Saturday, May 25, 2024
shipping and freight resource services
HomeFreight ContainerSpecial Containers & its Cargoes - OOG/Reefer - A Refresher

Special Containers & its Cargoes – OOG/Reefer – A Refresher

The ubiquitous shipping container recently celebrated its 68th birthday and has become the lifeblood of global trade..

Around 866 million TEUs were shipped globally in 2023 with the volume projected to reach 988 million TEUs by 2027..

As we know, there are several different types of containers in the container fleet of the various shipping lines..

  1. Dry Van or General-Purpose Containers (Standard & High-Cube)
  2. Open Top Containers (Soft Top & Hard Top)
  3. Flat Rack Containers (Fixed End, Collapsible/Platform, Super-Rack)
  4. Tank Containers
  5. Refrigerated (Reefer) Containers
  6. Side Door Containers
  7. Bulktainers
  8. Various other custom containers

The wide spectrum of cargoes shipped in containers across the world on almost every container ship includes a diverse array of special cargoes such as Out of Gauge (OOG) and Refrigerated (Reefer) cargoes..

They are termed as special cargoes and special containers because these require particular attention due to their unique cargo handling, storage needs, permits, approvals, equipment, regulations, and documentation..

Out of gauge Cargo (OOG)

OOG cargo is cargo that cannot fit into a normal GP container as it exceeds the dimensions of the GP container in terms of length, width, and/or height.. (View the “generic” container dimensions)

OOG cargo is carried in Open Top containers (OT) or Flat Racks (FR), due to the nature and size of the cargo..

Open Top Containers – This type of container is used for loading cargoes that are over-high like machinery, vehicles, tyres (see below), steel coils etc..

Special Containers & its Cargoes – OOG/Reefer
Image: Hapag Lloyd

It is also used for in-gauge cargoes that cannot be easily loaded through the door and need to be loaded from the top (like glass)..

Special Containers & its Cargoes – Open Tops - OOG/Reefer
Image: Hapag Lloyd

Flat Rack Containers – Mainly used for cargo that exceeds the width (referred to as over-width) or height (over-high).. If the cargo is just over-width or over-height, fixed-end flat racks can be used where the ends of the container are fixed and cannot be folded..

There are also collapsible flat racks or platform containers where the ends of the container can be collapsed to form a platform and cargo is loaded on top of it..

Special Containers & its Cargoes – Flat Racks - OOG/Reefer
Image: Hapag Lloyd

Both fixed-end and collapsible flat racks are used in combination to load cargo that is over-width, over-length, and/or over-high.. Big machinery, heavy equipment, project cargo, large vehicles on tracks, boats, big reels, etc are loaded on this type of container..

Platforms are also used underdeck of the container ship to load oversized cargo across several containers, like below..

Special Containers & its Cargoes – OOG/Reefer
Image: CMA CGM

Super-racks are another type of flat rack with a difference in that in a Super Rack container, the corner posts can be extended upwards to increase the height to cater to high cargo as shown below..

Special Containers & its Cargoes – OOG/Reefer
Image: CMA CGM

Reefer (Refrigerated) Cargo

Although these cargoes and containers have become a regular feature on many container ships, reefer containers are considered special due to the many requirements for the perishable cargo carried on these containers..

A refrigerated container or reefer container is a shipping container used for the transportation of temperature-sensitive cargo..

A reefer container has its own integral and inbuilt refrigeration unit but its also relies on external power, from electrical power points at a land-based site, a container ship, or on a quay..

Special Containers & its Cargoes – Reefer Containers - OOG/Reefer
Image: Hapag Lloyd

When transported over the road on a trailer these reefer containers are powered by generators (“gensets”) clipped onto the reefer container on road journeys..

Reefer containers are used to carry many cargoes that are sensitive to temperature changes and require a temperature-controlled environment.. Examples include Frozen Meat, Fresh Produce, Fruits, Vegetables, certain Chemicals, Photo films etc..

perishable cargo in reefer containers - shipping and freight resource

Reefer containers have also evolved to be smart, capable of providing real-time tracking and information relating to humidity, and temperature settings, and is also used in Cold Treatment Sterilisation for shipment of fresh produce..


