The books are manually lifted to a desk where their bar code is read using a light pen. Some manual computer entries must be made using a keyboard also located on the desk top. After the bar code is read the books are placed under a re-sensitizing machine and then placed on another cart from which they will be placed on the library shelves.
Employees can sit or stand during the process.
There are frequent and forceful, elongated pinch grips, torso flexions, and the job entails long periods of time with the head bent forward. It is difficult to determine the absolute number of repetitions, or period of time that a posture can be maintained or an activity performed, which will cause an injury. But the risk of injury is definitely increased as static posture times or repetitions of a movement are increased. There appears to be sufficient frequencies of stressors associated with this task to cause musculoskeletal injuries unless adequate engineering and administrative controls are implemented. Many of the engineering controls will be addressed in the following sections.