ABSTRACT

This case study examined several employees who experienced hand pain. This problem occurred at a midwestern chemical manufacturing plant in the laboratory of the quality control department. This facility employed over 3,000 employees including 1,275 management and research staff. The employees of concern in this study reported the onset of hand and wrist pain after a large number of samples had been drawn and tested. An ergonomic evaluation was conducted including a task analysis and the leading contributing factor was determined to be the position of the hand during sampling and the frequent use of a pipette bulb. An automatic pipettor and alternating the use of each hand was recommended to eliminate this problem. A trigger finger pipettor was used for a short time, but it resulted in more pain in the employees than the manual pipette so its use was discontinued. This apparently was due to the design of the automatic pipettor which required the depression and constant gripping pressure of the “pointer” or “trigger” finger when drawing or delivering a sample aliquot. Rogers (1983) reports that when the fingers apply force to activate switches, pressure increases in the skin and joint area of the hand. The employees took a varying amount of time off of work to recover from their injuries.