In a perfect world, nothing would have to be lifted at the workplace, no strain from lifting would ever be placed on a worker’s back and back-related worker’s comp claims just wouldn’t have to exist.
This is anything but a perfect world.
According to a report by the American Academy of Orthopaedic Surgeons, back pain is second only to the common cold for keeping American workers from their jobs. It’s estimated that two percent of the workforce will receive some sort of compensation for a back injury this year and claims payments for back injuries will be in the billions.
While back pain may be a fact of life for 80 percent of the population, that doesn’t mean that lifting tasks in the workplace need to aggravate the condition, so attempts to mitigate the potential for injury are made through changes in the workplace. One of these changes is to train employees in “proper lifting.” But does using what has been deemed a “proper lifting” technique really make a positive impact?
Any time an ergonomic change is made in the workplace, the goal is to increase the overlap between worker capabilities and task demands to create a better fit between worker and task. Changes are traditionally handled through a hierarchy of controls: engineering, administrative and behavioral. When lifting is the task, ideally an engineering control, one that changes the physical features of the workplace, would be put to use. For example, equipment that lifts the object for the worker could be brought into the workplace, objects like boxes or bolts of fabric could be made smaller or a conveyor belt or cart could be used to transfer the object from place to place.
If engineering controls don’t fix the task, the next step should be to address administrative controls, ones that reduce the worker’s exposure to the hazard. Can a task that presently requires a box to be lifted from a pallet, carried 20 feet, stacked on a set of shelves as temporary storage, moved to a workstation, have its contents checked and inventoried and then placed back on a pallet be altered so that the box is inventoried instead while it’s on its original pallet therefore eliminating the extra steps of lifting and moving the box?
“Proper lifting,” however, doesn’t address the first two types of controls in the hierarchy; instead it places the responsibility of change on the employee by becoming another part of the worker’s job to make sure he or she is following the steps to properly lift the object. But when a worker becomes injured because of on-the-job lifting tasks, regardless of whether he or she was performing the lift in the manner recommended by the employer, the injury becomes the employer’s responsibility and the aftermath is ultimately the employer’s burden.
The theory behind “proper lifting” is that the lift-with-the-knees posture minimizes compression forces in the back. Training workers in how to lift attempts to improve the biomechanics of the way people lift. But what it doesn’t do is look at the whole picture. Rather lifting techniques go after the symptom, not the cause.
Among other suggestions, workers being taught “proper lifting” are usually instructed to keep their backs straight, bring the object close to their body, lift with their legs, avoid twisting and reverse the process when putting the object back down. And while a stance like this can help lessen the impact of lifting, from a practical perspective, it can also put a stress on other parts of the body (for example the knees) and it has the potential to slow the worker down which can directly conflict with management’s desires and natural human behavior.
NIOSH has attempted to address lifting through the NIOSH Lifting Equation, a formula to help determine a Recommended Weight Limit (RWL) and the Lifting Index (LI). The RWL is the recommended weight of the load that nearly all healthy workers could lift over a period of time (up to eight hours) without an increased risk of developing lifting related low back pain or injury, given all other task parameters remain unchanged. The LI is a relative estimate of the physical stress associated with a manual lifting job. As the magnitude of the LI increases, the level of the risk for a given worker increases, and a greater percentage of the workforce is likely to be at risk for developing lifting-related low back pain.
Ideally, rather than teach proper lifting or develop standards and equations that state when a lift is okay, workplaces would address engineering controls that encourage good posture and help eliminate risky lifts. And there’s a bonus to this philosophy
This article originally appeared in The Ergonomics Report™ on 2003-09-01.