Iranian Journal of Ergonomics

Background and Objectives: One of the most effective methods for managing ergonomic risk factors in the workplace is to involve employees in identifying and assessing ergonomic risk factors and ultimately designing and implementing interventions by themselves. Therefore, this study aimed to implement a participatory ergonomic program, focusing on the transfer of ergonomic knowledge to employees, and to examine the effects of interventions on the macroeconomic indexes.  
Methods: This semi-experimental interventional study was carried out in cooperation with all staff of one of the medical diagnostic laboratories in Isfahan (11 people) in 2017. A participatory ergonomic program was implemented based on the Occupational Health Clinics for Ontario Workers Inc. (OHCOW) Guide. Then, the differences in the level of macro ergonomic elements such as job satisfaction and increase in motivating potential score of employees were studied before and after the interventions resulting from participatory ergonomic program (OHCOW) in this work environment. The data was analyzed using SPSS 23.
Results: Job satisfaction before and after ergonomic interventions had no significant difference (a relative increase), but in one of the scales, namely organizational climate, there was a significant change (P=0.016). Also, the motivating potential score of employees after the intervention was significantly higher than before (P=0.013).
Conclusion: In this study, participatory ergonomics were used to improve some aspects of macro ergonomic elements. Based on the results of this study, participatory ergonomics can increase some job satisfaction scores and motivating potential score of employees. Finally, it is suggested that allocate a longer duration for intervention utilization.

Background and Objectives: Mental fatigue is a condition triggered by prolonged cognitive activity. Mental fatigue causes brain over-activity. This is a condition where the brain cells become exhausted, hampering person productivity, and overall cognitive function. The aim of this study was to assess students’ mental fatigue using brain indices.
Methods: The present descriptive - analytic study has been conducted on 20 students of the Faculty of Health mean age (SD) of 24.40 (3.73) years old in Ahwaz University of Medical Sciences (2019). To assess the performance of the participants, they were asked to study a text with spelling errors and correct those errors. This activity was performed in five stages, each lasting 15 min and EEG was recorded at all stages, and at each stage, the visual analog scale was completed by participants. Data analysis was done by SPSS 24.
Results: The results showed that the activity of alpha, beta, and theta signals in the first 15 minutes was 0.89±0.30, 0.70±0.33, and 1.19±0.36, and the last 15 minutes, 0.63±0.34, 0.55±0.26, and 1.03±0.34 respectively. Reducing the activity of the signals indicated there has been an increase in the amount of mental fatigue in individuals. Also, using visual analog scale, the individuals have acknowledged that they have experienced symptoms of mental fatigue. Finally, there was no significant relationship between students’ EEG and visual analog scale.
Conclusion: The results showed that alpha, beta and theta indices could be suitable indicators for evaluating mental fatigue. Also, mental fatigue can be one of the factors that affect the accuracy and performance of individuals, so that it can reduce their attention and efficiency.

Background and Objectives: The ethic-based culture is the predictor of ethical behavior and organizational citizenship behavior. Ethical culture enhances our awareness of our activities and can also increase our awareness of our bilateral commitments to the organization and therefore focus on what is important in an organizational setting. The present research aimed at investigating the relationship between the ethical culture with a tendency to ethical behavior and organizational citizenship behavior by examining the mediating role of the person’s organization in the staff of Urmia University.
Methods: This descriptive correlation study is a structural equation modeling model. The statistical population of this study consisted of all 503 high school graduates of Urmia University in 2018. Based on the stratified random sampling method, 217 individuals were selected. Standard questionnaires were used to collect information. Data analysis was performed using descriptive indexes and structural equation modeling method.
Results: Based on the results there is a positive and significant relationship between ethical culture with ethical behavior and organizational citizenship behavior. Also, the direct and significant impact of ethical culture on the individual-organizational adaptability was confirmed. The results also showed that the individual-organizational adaptability has a positive and significant relationship with ethical and organizational citizenship behaviors. In addition, the role of mediation of this variable (individual-organizational adaptability) in the relation between the ethical culture with two other variables (ethical and organizational citizenship behaviors) was also confirmed based on the findings of the research.
Conclusion: Based on the findings, it can be concluded that ethical culture directly promotes personal-organizational fit. In addition, confirming the mediating role of the individual-organization fit ethical culture has an indirect, positive and significant effect on ethical behavior and organizational citizenship behavior.

