Screen-print Industry – Ergonomic Squeegee Handles
Workers in the screen-printing industry use wooden-handled squeegees to force ink through a screen and into a substrate. The industry standard handle is approximately 1 inch wide and is grasped in both hands using a pinch grip. The narrowness of the grip requires forceful contractions by muscles in the forearm and wrist. When the user exerts significant downward forces with the handle, the handle places pressure on the mid-palm of the hands, causing possible compression of the median nerve.
Repetitive use of hand tools (particularly those that compress the palm of the hand and are held with a pinch or precision grip) may result in the development of carpal tunnel syndrome and other musculoskeletal disorders of the hand, wrist, and arm.
Squeegee handles for manual screen print workers can be ergonomically designed to conform to the shape of the hand when in a somewhat relaxed and open position (Figure 1). The handle surface should make full contact with the fingers and surface of the palm of the hand. A standard squeegee handle can be made more ergonomically correct by padding the handle with a compressible surface. This type of padding has been shown to reduce hand pain and fatigue significantly when used over time and may result in lower carpal tunnel pressures. Standard squeegee handles can be modified by adding compressible rubber grips. Handles/padding should be provided in varying widths and diameters to accommodate workers with different hand sizes.
Figure 1
NIOSH [1997]. Hazard control. Control of ergonomic hazards from squeegee handles in the screen-printing industry. Cincinnati, OH. U.S. Department of Health and Human Services, Public Health Service, Center for Disease Control and Prevention, National Institute for Occupational Safety and Health. DHHS (NIOSH) Publication 97-137.