An Ergonomic Evaluation of a Job (Engine Mounting on Frame Body) In an Automobile Industry with Post Counter Measure Assessment Study

Abstract

Introduction & Objective: Even after automated industrial operations, manual handling is still evident with development of physiological fatigue alongwith ergonomic risk factors which invariably reduces human performance capacity. A cross-sectional scientific study was conducted in an automobile industry to assess physiological strain & ergonomic risk factors with an aim to make job comfortable & less risky.

Method: Study was conducted on 8 randomly selected employees of frame assembly section in an automobile industry. Job was manual unloading of automobile engine weighing 30 kg from conveyor tray, carrying it to another conveyor 2 meter apart & mounting on frame body. Resting HR, BSA & BMI of the workers were computed. Peak HR, oxygen saturation & later, recovery HR was recorded. NIOSH lifting index (LI) & RULA score for postural stress were assessed.

Result: Work-site dimensions of conveyor tray carrying engines- vertical height 52 cm from ground, horizontal distance 15 cm & frequency approx. 3/ min. Physiological work stress assessment (peak heart rate, oxygen uptake & energy expenditure) were 129.5±7.07 beats/min, 1.27±0.15 lit/min & 6.42±0.71 kcal/min respectively. Physiological recovery was 98.95±11.47, 91.10±10.23 & 83.70±7.35 beats/min. Mean oxygen saturation was 98.12% & mean resting heart rate 74.63 beats/min. LI was 4.04±0.53 and mean postural stress through RULA score was assessed to be 4.55±0.42

Conclusion: Physiological strain and postural strain were high. The cause of high RULA score & LI could be ascertained to job at shoulder height; vertical factor of LI was primarily responsible for which recommendation was conveyed for worksite design modification (subsequently done & recorded).