Background and Objectives: Given the increasing prevalence of smart phone usage, it can be considered as an important and significant issue in all aspects of human life. Therefore, the purpose of this study was to study the effect of duration of smartphone use on head and shoulders’ posture of young adults aged 20-35 years.
Methods: The statistical population of this study was young people aged 20 to 35 with smart phones who were resident of Kish Island in 2018. A sample of 50 people (25 men and 25 women) were selected voluntarily and purposefully. Low- user and High- user groups were identified by completing the form of addiction to smart cell phone, in assessing the status of upper limb, the shoulder position was measured by Scapular index and head position was measured by photogrammetric method technique and Kinovea software. Independent t-test was used for comparison of experimental variables between two groups. Data were analyzed with SPSS  22. P<0.05 was considered significant.
Results: The findings showed that there is a significant difference between upper limb posture in Low- user and High- user groups (P=0.033). There was also a significant difference in shoulder position between men and women (P=0.002). But regarding head positioning, there was no significant difference between men and women (P=0.436).
Conclusion: Thus, it seems that considering the significant difference between the two groups mentioned for upper limb posture, we can use the results of this study to inform, prevent and improve the upper.

Background and Objectives: In recent years, due to the rapid growth of metropolitan cities and the shortage of urban public transport means, including urban bus transportation, many people are forced to travel in a standing position when using these vehicles. This situation may cause pain and discomfort and non-collision injuries for passengers. The purpose of this study was ergonomic assessment of the sit-standing seat in passengers standing on urban buses.
Methods: To do this study, 8 young people with a mean age of 25.25±2.12 years were enrolled. For evaluation and assessing the effect of sit-standing seat two methods of surface Electromyography (sEMG) and Borg scale scores were applied in Fall 2018. The data was analyzed using SPSS 24.
Results: In all body parts, except for the hip, the mean scoring of Borg’s scale for perceived discomfort in sit-standing position was less than standing position. Also, the amount of contractile activity of the leg muscles in sit-standing position was significantly lower than the standing position (P<0.05).
Conclusion: Considering the results obtained from the Borg scale scores and the contraction activity of the leg muscles as a result of the use of the mentioned seat, which led to a reduction in the level of discomfort and the leg muscles contraction, it is recommended to apply the sit-stand seat instead of being in a standing position.

Background and Objectives: Musculoskeletal disorders cause about half of all work-related disease, and are the major cause of loss of time, increased costs, and labor injury. This study aims to evaluate the workload and its association with the prevalence of wrist disorders. It was carried out in the assembly workers of a manufacturing industry.
Methods: This cross-sectional study was conducted among 120 female workers employed. Theit mental workload, physical workload and prevalence of wrist MSDs were evaluated using the NASA-TLX, the OCRA method and the Nordic wrist and hand scan questionnaire respectively.
Results: The NASA-TLX showed that the physical demands and effort with mean scores of 78.79 and 78.37 were respectively the most important subjective mental workload (SMWL) scale. Also The results on the basis of the OCRA risk level showed that the highest right-hand risk was at risk level 3 and the highest left-hand risk was at risk level 1 .The Statistical analysis showed that OCRA risk levels and mean scale physical demands and efforts were significantly higher in those with wrist pain than those without pain (P<0.05).There was a direct correlation between the severity of the wrist pain with the OCRA risk index in both hands (P=0.001) and the total score of NASA (r=0.232, P<0.05).
Conclusion: It was revealed that mental load was high in assembly lines of the manufacturing industry and this result was also confirmed by physical evaluation. This study indicated that overall score of SMWL can affect the incidence of MSDs. That is why mental workload should be considered as a risk factor for MSDs.

