ERGONOMIC EVALUATION OF POST BIOMECHANICAL EFFECTS OF LIFTING MAXIMUM LOADS USING MALE SUBJECTS

Abstract

Lifting tasks involving heavy weights have effect(s) on both the health and productivity of the person performing the task especially if ergonomic precautions are not adopted. When a person involved in manual materials handling sustains an injury in the course of performing a lifting task, it often results in wastage of both time and material resources. These usually have multiplier effect(s) on the profit margin of his employer. It is against this backdrop that an ergonomic evaluation of the post biomechanical effects of performing lifting tasks using male subjects was carried out. A field approach was adopted in the research involving six different kinds of lifting tasks. Places such as industries, warehouses and depots where manual lifting tasks are performed were visited. It was discovered that the right thigh is the prominent body part prone to body discomfort as a result of performing lifting tasks investigated in this research. The right shoulder was identified as more prominent to the aforementioned while the mid to lower back region of the body is outrageously the most prominent. A total of 209 male subjects performing lifting as their occupational tasks in the various places visited participated in the research. The average age, height and weight of\he subjects are 26.24 years, 169.59 cm and 65.08 kg respectively. The average weight of the materials lifted in the study is 32 kg. The workload rating by the subjects for the tasks they performed revealed that 51.20 % of them consider their workload to be HARD while 23.44 % opted for VERY HARD. A recommended maximum load chart was developed in the study to serve as a checklist for persons performing occupational lifting tasks. The chart shows the weight a person should lift as a percentage of his own weight. The recommended maximum load chart revealed that the expected maximum load that can be safely lifted by the subjects in this study is 16.25 kg against the 32 kg load lifted. The lifting signs developed in the study will serve as guide to people performing manual lifting tasks as their occupation