Why It’s Essential to Use Wheel Chocks and How to Choose Them

It’s a procedure performed countless times each day on loading docks around the world: a trailer backs up to dock and a forklift operator gets to work driving in, backing out, lifting and dropping loads in practiced precision. But on one day back in 2007, OSHA records tell a story of how this routine went horribly wrong when a trailer unexpectedly rolled away from the dock, leaving a gap that the forklift driver backing out of the trailer fell into.

One week later, the driver was still in the hospital recovering from head lacerations and internal injuries sustained in the crash. It could have cost him his life. For his company the financial, emotional and reputational costs could have been ruinous.

And it could all have been prevented by a simple, inexpensive item applied by the driver in seconds: the wheel chock.  

In the fast-moving world of transportation and logistics, it can be a hassle to stop the wheels to do the right thing and the safe thing, like chock your wheels. But it’s critical when you consider the danger posed by heavy trucks, trailers and equipment rolling unexpectedly.

What’s a chock and how do they work? 

Wheel chocks are basically a wedge of heavy material like rubber, plastic or metal that is placed against the wheels of a vehicle to prevent rolling.

They’re especially important in loading docks where they prevent trailers from accidentally separating from the dock or rolling unexpectedly. They also play a safety role in any setting when unexpected wheel movement can spell disaster, including rail yards, airfields and mining operations.

Chocks are one of the simplest, most important pieces of safety equipment at the terminal, worksite or yard because they prevent heavy equipment from creating heavy accidents. They’re so simple that they’re often overlooked and commonly taken for granted.  

Wheel Chocks Can Be Made of Many Materials

Chocks do an important job. They hold back heavy loads. Investing in the right design made of a material that can hold up is a must. Look for models made of the following:

Rubber is the most common material. Whether solid or laminated, rubber chocks are relatively durable and inexpensive. Their downside is that they will corrode and get cut up over time.

Urethane is the durable, lightweight alternative to rubber. They’re more resistant to cuts and corrosion as well as oil or chemicals. More expensive than rubber, urethane is the second most common chock material.

Aluminum chocks are a good choice for heavy-duty uses and high gross vehicle operating weights (GVOW). Many are molded with teeth on the bottom for enhanced grip.

Steel chocks are good for heavy-duty purposes and high GVOW. Sturdier, and as a result, heavier, steel chocks can also be more expensive.

Plastic is a light weight, inexpensive option that can provide additional features to enhance grip or stow away easily in a truck.

What are the important considerations when it comes to chocks?

Wheel sizes, tire conditions, load types, loading docks and even weather conditions vary—and so does the right chock for the job. Consider these variables before grabbing a pair of wheel stops.

Wheel size: The rule of thumb is to use chocks ¼ the height of your tires.

GVOW: Chocks are made to handle different weight ratings. Choose the right model for your load.

Ground surface: For icy conditions, you’ll want a chock with a cleat. Flooded or muddy conditions may call for multiple chocks. A rough lot may call for a resilient metal model.

• Radial tires: More flexible than bias-ply tires, radials will often wrap around the wheel chock, reducing the chock’s effectiveness.
• Tire pressure variation: Harsh environments or improperly inflated tires can make a chock that is a match one day a chocking failure the next.

How many types of wheel chocks are there?

Some may say that any block of wood can be used as a chock, but the tires on a 500,000 lb. dump truck or a 737 will tell you otherwise. Chocks are made for specific industries, weather extremities and load types. That’s why Imperial carries over 100 different wheel chocks and related products in every size, design and material there is. That includes products for airplanes, fire trucks, rail cars, semi-trucks and trailers, mine support equipment, shipping docks, vehicle storage, and heavy-duty shops.

How to Choose the Right Chock for the Application

Chocks by their nature follow a standard pyramid design. That said, there’s no one-size-fits-all chock. They vary in height, width and depth as well as by weight rating and material composition. The other main choices pertain to how much grip is desired because textures, teeth and cleats can add extra bite. Other add-ons include ropes that keep pairs of chocks together or handles that make picking up and positioning chocks easier.

The main challenge of wheel chocks is just ensuring they are available. They have a way of disappearing and it can be hard to find them when you need them—especially when you’re in a hurry making deliveries.

It’s a good idea for drivers to keep a supply of chocks in their truck, lest they are delayed in loading or unloading while they try and locate some at the terminal.  

To keep freight flowing it makes sense for terminal operators to ensure chocks are readily available as well. To prevent them from being “borrowed” or misplaced, chains connecting to the facility are a good call. Opting for a metal model with large handles will also make them harder to steal or destroy.

Know the 9 Basics of Installing Chocks

1. Start by ensuring the parking brake is set
2. Use wheel chocks in pairs—that means right side and left side opposite each other
3. Make sure the chock is centered and squared with the tire
4. Put the chock snug against the tire with a kick
5. Always position chocks downhill and below the vehicle’s center of gravity
6. On trailers, chock the wheels on the axle closest to the loading dock
7. When parking on a downhill grade, put chocks in front of the front wheels
8. When parking on an uphill grade, put chocks behind the rear wheels
9. When the grade is level or unknown, put chocks on the front and back of wheels

The Road to Safety Starts with Following the Law

OSHA has a strong position on chocking. Per 1910.178(k)(1), they say “The brakes of highway trucks shall be set and wheel chocks placed under the rear wheels to prevent the trucks from rolling while they are boarded with powered industrial trucks.”

The law is fuzzy though because OSHA’s jurisdiction overlaps with that of the Federal Motor Carrier Safety Administration (FMCSA). As a result, there is often confusion about whether chocks are required when air brakes or dock locks are being used. The law is also unclear about who is responsible for compliance—truck drivers, dock workers or facility operators.

Practically speaking, carriers, terminal operators and distributors set their own policies with regards to wheel chocks. Considering the danger of trucks and trailers accidentally moving at loading docks, OSHA’s standards should be considered the minimum safety measure.

The road to safety ultimately depends on a team effort where everyone follows policies for chocking and uses established communication procedures. Dock workers and drivers always need to be in sync regarding when chocking is complete and loading or unloading is safe.

It’s Always a Good Time to Talk Chock Safety

Chocks are a perfect example of a small safety measure with enormous consequences. They don’t cost a lot, take a lot of time to install or require sophisticated expertise. The biggest hurdle may just be making them readily available. Create a state with your fleet or loading dock where the right chocks are always right there when they’re needed. Imperial can help. Reach out today.