Shipping container markings: What do they mean?

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If you are looking at shipping containers, you might notice a lot of container markings that play an important role in the supply chain.

In order for you to choose the right shipping container, you need to understand this container identification system that you understand exactly what the container can (and cannot) handle.

For example, you do not want to exceed the maximum weight of the shipping container. With this in mind, what are a few examples of shipping container markings? What do they mean for the container?

Learn about some of the most important symbols and markings below.

Many Shipping Container Markings Are Compulsory

There are container markings that are required on just about all types of shipping containers. In many situations, these markings have to be placed on the door where they are conspicuous.

Each of the markings placed on the door plays a major role in the transportation process. They are all important when it comes to the safety and monitoring of shipping containers.


A few of the most important markings that you might come across include:

The Container Number

One of the first markings that you might notice is the container number. This is the most important marking on the door. They can also be a bit complicated.

It is usually an alpha numeric sequence and contains four letters and seven numbers. This is a code that is used to identify containers internationally as they travel from place to place.

Usually, these markings are assigned by the International Standards Organization (ISO) classification agency.

It is important for you to make sure you are familiar with the number of each container and what this means. A few important parts of this sequence include:

The owner prefix refers to the first three capital letters in the sequence. It is a unique identification code that is usually registered with the Bureau International des Containers et du Transport Intermodal (BIC). It should be possible to do a BIC code search to identify the owner of the container.

The equipment category identifier is the fourth letter in this alphanumeric sequence. This equipment category identifier is often grouped together with the owner code, forming the alpha prefix.

The serial number or the registration number refers to the first six digits and is usually decided by the owner of the container.

The final number is called the check digit. It is usually displayed off to the side. Even though it might not seem important, it is important for determining whether the ID is valid. There is a check digit calculator that can validate the container.

This series of letters and numbers is the most important marking on the container. It is important to familiarize yourself with the type code and ISO identification markings of the container.

The ISO Code

Every container is also given something called an ISO code. This is distributed by the BIC to avoid issues when it comes to naming the container.

Different companies measure the dimensions and weight of the container in different ways depending on its location.

Therefore, it is important to use this ISO code to avoid confusion when it comes to the maximum weight, tare weight, and other dimensions of the container.

In the ISO code, the first character refers to the length of the container. The second character refers to the width and height of the container.

Finally, the third character refers to the type code and other characteristics of the container. Sometimes, this code can also be used to indicate a container of reduced strength.

This is important to know if you are going to be put in your cargo in the container itself.

The Weight Limit

In addition, there are also going to be markings on the container that refer to various weight limits. For example, there will be a maximum weight listed on the container.

This is usually something that is measured in kilograms. The weight limit displayed on the container also includes the weight of the container itself.

This should make it easier to weigh the container when determining if it is going to be over capacity.

There will also be a marking for the tare weight of the container. This is the actual weight of the empty container.

Remember that the tare weight is probably going to be included in the overall weight limit of the container itself. The tare weight of the container needs to be considered before the containers are loaded onto a ship, empty or full.

That way, ship operators can avoid planning problems and a potential disaster at sea.

If you take the difference between the maximum weight and the tare weight, you will have the maximum payload.

This is the maximum amount of weight that can be packed in the container itself. This is the weight that is also shown on the bill of lading.

It will not include the tare weight. It is important to know the maximum pack weights so that you do not overfill the container.

By the way, the container should also have a maximum volume that can be packed as well. This is usually listed beneath all of the other weight limits.

The volume refers to the cube capacity. Containers are very sturdy, so you should not be able to overpack the volume of the container; however, it is still important for you to keep this in mind when you are deciding what to put inside the container.

The Periodic Examination Scheme (PES)

Before a container can be loaded onto the ship, it has to have a valid ACEP sticker or Next Examination date under the PES scheme.

The containers have to be inspected from time to time to make sure they can stand up to routine wear and tear.

After a container is manufactured, the first inspection is usually not due for five years; however, even if the container is safe, at least have a valid sticker before it can be loaded.

The CSC Plate

Finally, the container also needs to have a valid CSC plate which ensures the container is in good condition. This is important for safety purposes.

It contains all of the manufacturing data and information regarding the equipment owner.

It is important for you to be familiar with the information included on the CSC plate so that you know how to take a look at the area safety parameters of the container.

There are a lot of markings that you need to understand if you are going to be working with a shipping container.

There may be additional mandatory operational markings, such as overhead electrical danger safety alerts, that you need to be familiar with as well.

Choose the Right Shipping Container

These are just a few of the most important markings that you may notice on your shipping container.

It is important for you to learn about this shipping container system so that you choose the right container for your supply chain purposes.

Remember that there are other black markings that could be industry-specific. Therefore, if you are looking at a shipping container and do not understand one of the markings, remember to ask for assistance. 

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About Emma

Hey there! I'm Emma. When I'm not wrangling kids I like to walk aimlessly around hardware stores and watch HGTV for hours on end.

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