Dunnage Bags vs. Polystyrene / Styrofoam

Dunnage bags act very differently from polystyrene, aka styrofoam blocks,  when it comes to the actual stowing and securing of cargo inside shipping containers. Whereas dunnage bags are a CTU Code Compliant cargo securing device, polystyrene is regarded as just a void filler, not an actual cargo securing device.

This video demonstrates the performance of both producs and it will be clear to you that dunnage bags secure and stow cargo, and polystyrene does not.

The video was shot at Cordstrap’s Global HQ Test & Training Center in The Netherlands.

Polystyrene or Styrofoam inside shipping container 

First, 4 box pallets are loaded and polystyrene, or styrofoam, is placed between them to fill the void. After this process, we start tilting the container. As soon as a tilt of only 25 degrees is reached, the load starts to move and fall out of the container.

Dunnage Bags inside shipping container 

During the next test, we use the same 4 box pallets, but this time place a dunnage bag between them. As with the polystyrene, we start tilting the container.

The test with the dunnage air bags went well and demonstrates that the dunnage air bags secure the cargo against movement in 5 different directions. The force applied to the cargo by the dunnage bags is enough to prevent the cargo from moving forward, backward, left, right or up. The downward movement will be prevented by the loading floor.

Conclusion – polysterene or styrofoam DOES NOT secure your cargo and prevent cargo damage

Before the test we already knew that polystyrene or styrofoam blocks are not capable for proper load securement. A small space will always remain between the load and the blocks or between the wall and the blocks. You can use the blocks to decrease the voidspace in order to absorb part of the load movement. However, they are not a solution to prevent transportation damage. In most cases, dunnage air bags will have a much greater effect in keeping a load in its place.

Aside from the cargo securing properties of dunnage bags, dunnage bags have many other benefits over styrofoam blocks. Unlike polystyrene/styrofoam, Cordstrap dunnage bags are fully recyclable and therefore are an environmentally friendly option. Removing and disposing of dunnage bags is much easier for your customers as well.

If you like more information about Dunnage Bags, please visit the Dunnage Bag Section on our website.