**1. Introduction**

A manufacturing organization is a convoluted human–machine–environment organization system [1] Although the primary objective of such systems is to provide continuous improvements in quality and productivity, thereby increasing profits, meeting this objective largely depends on the wellness of employees and their willingness to actively engage in production activity [2]. Worker fatigue and work-related musculoskeletal Disorders (WMSDs) can lead to losses in overall productivity and efficiency [3]. WMSDs also accounted for 4.1 million early deaths in 2015, an increase of 46% since 2000 [4]. WMSDs have contributed to almost 400,000 injuries, costing industries over USD 20 billion per year. In 2019, 9440 cases of work-related musculoskeletal disorders (WMSDs) were reported in Korea, representing an increase of 2725 cases (40.6%) from the 6715 cases reported in the previous year. The cases accounted for approximately two thirds (67.3%) of all occupational diseases in that year [5]. The study of ergonomics plays a pivotal role in the design and development of conducive working environments that optimize the wellbeing of operators, thus increasing productivity safely [6]. Recently, Indian manufacturing industries have undertaken initiatives to redesign their workplaces to overcome various occupational injuries and musculoskeletal disorders (MSD) [7].

**Citation:** Vijayakumar, K.; Robert, P. Human Factor Index Measurement Using an ISM-SEM-Fuzzy Approach. *Sustainability* **2022**, *14*, 7635. https:// doi.org/10.3390/su14137635

Academic Editors: María del Carmen Valls Martínez, José-María Montero and Pedro Antonio Martín Cervantes

Received: 21 April 2022 Accepted: 14 June 2022 Published: 22 June 2022

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**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

Recent studies have explored the applications of ergonomic tools such as the Strain Index (SI), the National Aeronautics and Space Administration Task Load Index (NASA TLX), the Occupational Repetitive Actions Index (OCRA), the Rapid Upper Limb Assessment (RULA), the Ovako Working posture Analysis System (OWAS) checklist, and the Rapid Entire Body Assessment (REBA) to improve occupational health and safety in the areas of machine design, task design, the working environment, and facility design. These tools and techniques to derive benefits based on the theory of ergonomics require considerable time and energy to implement. Present methods of evaluating postural risk are based on observational techniques that requires an ergonomic analyst to observe the work in real-time or from recorded video to manually segment the relevant body parts and evaluate the risk associated with the posture [8]. Due to human error, however, these techniques produce results with low consistency and repeatability, both of which can be reduced or eliminated by using advanced technologies [9]. All the risk assessment methodologies are used to evaluate the physiological level of risk that was associated with performance of the job.

This study aims to develop a human factor index measurement tool that includes physiological, psychological, environmental, and safety risk considerations based on how these risks are interrelated. Moreover, the use of several indicators in a study requires that these indicators themselves be understood and are easily measurable. However, these limitations have not been addressed in many studies. The remainder of this paper is organized as follows: Section 2 presents the research background in the areas of ergonomic risk evaluation and assessment. The proposed methodology for workplace ergonomic assessment is described in Section 3. The conceptual framework and analysis are presented in Section 4. Finally, the results of this study are reported in Section 5.