Background and Objectives: Human errors in dialysis care can cause injury and death. One of the basic steps to increase reliability in this critical process is to analyze the error and identify the weaknesses of doing this process.
Methods: The present study is a descriptive-analytic cross-sectional study. The SPAR-H method was used to identify and evaluate the probability of human error in the dialysis process. The hospital had six dialysis department and 16 dialysis machines with two nurses in each department. Data collection was done by observing the dialysis process, interview with nurses, reviewing the documents, methods of work and work instructions.
Results: The present study showed that the probability of human error in the duties of a dialysis nurse is in the range of 0.02-0.44 (except for devices related to disorder), which is related to sub-duty preparing patient as lowest rate and sub-duty of the pump set-off as highest error rate.
Conclusion: To reduce and control the human error in nursing duties in the dialysis department, control measures should be done such as increasing the number of personnel, changing the time shift of nurses, and training, preparing and revising the instructions.

Background and Objectives: The statics and actions of people during daily activities plays a major role in the physical and mental health and dynamics of the community. Given that humans deal with different things in a day, it is necessary that they are adapted to his features of body. The main goal of this study is to design and construct tables and ergonomic chairs for cartography, in accordance with the physical dimensions of students.
Methods: In this research, one of the most used educational furniture, namely cartographic table and chairs, has been studied. After examining the satisfaction of this furniture, for ergonomic review and design in accordance with anthropometric dimensions, physical features of 160 students of art and 40 students of a technical and vocational school were measured. Then data was analyzed by SPSS 18 software.
Results: According to the results, about 70 percent of the students did not feel comfortable with the features of former chair and table, except for the length of the thigh. There was no significant difference between the different educational foundations in the vocational schools and finally, with the help of tonality features, the drawing table and chair were designed which except for the height of the sitting space, in other indices, there was a 100% correlation with the dimensions of the student's body.
Conclusion: In this study, there was a lot of dissatisfaction among students due to the lack of matching these educational materials with their physical dimensions which has caused physical, mental and psychological damage and poor quality of education. At the end of the study, through ergonomic design, matters of satisfaction, sustainability and reduced production costs and also the reasons for students' dissatisfaction with the drawing table and chairs is presented.

Background and Objectives: Most accidents are caused by unsafe behaviors or human errors. Safety experts have argued that with the increasing focus on human behavior, it can significantly reduce accidents. The aim of the present study was to examine neuroticism, safety efficacy and regulatory focus as predictors of unsafe work behavior of employee Bidboland Gas Refining Company.
Methods: The statistical population of the study consisted of all employees of operational and staffing departments of Bidboland Gas Refining Company in Khuzestan. The sample consisted of 273 employees who were selected using stratified random sampling. At first, the participants were divided into two groups, safe employees and unsafe employees by using Safety Behavior Scale (Salleh, 2010). Then to evaluate the variables studied, NEO personality characteristics (Costa & McCrae, 1992), safety efficacy (Brown, et al., 2000) and regulatory focus at work (Wallace & Chen, 2006) questionnaires were used. Data were analyzed through discriminant analysis and using SPSS 16 software.
Results: According to the results, unsafe behavior of employees can be predicted from neuroticism, safety efficacy and regulatory focus and its dimensions (prevention focus and promotion focus).
Conclusion: Neuroticism increases unsafe behaviors and safety efficacy and regulatory focus (prevention focus and promotion focus) decrease unsafe behaviors of employees.

Background and Objectives: Using appropriate methods for ergonomic risk assessment of musculoskeletal disorders has an important role in controlling these risks and providing workforce health. The purpose of this study was to evaluate the feasibility of applying WERA method to assess the risk of musculoskeletal disorders through its correlation with the results of QEC.
Methods: This descriptive-analytical study was performed on 72 employees of workshop sections of a modern brick industry. Data were collected using a Nordic questionnaire to assess the prevalence of musculoskeletal disorders in the past 12 months and WERA and QEC methods to ergonomic risk assessment of musculoskeletal disorders. Data were analyzed by SPSS 18.
Results: The prevalence of back, shoulder, neck and wrist disorders were 41.7%, 20.8%, 16.7% and 33.3%, respectively. Results of WERA showed that 88.9% of subjects had medium action level and 11.1% had high action level. In QEC method, 6.9% of subjects had exposure level ‘one’, 20.8% of subjects had exposure level ‘two’, 48.6% of subjects had exposure level ‘three’, and 23.7% of subjects had exposure level ‘four’. The correlation between QEC total score and prevalence of musculoskeletal disorders was (r=0.67, P=0.038). The correlation coefficient between the final scores of the two methods was (r=0.53, P=0.021).
Conclusion: Examination of the correlation between the mean scores of the two methods indicated a moderate correlation between them. Correlation between prevalence of disorders and QEC and WERA scores showed that QEC results were more consistent with Nordic results and it can be said that QEC method was more suitable for ergonomic assessment of musculoskeletal disorders risk for different tasks in this study.

