She tended to lean over even while checking. Poor posture is known to cause a variety of musculoskeletal injuries especially in the shoulder and neck. Some devices will read the information from magnetic strips on customer ID cards. Work activities at rates higher than this are known to be associated with the development of carpal tunnel syndrome. Allow and encourage the employees to take frequent breaks and encourage them to be occupied in non-hand intensive activities during those breaks.
Breaks are for rest from the highly repetitive scanning operation.
Without automation, high repetition rates are difficult to avoid in this operation. Rapid accelerations are the most injurious actions during the cycle. Employees must be trained to make smooth movements, keep the wrists neutral and share the burden between the left and right hands. Multiple identical items should be keyed in as a group. Administrative controls over pricing of like items and training of employees of such a system will mitigate this.