An Ergonomics Approach for the Design of Manual Materials-Handling Tasks

Abstract

The frequency, severity, and cost of manual materials-handling (MMH) injuries dictate that the design of these tasks and the assignment of employees to them ensure that the demands of the job do not exceed the capacity of the worker. This paper proposes the use of the job Severity Index (JSI) as a tool for job design and employee placement. The JSI is defined as the time- and frequency-weighted average of the maximum weight required by each task divided by the selected lifting capacity given the lifting task conditions. This paper illustrates the relationship between the JSI and the frequency, severity, and cost of MMH injuries. Procedures for job design and employee placement based on the JSI are discussed and examples of the use of the JSI in industry are given.

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References

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