Pushing and pulling tasks are daily life occurrences, particularly, in the workplace. Because of the extreme stress these two forces exert on the body and the frequency with which push-pull tasks must be performed, pushing and pulling result in an extraordinarily high number of musculoskeletal injuries each year. These injuries, which cost U.S. businesses tens of billions of dollars annually, are largely preventable when ergonomic practices and ergonomically-designed equipment are introduced into the workplace.
Surprisingly, it’s not the weight of the load that makes push-pull tasks so physically demanding, it’s the horizontal push force needed to initiate and sustain movement that places the greatest strain on the human body. In order to overcome natural inertia, tremendous force must be applied to initiate motion of a cart or piece of heavy equipment. As the operator strains against inertia, he must exert extraordinary force to start the cart or piece of equipment moving. In his exertions, the operator places unusual strain on the muscles and tendons of his legs, back, shoulders, arms and wrists. Pressure decreases as the load begins rolling as less force is needed to keep a moving load in motion. However, every time the operator must stop and restart motion, for example to onload or offload parts at a workstation or turn a corner or maneuver through a tight space, he must again exert the extraordinary force necessary to overcome inertia, risking serious musculoskeletal injury each time.
Of the two methods used to move carts and pieces of heavy equipment, pushing is always preferable to pulling. Pulling places greater strain on the body than pushing. It forces the worker to assume positions that minimize the application of force and increase the risk of injury. There are two ways to pull a load: using one hand and facing the direction of travel or using two hands but walking backward and facing away from the direction of travel. Both are problematic and increase the risk of operator injury. Next time we’ll talk about the specific risks involved in each type of pulling task.
The severe strain placed on the body when pulling and maneuvering heavy loads or heavy equipment is eliminated with the use of DJ Products’ ergonomically-designed, motorized carts, tugs and movers. DJ Products’ motorized carts and movers allow operators to safely and without effort move and maneuver carts and equipment with just one hand. DJ Products’ walk-behind design guarantees maximum operator control and safety with full view of the path ahead. Visit the DJ Products’ website for more information about our full line of ergonomically-designed carts, tug and movers.
Next time: Risk factors in pulling tasks