Ergonomic cases study for workers who install windshield molding. This is a fictitious job but reflective of common work situations on an auto assembly line.
Worker position: Two workers are on each side of the car assembly line wearing heavy gloves.
Get equipment: Each worker gets two screws and a powered screw driver from the stock area at the side of the line.
Secure grill: The two screws are driven into the top horizontal edge of the firewall to secure the grill in front of the windshield.
Get windshield molding: While one worker is putting a clip on the battery mount, the other operator gets a rubber windshield molding and places it on a rack.
The airline tends to twist the tool from hand when driving screws, causing impulse force to the hand/wrist..
Extreme wrist flexion is necessary to use the pistol shaped tool.
Use an in-line tool suspended from an overhead trolley. This will reduce wrist flexion. The suspension should have articulating linkage that will resist torque and impulse forces at the wrist.
Armstrong, Thomas J.; Fine, Lawrence J.; Joseph, Bradley; and Silverstein, Barbara. Analysis of Selected Jobs for Control of Cumulative Trauma Disorders in Automobile Plants. Ann Arbor, Michigan: The University of Michigan, 1984.