What Are Cushioning Distances?

As many dangerous goods shippers know, there are many benefits to using 4GV UN packaging. A while back, I wrote a blog that outlined the benefits and regulations of 4GV packaging. Essentially, 4GV packaging allows dangerous goods shippers to utilize one universal package to ship a wide variety of inner containers and articles, provided that the total weight of the inner packaging and packaging materials do not exceed the gross mass listed in the UN marking. To remain in compliance, shippers must closely follow specific packing instructions like any other UN rated Packaging. In the case of 4GV packaging, you may notice the packing instructions mention the term “cushioning distances” included within the assembly directions. When dangerous goods shippers call and are looking for a specific size 4GV box to suit their needs, they often overlook this crucial aspect of 4GV boxes.

What are Cushioning Distances?

Cushioning distance means the thickness of cushioning material between inner packagings and between inner packagings and the outer packaging walls. For example, if you put four glass bottles in a 4GV box, the cushioning distance would be how much cushioning/absorbent is between the glass bottles and between the bottles and the walls within the box. In the case of our PK-3SP 4GV box, you will see the packaging instructions call out a minimum of 1 ½” of cushioning/absorbent on the top and bottom of the inner containers and 1 1/8” minimum cushioning/absorbent between the inner containers and the sides of the box:

If you are putting four glass bottles in this box, there must be a minimum of 1 ½” of cushioning/absorbent on top and bottom of the glass bottles, and at least 1 1/8” between the glass bottles and the walls of the box. In this case, the required cushioning/absorbent is vermiculite (AB-VERM4), as mentioned in the packaging instructions below:

In addition to meeting the minimum cushioning distances, the remaining void (empty) space inside the box must also be completely filled with the required cushioning/absorbent mentioned in the packing instructions. When you choose the correct size 4GV box, the box’s inner dimensions are just one piece of the puzzle; you also have to look at the packing instructions to ensure there is enough room for the required minimum cushioning distances in addition to the size of your inner containers. You can review our packing instructions here.

Are Cushioning Distances Required?

All of the rules of 4GV packaging can be found in the TP14850 at 12.7 and the 49CFR at 178.601 (g) (2), where it states:

“The thickness of cushioning material between inner packagings and between inner packagings and the outside of the packaging may not be reduced below the corresponding thickness in the originally tested packaging; and when a single inner packaging was used in the original test, the thickness of cushioning between inner packagings may not be less than the thickness of cushioning between the outside of the packaging and the inner packaging in the original test.”  

What does this mean? These regulations are essentially saying that the cushioning distances used during the UN testing may not be reduced in any way when using these boxes to ship dangerous goods to remain in compliance. If you need assistance in choosing the correct size 4GV packaging based on your inner containers’ size and weight, feel free to call us at 1-888-442-9628 (USA) or 1-888-977-4834 (CAN). If you are looking to purchase 4GV packaging, vermiculite, or Dust Free 4GV packaging, please click here.

We have all the products, services and training you need to ensure your staff is properly trained and informed.

4GV Dust-Free Securepacc™ Kits

4GV UN Boxes – Variation

Vermiculite, Grade A4, 4 Cu. Ft.

Michael Zendano

Michael Zendano

Michael Zendano started with ICC Compliance Center back in 2016 with several years in the packaging field as a Quality Control Manager. In addition, he has 8 years experience in teaching. Michael works at the Niagara Falls Office as the Regulatory Packaging Expert where he manages packaging projects and procedures and is a member of the Institute of Packaging Professionals (IOPP) and The Chemical Packaging Committee (CPC) . Degrees: M.S. Science of Education.