The shipping industry’s ability to adapt to the requirements of special cargoes through technological innovations in container design is a testament to its crucial role in global trade..

Each type of special cargo and container solution exemplifies the intricate and fascinating world of global trade, shipping, freight, and logistics, highlighting the industry’s adaptability and technological advancements in facing modern shipping challenges..

Understanding the specific needs and appropriate shipping methods for OOG and Reefer cargoes not only enhances logistical efficiency but also minimizes the risk of damage, ensuring that goods arrive at their destinations safely and in optimal condition..

As global trade continues to evolve, so will the technologies and methodologies employed to transport these critical cargoes across the world’s oceans.. The industry is continually innovating to meet the demands of transporting these complex cargoes as these cargoes form essential components for many industries..

Article republished after critical updates

Liked the content..??

Sign up below to receive the best and most reliable industry content for free from THE Definitive Online Resource for Shipping and Freight..




Hariesh Manaadiar
Hariesh Manaadiar
I am Hariesh Manaadiar, the Founder of Shipping and Freight Resource.. I have been in the dynamic shipping and freight industry for over three decades and have worked in several sectors.. I share my experiences and knowledge of the industry through this blog for those looking for help in the industry.. Stay subscribed for more free useful content about shipping, freight, maritime, logistics, supply chain and trade..


  1. Great Article I would like to introduce GenFlat Marine Collapsible containers
    Our containers have received awards for the best innovation in the container industry

  2. Thanks much to know shipping knowledge more about containers & others related .
    I am working for handling shipping document .

  3. I am a subscriber of your valuable blog since a couple of months ago. As a commodities trade finance consultant, I understand that some cargoes in commodities trade, such as agricultural produces etc. may need good ventilation to avoid damages during the hot and humid sea voyage. A special container providing ventilation is named “Fantainer” (with fans to provide ventilation). Please elaborate more on how the various “load plan” softwares introduced in your blog deal with proper stowage of fantainers that need to face the open fresh air in order to make ventilation possible. Certainly fantainers should not be stowed “under deck” (limited or no ventilation) or “on deck” but surrounded, blocked or “suffocated” by other near by containers.

  4. Hi, I am new to sea freight but am learning fast.
    I always have problems on loading. that is given a packing list & to determine how many & type o containers to be used based on the packing list given.

    Latest, i have been given to determine what type of equipment to use if packing list of
    2 units of aircraft engines 197 x 100 x 115 inches weight 7000kgs/each unit & 2 units aircraft engines 232 x 100 x 120 inches weight 7000kgs/each .. which & how many flat rack to use.
    Shipment destined to UK.

    Thank you for your asisstance. I have been looking for sites that can assist on loading of container whether OOG or normal GP..

    • Hi Leazz, thats a difficult question to answer coz it depends totally on the vessel involved and the planning of the vessel.. The only time you will ever know FOR SURE is when the planning for the vessel is done..

  5. Hi, my management gave me a project on OOG and flat racks. I need to study them and give details such as loading/discharging procedures, from one end to another, stuffing and unstuffing and so on. Could you kindly assist me please? Thanks. Léazz

  6. The pictures for 20’/40′ PL (platform/tweendeck/bolsters) are in fact pics of collapsible Flatracks. Platforms do not have any
    end piece (collapsible or not). PL’s mainly used on RORO vessels to cater for non-wheeled cgo. True, you can in some instances use collapsed FR’s for the same purpose but generally load capacity is considerably different.

    For reefer containers suggest you go into more details of the different types of reefer containers on the market today. A long way fm the original SAECS clip-ons/simple reefer boxes. One example CA (controlled atmosphere) reefers. Interested readers can check websites for more info or contact PPECB.


Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.



Sign up below to receive the best and most reliable industry content for free from THE Definitive Online Resource for Shipping and Freight..



FBX - Freight Indices