Background and Objectives: Playgrounds play a very important role in the development of children's communities and their physical skills. If these spaces are designed according to safety standards, they can contribute to the better social and physical growth of children. The purpose of this study was to evaluate the safety status of children's playground equipment in Hamadan Luna Park according to the standards of the U.S. Consumer product safety commission (CPSC).
Methods: The present study was a descriptive and analytical one. The statistical population included a total of 600 persons, working in one of the regions in the Tehran Municipality. Of the 600 staff, a total of 255 were selected as the available sample group. The instruments consisted of the questionnaires, including the individual and occupational information, the Nordic questionnaire, the Walton Quality of work life, and the checklist of the ergonomic indices of the working environment for the administrative staff. In order to analyze the data, Student’s t-test and multiple regression analysis were used.
Results: The results showed that among the main playground equipments, the spiral slide has the highest ratio of 76.1% and the seesaws with 25% minimum compliance with the CPSC standard. Among the most commonly problems in this field the non-standard design of play equipment, incorrect assembly, installation and placement in use zones can be pointed.
Conclusion: According to this paper’s report, given the undeniable role of the safety of playground equipment in preventing possible harm to children, they must be secured and adapted to global standards.

Background and Objectivse: The employees of an industrial sector, especially the food industry, tackle many problems due to their type of job. Among these staff, non-standard working postures is known as a risk factor for musculoskeletal disorders. Musculoskeletal disorders affect the function and self-efficacy of these people and ultimately leads to a reduction in their performance. Therefore, in this case, research entitled: Study of risk factors of the ergonomic work environment and its relation with self-efficacy and job performance of employees of the food industry has been done.
Methods: A total of 202 people were selected as the sample group using a random sampling method. Then they completed the research questionnaires. The research tools consisted of Paterson's job performance questionnaire, Scherer general self-efficacy, Key Indicator method and a five-point body map questionnaire for assessing body organs discomfort and prevalence. Data was analyzed using SPSS 19.
Results: There was a significant difference between the level of risk of musculoskeletal disorders and their job performance and between the risk of musculoskeletal disorders and the prevalence of musculoskeletal disorders. The lower back showed the highest prevalence of musculoskeletal disorders. There was a significant difference between the levels of risk of musculoskeletal disorders with job performance and also between musculoskeletal disorders with job performance and self-efficacy. The results showed a positive and significant relationship between job performance and self-efficacy.
Conclusion: The results indicated the role of self-efficacy in preventing behaviors that lead to exacerbation of musculoskeletal disorders. This will ultimately be reflected in their job performance and both the individual and the organization concerned. Also, employing high self-efficacy staff can improve work performance and productivity and contribute to better production processes.

Background and Objectives: Sewing is one of the occupations where the prevalence of musculoskeletal disorders is high. Sewing conditions at the workstation have made tailors face musculoskeletal injuries in various areas of their body, particularly pain in the neck, shoulder, and upper back and even waist. The purpose of this study was to evaluate the effect of a workstation designed for tailoring considering the results of previous studies on the neck and shoulder muscles of users by electromyography.
Methods: In this interventional analytical study, the activity levels of four superficial neck and shoulder muscles (meridian, anterior deltoid, middle deltoid, posterior deltoid) were Electromyographed on 33 participants (male and female) at two new and custom designed workstations.
Results: There was a significant difference in the amount of muscle activity in the new and existing workstations (P<0.05). But there was no significant difference between the different modes of the new workstation.
Conclusion: All four muscles were less active at the new workstation than the conventional workstation, meaning that the designed workstation was able to reduce neck and shoulder muscle activity during work.

