Chocking and Blocking Safety

What’s at Stake?

Chocking is the act of using a wedge to immobilize the wheels of a vehicle or equipment to keep it from accidentally moving. Chocking the wheels of a vehicle, such as a truck or trailer, physically stops the movement of wheels to prevent runaways that can injure workers and destroy property.

Blocking is the act of using lumber to keep cargo in place. Blocking stabilizes cargo to prevent shifting and trailer overturns. Blocking also creates a physical barrier on equipment to prevent unintentional activation during maintenance.

What’s the Danger?

A worker was repairing a front-end loader with the bucket raised but without following LOTO procedures and without putting blocking on the hydraulic arms of the bucket. The hydraulics start to lose pressure and the bucket falls to the ground and fatally crushes the worker.

A by-stander is struck and receives disabling injuries after a delivery driver failed to properly chock the wheels on her truck.

These are just two examples of how dangerous it can be when you don’t practice chocking and blocking.

How to Protect Yourself

Chocking

• If you drive a truck, tractor, or other mobile equipment, use special caution when exiting the vehicle.
  • Ensure the brakes are set, the vehicle is at a complete standstill, and that it will not roll forward or backward before you exit.
• To chock a freestanding vehicle place chocks on the left and right rear axle wheels.
  • It is safest to chock both the front and back wheels on both sides of a vehicle.
  • Some vehicle wheels may also need to be chocked at the front and back of each tire.
• To secure vehicles at loading dock, first make sure the trailer is backed up against the loading dock edges and place chocks on the left and right wheels that are closest to the loading dock.
  • This placement allows a forklift to push down on the trailer wheels and seat them more firmly against the chock.
  • When only the front axle is chocked, the forward motion of a forklift entering the trailer can loosen the chock, allowing the vehicle to creep forward or jump the chock.
  • The safest bet is to chock both the front and back wheels on both sides of a vehicle.
• Only use chocks designed to be used with trucks, vehicles and equipment. Stay away from lumber, cement blocks, rocks, or other homemade items.
  • Store chocks inside trailers so they are easy to find and readily available.
  • Chain chocks to loading docks to keep them from being misplaced.

Blocking

• Block cargo to prevent loads from shifting during transport and unloading. If you don’t, a sudden shift in the center of gravity can overturn a trailer and unstable loads can strike, crush, or engulf workers when the materials are unloaded.
• Get in the practice of blocking all cargo – not just wheeled or round items.
• Items should be blocked separately and on all four sides with lumber and nails or spikes thick enough and long enough to keep the cargo in place.
  • Drive nails or spikes into the lumber at opposing angles.
• Never use other cargo for blocking— it doesn’t prevent movement in the same way a block can and may cause your cargo to overturn.
• Keep your hands, fingers, and the rest of your body out of dangerous pinch points.

Final Word

Chocking and blocking are good practices to prevent heavy loads and vehicles from unintentionally moving. If you are loading or unloading, hitching or unhitching, or performing maintenance on a vehicle, you must take time to chock and block the equipment to protect you and others from unintended movement of the equipment and/or cargo.