Evaluation and ergonomic design of workstations to increase productivity in a salt processing line

Abstract

The purpose of this research was to propose improvements in workstations to increase productivity on a salt processing line. The initial diagnosis revealed low labor productivity of 13 CMK bags/day-operator and an absenteeism rate of 13,8% due to MSDs, resulting in losses from unfulfilled orders. High ergonomic risks were identified, with maximum REBA scores of 11, OCRA Checklist values above 22,5, and load handling indices greater than 18 kg. In addition, noise levels reached 100,6 ± 2,1 dB, and 80% of workstations had insufficient lighting. Based on these results, improvement strategies were proposed following the hierarchy of controls. These included replacing manual operations with machinery, engineering controls for the design of a filling machine using SolidWorks, administrative controls, and the use of PPE. The improvement is estimated to be a decrease in ergonomic risk at all workstations, a 23% increase in labor productivity, and a 10% increase in total productivity. Finally, the feasibility and profitability of the project were demonstrated by a NPV of S/ 25 648,98, an IRR of 30,38%, and a B/C ratio of 1,51.