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Everything you need to know about Container Seals

Everything you need to know about Container Seals

Everything you need to know about Container Seals

How a typical container seal looks like

What are Container Seals used for?

Once sealed, the seal cannot be opened without cutting it. Since it can only be removed once, this ensures that the container remains unopened until it has been delivered to the recipient.

As such, the main function of the seal is to deter the theft of goods, as any broken seal typically indicates that it has been tampered with.

It also minimizes the risk of an unauthorized person accessing the container to transport illegal cargo (such as contraband or drugs).

Common Types of Container Seals

Container seals can come in many shapes, sizes and materials.

Depending on the shipping line, exporter or the level of security required, containers can be secured with any kind of seal.

The two most commonly used types are:

  1. Bullet or Bolt container seal
  2. Cable container seal
Bolt Seals
Bullet or Bolt seals
Cable Seals
Cable seals

Regardless of the type of seal, the most preferred type of seal complies with the requirements of the ISO PAS 17712 chapter.

Do the different colours of seals mean anything?

Container seals come in a variety of colours. Typically, each shipping line has their own seal colour.

The colour of the seal is not representative of the type of cargo that the container holds.

Where on the container should I place my seal?

Every shipping container has two doors that open outwards, with two lock rods on each door.

Typically, there are six locations on the container doors where you can lock the seal.

Container Door Seal Locations
Locations to place the container seal.

The left door closes first, followed by the right door. It is thus common practice to place the container seal on the right door of the container, as it will be opened first.

As can be seen the image above, the seals should thus be placed on any of the 3 lock rods on the right door (circled in red).

How do I put on the container seal?

For bolt seals, when it arrives, it should contain 2 parts: the top and bottom. 

There should be a unique seal number on both pieces.

Seal numbers on a bolt container seal
Bolt seal with a seal number on both parts.

To use the seal, you should snap the 2 pieces apart.

A bolt seal is made up of 2 parts
A bolt seal is made up of 2 parts.

When you are done with stuffing your container, close the doors, insert the pin through the hole, and connect the base to the pin to secure the bolt seal.

How to lock a Bolt Seal
Locking a Bolt Seal

What are the numbers we see on a container seal?

Each seal should be identifiable by a series of numbers and/or letters.

In a typical export process, the prime mover driver will collect an empty container from the depot, together with a seal.

The haulier/shipper will need this seal number for documents related to the container, such as permit declaration, the electronic shipping note (ESN) and on the Bill of Lading (BL or BoL).

In Singapore, in order to enter the port with a container for export, hauliers will also need to provide Portnet with a seal number. This is to declare the cargo and the weight of the goods to be exported to the port authority.

Eventually, before opening the container, the recipient should check the seal number to see if the seal received is the same as the one listed in the Bill of Lading.

What should I do if my container seals are mismatched?

If there is a discrepancy between the seal and Bill of Lading, you should contact the shipping line immediately and try to get the issue resolved.

If possible, avoid opening or unloading the container until a representative of the shipping line is present. This is crucial in the event of a claim.

What should I do if my container seals are broken?

If the container seals are broken, it can mean that someone has been tampering with the goods or there has been a theft.

However, it can also mean that there the container has been selected for Customs inspection (refer to next point). In such cases, the new seals will be clearly marked so that you will know that it has been broken by Customs.

What happens when my container has been selected for Customs inspection?

In Singapore, the Singapore Customs conduct selective supervision of unstuffing of import containers and transhipment containers to ensure compliance with regulatory requirements.

This is usually done to check that all goods conveyed in the containers have been accurately declared to Customs.

Containers that have been identified for unstuffing under Customs supervision will be directed to the Red Lane by the Port Messaging System. There, your container will be checked by Customs officer(s). 

Before the check, the original container seal will be removed. Afterwards, the container will be sealed again, this time with a Customs seal.

In Singapore, the container can be resealed with either a Customs red or green seal. For red seals, they may also be affixed with a warning sticker.

Singapore Customs Green Seal
Singapore Customs Green Seal
Singapore Customs Red Seal

What do I do if my container is affixed with a Customs red seal?

If your container has been resealed with a red seal, you will need to apply for Customs supervision for unstuffing.

You should not break the Customs red seal and/or unstuff the container without prior approval from Singapore Customs.

The prime mover driver will be issued a “Notice to Haulier”, who will need to inform the shipper or forwarder of the Customs supervision requirement.

You will then need to apply for Customs supervision of unstuffing within one working day of clearance of the container from the checkpoint, to be submitted via e-filing at www.customs.gov.sg. The intended date of unstuffing should be at least one working day from the date of e-filing.  The actual time slot allocated for the customs supervision will be subject to Singapore Customs’ manpower availability.

Singapore Customs Red Seal with Warning Sticker
Singapore Customs Red Seal with Warning Sticker

Do I need to do anything if my container is affixed with a Customs green seal?

If your container has been resealed with a green seal, there is no need to apply for Customs supervision.

The prime mover driver will not receive any notice, and no approval is required from Singapore Customs to break the Customs green seal.

How do I remove container seals?

Seals should not be removed by prime mover/truck drivers. They should only be removed by the recipient at the destination’s end.

As seals are made to be tough to break, the best way to remove them is with a bolt cutter.

Bolt Cutter
Bolt Cutter
Where do I cut the seal?

Using a bolt cutter, cut along the length of the seal.

You might need several tries before the seal can be cut clean through.

Cutting a Bolt Seal
Cutting a Bolt Seal

Do container seals guarantee that my cargo is secure?

Although container seals cannot be tampered with easily, they are not entry-proof. They are meant to deter unauthorized activity, and to provide evidence of tampering.

However, as an added security measure, you can opt to use multiple seals to secure your container.


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