmaceutical-intermediate APIs.
- Crystalline products that re-dissolve or sinter at high temperatures. Citric acid monohydrate above 30°C will dehydrate; sodium percarbonate degrades. Reefer keeps the cargo within the safe envelope.
- Wax and high-melting-point oils that solidify in cold sea legs. Routes through the North Atlantic in winter can drop a container interior to -10°C; cargoes that solidify or fracture below 0°C need reefer heating.
- Cargoes shipped under controlled temperature regulations. IMDG Class 5.2 substances with assigned control and emergency temperatures must ship reefer with mandatory pre-trip inspection (PTI).
Reefer is the wrong choice for:
- Bulk liquids that can ship in ISO tank. ISO tanks have integrated heating coils that handle most temperature-control needs at lower per-MT cost than reefer-with-drums.
- Cargo where the temperature swing is small. Insulated dry containers (or simply 20-foot dry containers on protected stowage) handle ±5°C variance from ambient; they cost a fraction of reefer rates.
- Routes with poor reefer plug-in availability. Some smaller US Gulf and West Coast terminals can plug only 20-30 percent of inbound reefers within four hours of discharge; the cargo-temperature integrity depends on plug-in continuity.
The plug-in availability problem
A reefer is a refrigerator with wheels. It needs continuous power. The container has a power cable that plugs into a standard reefer socket on the vessel cell, on the terminal yard, on the inland chassis (with genset), or at the buyer’s warehouse. Every transition is a potential power gap.
The choke points:
- Vessel transhipment. The container is unplugged at the transhipment terminal, sits on the yard for 8-72 hours, gets plugged into the next vessel. The cargo temperature drifts during the off-power window.
- Origin terminal pre-loading. The factory loads the cargo, the trucker delivers to the port, the container sits on the export yard. If the export yard has limited reefer plug capacity, the container can be off-power for 12-48 hours before vessel loading.
- Destination terminal post-discharge. Same problem in reverse. A buyer’s truck pickup that runs more than 24 hours after vessel discharge may find a thawed cargo.
- Genset failure on the vessel. A reefer that fails mid-voyage is logged but cannot always be repaired at sea. The cargo arrives warm.
Industry standard is a “no-reefer-plug-in event over 6 hours” SLA, but enforcement is the buyer’s responsibility through carrier-issued temperature monitoring (USB thermologgers placed inside the cargo at the factory) and a contractual right to reject the cargo if the temperature curve breaches the spec.
Reefer rate premium
Reefer rates above dry container rates are substantial:
| Lane | 40’GP rate | 40’RH rate | Premium |
|---|---|---|---|
| Shanghai-Houston | USD 1,500-2,500 | USD 4,500-7,000 | USD 3,000-4,500 |
| Shanghai-Rotterdam | USD 1,200-2,000 | USD 4,000-6,500 | USD 2,800-4,500 |
| Shanghai-Sydney | USD 1,000-1,800 | USD 3,500-5,500 | USD 2,500-3,700 |
Always confirm current rates with the specific carrier. The premium reflects the cabinet manufacturing cost, the plug-in capacity claim on the vessel, and the higher-attention handling.
What genset failure costs
A reefer with cargo at +5°C that loses power for 18 hours during a hot transhipment can rise to +25°C interior. For a cargo with a +10°C maximum spec, that is a rejection event. The buyer’s recovery options:
- Carrier liability under Hague-Visby. The carrier’s liability per package is limited (~SDR 666 per package or SDR 2 per kilogram, whichever is higher). For a 27 MT reefer the kilogram cap dominates: SDR 2 × 27,000 = SDR 54,000, roughly USD 70,000-75,000. Often less than full cargo value.
- Buyer-side cargo insurance. All-risks marine policies generally cover temperature deviation if the policy specifically lists temperature damage as a peril. Check the policy.
- Carrier surcharge for failed-PTI reefers. If the cargo fails the carrier’s pre-trip inspection because the container’s genset shows fault history, the carrier may refuse the booking until repair. This is the better outcome for the buyer.
Always require pre-trip inspection certificate
Before any reefer cargo is loaded, the carrier issues a pre-trip inspection (PTI) certificate showing the container’s refrigeration unit passed a functional test within 30 days. The PTI confirms set-point accuracy, sensor calibration, and genset performance. A PTI dated more than 30 days before loading is a yellow flag, request a fresh inspection or change the container.
Related terms
ISO tank is the bulk-liquid alternative with integrated heating. Twenty-foot container and forty-foot container are the dry equivalents. IMDG Class 5.2 organic peroxides require reefer with controlled temperature. IMDG Class 4.1 self-reactive substances may require reefer.