Repeated bending of the torso, even if there is no load in the hands, is a recognized risk factor for back injuries since the weight of the upper body must be supported. Fatigued muscles are more prone to injury and provide less support during a task. Lifting a load while bending forward or lifting larger parcels using deep squat postures tends to move the load away from the body.
Compressive forces placed on the spine increase the farther the load is moved away from the body.
This is especially important for package car unloaders and truck loaders who lift parcels from floor level, where the risk of injury is greatest. Knowledge of a parcels weight will allow employees to seek assistance, if necessary, prior to attempting the lift. The recommended weight, for tagging, will vary depending on the lifting conditions, but generally items weighing more than about 30 to 40 pounds are tagged. The company already knows the weight of the packages and the technique of tagging heavy packages is standard practice at many of the airlines. Hinge the floor mounted conveyor such that sections can be tipped back out of the way to give employees a larger area in which to work.