Background and Objectives: Bank staff do much of their work using computers, Their equipment and layout may put the body in an inappropriate position and lead to musculoskeletal disorders (MSDs), so this study aimed to determine the prevalence of MSDs in bank staff and its relationship with office tensions.
Methods: This descriptive cross-sectional study was performed on 173 employees of Melli Bank of North Khorasan Province. The prevalence of MSDs was estimated through CMDQ, Risk factors were estimated through ROSA and data were entered into SPSS 20. Then their relationship with each other and with the equipment layout was determined by Spearman test.
Results: The mean ROSA scores were 4.73±0.793 and 63.6% of the postures were in the intervention group. The mean CMDQ scores were 103.63±181.004. Spearman test showed a good correlation between ROSA and CMDQ results (P=0.021, R= 0.175). There was a significant relationship between work experience and prevalence of MSDs (P=0.037, R=0.159). Kruskal-Wallis test showed a significant relationship between education level and CMDQ scores (P=0.38). The most common disorders in the organs were neck (53.8%) and lower back (49.7%).
Conclusion: Given the correlation between the ROSA results and the CMDQ, they can be used together. The change should be considered immediately for persons who are in intervention group. The chair and monitor played a more important role in raising the ROSA score. Improvements should be made by providing an ergonomic chair as well as a proper layout of other equipment such as a monitor.

Background and Objectives: Macro Ergonomics is a socio-technical approach that deals with organizational, and work system design, as well as the design of human-machine, human-environment, and human-job interactions. Researches show that workplace macroeconomic’ conditions have undesirable effects on employees’ health, and hospital staff experience high levels of occupational stress and high prevalence of musculoskeletal disorders. This study aimed to investigate the relation between macroeconomic’ condition and prevalence of musculoskeletal disorders as well as outcomes of job stress among employees of hospitals affiliated to Urmia University of Medical Sciences.
Methods: This study was a descriptive cross-sectional study and 350 employees who randomly were selected from 5 hospitals participated in this study. Macro-ergonomic, Nordic and job stress outcomes questionnaires were used for data collection. Descriptive statistics, ANOVA and Chi-square tests were applied for data analysis.
Results: The findings of the present study indicated that out of 350 participants 217 (62%) were female and 168 were nurses (48%). Their mean age was 36.63 (±8.13) years and their average work experience was 11.53 (±7.65) years. The results of ANOVA test showed that the status of macro-ergonomics was significantly different in hospitals and hospital 1 had favorable condition. The majority of musculoskeletal disorder symptoms were reported in the neck (75.7%), hip, and waist (73.7%). The average score of job stress outcomes for the participants was lower than favorable limit. Macro-ergonomic’ conditions had significant associations with musculoskeletal disorders and job stress’ outcomes.
Conclusion: Based on the results of the current study, macro-ergonomic conditions had significant effects on musculoskeletal disorders and job stress outcomes. Interventional efforts should focus on organization and developing macro-ergonomic training programs to reduce musculoskeletal disorders and job stress and improve job conditions in hospitals.

Background and Aims: Ergonomics is associated with the study and systematic design of the workplace to improve human health and well-being. The health and well-being of employees are influenced by a variety of factors. Nature is a new paradigm in occupational ergonomics that has not been well explored in the main texts of ergonomics in relation to human well-being. Therefore, the main purpose of this study was to investigate the results of joining with nature on staff health, especially well-being in the form of a systematic review study.
Methods: By searching articles published from 2000 to 2019 in the field of Biophilic design, 25 articles were selected for the present systematic study based on the research criteria. Non-English language articles excluded.
Results: The results of this study showed that Biophilic design is associated with improved human well-being, performance, concentration and stress reduction.
Conclusion: Organizations, with the help of ergonomists, should consider such changes in the workplace, and nature-based solutions as strategic programs for improving well-being rather than merely applying a temporary strategy that changes the physical condition of a building or its landscape.

