Article Info Background: Musculoskeletal disorders (MSDs) are one of the most common work-related illnesses, which lead to high costs and a reduction in labor productivity. The aim of this study was to investigate the relationship between MSDs with mental workload (MWL) and occupational fatigue among the office staff of a communication service in Tehran, Iran, in 2017. Materials and Methods: This descriptive study was conducted on 94 staff of a communication service company in June 2017. The data collection tools included Rapid Office Strain Assessment (ROSA), NASA Task Load Index (NASA-TLX) questionnaire and Swedish Occupational Fatigue Inventory (SOFI). Data analysis conducted using descriptive statistics and one-way ANOVA test in SPSS software. Results: 73% of the participants were women with mean age of 28.25 ± 3.40 years and the remaining participants were men with mean age of 26.91 ± 4.60 years. According to the results of the Nordic questionnaire, the highest pain was observed in the neck (65.94%) during the last year. According to the results of the ROSA, 71% of the participants were at the warning risk level and the need for ergonomic interventions. In addition, the relationship between occupational fatigue and its subscales with MSDs was significant in all cases (P < 0.001). Finally According to the results, the participants' MWL was high. Conclusions: The results of the present study showed that high workload and occupational fatigue cause MSDs, and intervention is necessary in these individuals.

Introduction: The importance of assessing and identifying ergonomic risk factors in the workplace among office workers has increased with the increase in occupational tasks of computer and increasing the risk of physical and mental disorders among its users. One of these factors is the usability of computer hardware and software. The purpose of this study was to evaluate the applicability of office automation software and to measure the fatigue and burnout of employees in an office and determine their correlation. Methods: In this study, in one of the health centers of Tehran City, staff fatigue, burnout and their use of office automation software using multidimensional job fatigue inventory (MFI-20), maslach burnout inventory (MBI), and the standard questionnaire was used to evaluate the usability of the software. Data were analyzed by SPSS 23 software. Results: The findings of this study showed that automation software was very useful for most users. According to the findings of this study, there was a significant negative correlation between software usability and emotional exhaustion dimensions, the reduction of personal inadequacy, general fatigue, and physical fatigue with correlation coefficients of -0.228, -0.511, -0.372 and -0.287, respectively.. The greater the usability of the software, the lower the level of employee fatigue and fatigue. Conclusion: The applicability of job software is effective in burnout and fatigue of employees. Therefore, the usable design of such web-based software should be considered by office systems and software developers