Forklifts are essential for moving materials in industrial and commercial settings. Safe operation, particularly maintaining the correct fork position while the vehicle is in motion, is paramount for preventing workplace accidents and ensuring the security of the load. Understanding the principles of travel height and load stability is the first step toward professional and secure forklift operation.
The Standard Safe Traveling Height
The industry establishes a standard height for traveling with or without a load to ensure safety and efficiency. Operators should position the forks between four and six inches off the ground during transport. This range provides adequate ground clearance over minor surface irregularities and small debris without compromising stability.
This “driving position” must be maintained throughout the travel path. Keeping the forks low prevents the tips from scraping the floor or snagging on dock plates and expansion joints. The forks should only be raised above this height when approaching a stacking location or adjusting for specific terrain.
Why Proper Fork Height is Essential for Stability
The low travel height directly relates to the combined center of gravity (CG) for the forklift and its load. A forklift’s stability is defined by a theoretical “stability triangle,” and the combined CG must remain inside this triangle for the machine to stay upright. Raising the forks elevates the combined CG, which decreases the stability triangle and increases the susceptibility to tipping.
Driving with the load elevated significantly increases the risk of a lateral or forward tip-over, especially when turning or braking suddenly. Maintaining the load between four and six inches off the floor keeps the combined CG low, maximizing stability and ensuring the operator retains maximum control during transport and maneuvering.
Setting the Correct Fork Tilt Angle
Beyond the vertical measurement, the mast tilt angle is the second control for securing a load during travel. When moving with a load, the mast should always be tilted slightly backward, a process known as raking. This backward tilt cradles the load against the carriage backrest, preventing forward movement.
The tilt secures the load from shifting or sliding off the forks during acceleration, braking, or movement over uneven surfaces. This action also shifts the combined center of gravity slightly closer to the forklift’s front axle, enhancing stability. Unstable or liquid loads may require a marginally greater degree of backward tilt for added security.
Adjusting Fork Position for Specific Terrain and Conditions
While the four to six-inch rule is the baseline, real-world conditions may require temporary modifications to the fork height. When traveling over rough, uneven, or outdoor surfaces, the forks may need to be raised slightly to prevent the tips from snagging on larger obstacles. Any increase in height must be minimal and temporary, returning to the standard position as soon as the terrain allows.
Driving on inclines, such as ramps or grades, requires a specific approach to maintain stability. When traveling up or down a ramp with a load, the load must always face uphill, regardless of the direction of travel. A loaded forklift drives forward up a ramp and in reverse down a ramp. An unloaded forklift always travels with the forks pointed downhill. Operators must also check the overhead clearance of the load and the overhead guard when approaching doorways or low-hanging structures.
General Safety Rules for Traveling with a Forklift
Proper fork positioning is one component of safe forklift travel. Maintaining a safe speed, generally no faster than five miles per hour, is necessary for controlled stopping and maneuvering. The weight of a loaded forklift means it can take 15 to 20 feet to come to a complete stop from full speed.
Operators must always look in the direction of travel and maintain a clear view of the path ahead. If a load obstructs forward visibility, the operator must proceed in reverse, looking over the shoulder. Sounding the horn at intersections, blind corners, and doorways alerts pedestrians and other vehicle operators. Maintaining a following distance of at least three forklift lengths behind other equipment ensures sufficient stopping distance.