Background and Objectives: One of the major challenges that managers face in competitive organizations is the improvement of the performance and productivity of the organization and understanding the factors affecting them. The promotion of the organizational performance requires managers to focus on the organizational justice and employees’ motivation at work. The purpose of this study is to determine the relationship between organizational justice and organizational performance in the Health Center of Kermanshah Province.
Methods: The present work was a descriptive-analytic and correlation study. This study was performed on 166 employees of the Health Center of Kermanshah in summer 2019, selected by random sampling. Data were collected using two standard questionnaires: the organizational justice of Nihoff and Morman (1993), and the organizational performance of Hersey and Goldsmith (1980). Reliability of the questionnaires was assessed by the pilot study and Cronbach's alpha coefficient. Data analysis was performed using SPSS 16 software.
Results: The results showed that the average scores of the organizational justice and the organizational performance are 54.84± 16.92 and 140.54± 18.66, respectively. According to the results of Pearson correlation coefficient, there is significant relationship between the organizational justice and its dimensions with organizational performance (P<0.001). However, the procedural justice has the more potential to predict the organizational performance.
Conclusion: The organizational justice is an important variable, strongly affecting the organizational performance. Therefore, managers need to pay particular attention to the justice as an important motivating factor for employees in order to improve the organizational performance and productivity.

Background and Objectives: Using anthropometric characteristics in the ergonomic design of workstations can be useful in the prevention and reduction of musculoskeletal discomfort and in office-work environments. The purpose of this study was to determine the anthropometric dimensions of Hormozgan province gas department staff to design desks and chairs for computer work based workstations.
Methods: This is a descriptive-analytical study for measuring 36 anthropometric variables of 121 Hormozgan province gas company staff selected by cluster random method. After collecting anthropometric data considering ergonomic design criteria, dimensions of desk and office chairs are designed.
Results: Participants were 80.2% male and 19.8% female with a mean age of 35.11 and a standard deviation of 6.6 between 25 and 59 years. The mean and standard deviation of height measured was 170.7 and 8.06 cm, respectively. Anthropometric results are shown separately by gender and percentile in the tables. Dimensions of chair and office desk are designed based on obtained data.
Conclusion: The presented anthropometric desks can be used in future studies and designs. Also, the dimensional characteristics of the furniture provided can be a practical guide for designing and manufacturing office workstations.

Background and Objectives: Factors affecting one's job performance include job stress, job calling and burnout. The purpose of this study was to determine the causal relationship between job stressors, job calling and job burnout among employees of Hamadan University of Medical Sciences.
Methods: This descriptive-analytical cross-sectional study was performed on 378 non-faculty members of Hamadan University of Medical Sciences. Data were collected using Maslach Burnout Inventory, Job Stress Questionnaire (HSE-Q) and Dik's job calling. To investigate the relationship between variables, Structural Equation Modeling (SEM) method was used in AMOS version 24 software.
Results: The mean age of participants was 38.93 years. The components of job stressors and job calling had a positive and significant correlation with the components of job burnout (P<0.05). The measurement model was acceptable with the collected data. Job stressors indirectly and mediate the dimensions of presence and search of job calling are related to job burnout of medical university employees. The sum of squares of multiple correlations for job burnout variable was 0.56. This finding indicated that occupational stressors and job calling account for 52% of the variance in burnout.
Conclusion: Given the detrimental effects of burnout on employees, it is suggested that authorities reduce stressors such as the psychological and physical needs of the workplace, lack of support, job insecurity, and job calling.

Background and Aim: Undesirable lighting at work environment causes visual and non-visual effects on employers. The aim of this study was to compare the quantity and quality of combined and artificial lighting in daytime and its relationship with the indexes of mental performance.
Methods: This study was carried out at 65 rooms and on 81 employees randomly selected from different clusters. Measurement of lighting parameters was done using a spectrometer. To assess the cognitive function, the Pshycomotor Vigiliance Task (PVT) test and for the sake of visual comfort, alertness and sleep quality, the Conlone, KSS (Karolinska Sleepiness Scale) and PSQI (Pittsburgh Sleep Quality Index) questionnaires were used respectively.
Results: Most artificial sources used in the rooms included fluorescent lights in different shapes and colors. The average indexes of combined lighting was more than artificial lightings (P<0.001). Visual comfort was correlated with high color temperature (P=0.006, r = 0.315). The employees with natural lighting had less visually impairment. The sleep quality of the subjects was related to the type of work environment lighting (Chi²=0.59, P=0.44). Alertness of subjects exposed to high color temperature or natural light was better at 8 and 11 hours. The results of cognitive performance test showed no significant difference between different lighting conditions.
Conclusion: Using natural light or artificial lights with adequate illuminance and high correlated color temperature can increase the alertness and visual comfort to some extent and improve the sleep quality of day staff employers.