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Cargo Control and Physics: Beware of the Force

The Federal Motor Carrier Safety Administration (FMCSA) revised its long-standing cargo control regulations for commercial motor vehicles back in 2004. Since then, the rules have remained largely unchanged. They account for all types of trucks including flatbeds, refers, tankers, and even dry goods vans.

In short, truck drivers are required to properly secure their cargo prior to transport. Nothing can be allowed to move, let alone become dislodged and fall off a trailer. Dry van and reefer operators have less of a challenge given that their cargo is enclosed on all sides. Flatbed operators do not have that luxury. They have to secure their cargo by tying it down to the trailer bed.

In light of that, truckers with the best cargo control skills are the ones that understand physics. They understand the four forces that cargo is subject to during transport. They account for each of those forces by blocking and tying down cargo in specific ways.

The four forces are:

Forward force – experienced during braking
Rearward force – experienced during acceleration
Sideways force – experienced when making turns
Upward force – experienced when hitting bumps or on rough road.

The biggest of these four forces is forward force. This goes without saying. It is the greatest force because it is exerted as a result of cargo continuing to want to move forward even as the vehicle is decelerating. Forward force is a combination of kinetic energy, the weight of the cargo, and the vehicle’s rate of deceleration.

Tools for Overcoming Force

The revamping of FMCSA rules included some new rules for tie-downs, blocks, and other cargo control equipment. Though we will not go through the details here, it is sufficient to say that the government made it clear that they expect truck drivers to use the right kinds of tools to keep cargo in place. The rules specifically mention:

Bulkheads – Bulkheads are sometimes referred to as headboards or front-end structures. They are generally attached to the front of a flatbed trailer and used to block cargo from moving forward. Bulkheads are not required by law.

Webbing Straps – Webbing straps are used to tie down cargo when heavier chains are not required. They are made with synthetic materials that offer maximum control with a low weight cost.

Other Equipment – The rules go on to address chains, wire rope, steel straps, blocks, shackles, winches, and more. Fortunately for truck drivers, the rules do not stipulate how each of these different things have to be used to secure cargo. The rules only talk about the cumulative effect of choosing the right equipment.

It is interesting to note that the rules also draw a distinction between securing devices and tie-downs. Obviously, a chain qualifies as both. But while all tie-downs are also securing devices, not all securing devices qualify as tie-downs. Therefore, truckers have to make the distinction in their own minds as well.

There are very specific rules relating to the number of tie-downs necessary based on the length and weight of a load. The number of tie-downs is independent of other cargo control equipment, save the bulkhead. Why? Drivers can use fewer tie-downs if a bulkhead prevents cargo from moving forward. On the other hand, blocks do not reduce the number of required tie-downs.

It is All about Physics

We have said multiple times in the past that cargo control is all about physics. If you understand the physics involved, you should understand the four forces that are working hard to dislodge cargo. Keep those forces in check and your cargo will stay in place.