The effect of operating height and holding mode on holding capacity for female subjects

Abstract

The holding task is a very common manual human activity, but it has not been investigated previously by psychophysicists. Eight females participate in this study. A psychophysical method is used to determine how the operating height (elbow, shoulder, and overhead heights) and the holding mode (non-dominant, dominant, and two hands) affect the maximum acceptable holding weight (MAWH), heart rate (HR), and rating of perceived exertion (RPE), when holding a box against a vertical surface. The operating height and the holding mode have a significant influence on the MAWH. However, the HR is not significantly influenced by the operating height and the holding mode. The overall RPE values are significantly influenced by the holding mode. The most stressed body parts are the arms, wrists, and shoulders. In general, these findings indicate that the holding task should be performed using two hands or ergonomically redesigned as much as possible.

Keywords:

• manual materials handling
• holding task
• maximum acceptable weight of holding
• psychophysics

Acknowledgement

This research was supported by the National Science Research Council, Taiwan, ROC project No. NSC 93-2213-E-211-007.