مجله ارگونومی
سال دهم شماره 2 (تابستان 1401)

Providing safety for human resources in the industry is very important. Safety shoes are one of the most common PPEs that protect the foot against potential hazards. This study aimed to evaluate the discomfort and usability of safety shoes in different industries of Mazandaran province to find gaps in the quality of design and improve the design of safety shoes.

This was a cross-sectional study and was conducted in 2021.This study included employees of 11 different industrial companies that used seven safety shoe brands. They answered two researcher-made questionnaires, LPD (discomfort and general satisfaction) and SFUQ (usability). Data analysis was performed with Spearman rank correlation coefficient while Pearson correlation coefficient, and ANOVA test were also performed.

In total, 226 men with a mean age of 36.33 ± 7.4 years were included in this study. The participants reported the lowest usability for the brand G (3.3 and 3.99), and the least discomfort and the most usability index with the brand A (1.2 and 5.35). Overall, the highest satisfaction was reported for brand A and the lowest satisfaction to brand G.

The findings of this study showed that the main problem in comfort and usability is probably related to shoe molds because the manufacturers of safety shoes import molds from abroad that do not fit the anthropometric characteristics of Iranian users’ feet.

Psychological parameters are among the most important components in determining the job performance of employees in the workplace and can be strongly affected by the epidemic of infectious diseases like COVID-19. The aim of this study was to investigate the effect of COVID-19 pandemic on mental workload and Occupational burnout of medical staff in Iran.

This case-control study was performed among the healthcare staff of two hospitals in Tehran province in 2021. All employees working in two hospitals were included by census method. The total number of people studied was 412 personnel. NASA-TLX and Maslach Burnout Inventory questionnaires were used to assess mental workload and burnout, respectively. Data were analyzed using Independent t-test and Chi-square.

The present study results revealed that the mean age, work experience, daily working hours, and body mass index of the studied employees were 36.70 ± 11.48 years, 12.53 ± 7.13 years, 9.64 ± 3.13 hours, and 23.89 ± 4.73 kg/m2, respectively. There was a significant difference between the two groups of cases and controls in the values of mental workload (P = 0.011) and burnout (P = 0.001).

The present study's findings revealed that the prevalence of COVID-19 could increase the values of mental workload parameters and burnout of health care personnel in medical settings. Therefore, control measures and psychological interventions to improve healthcare personnel's mental and physical health during the COVID-19 epidemic are mandatory.

Undoubtfuly, people spend a significant portion of their time in workplaces. Many factors affect the health and well-being of employees. The present study aimed to identify the architectural problems of the environment by examining the symptoms of Sick Building Syndrome and ranking the parameters influenced by five physical factors (thermal comfort, noise, lighting, layout-ergonomics and decoration).

The present descriptive-analytical research was carried out in the summer of 2021. The statistical population included 52 employees of Urmia Engineering Organization Building which is based on Morgan's table and a sample size consisting 46 people was randomly selected. The required data were collected through a questionnaire and analyzed using descriptive statistics (frequency, percentage, mean and standard deviation) and Friedman test.

Considering the average ranks, symptoms of fatigue (4.47), muscle pain (5.47), headache (5.87), high stress (6.14) and poor concentration (7.45), along with some defined parameters for each of the factors, including overcrowding and lack of speech privacy (78.12%), the noise of people's conversation (62.93%), improper workplace temperature in winter (58.59%) and summer (49.91%), inappropriate placement of uses and allocation of inadequate space for people and equipment (49.91%) played the most significant role.

The results indicated that the inefficient design of the environment and non-observance of ergonomic principles as a result of unprincipled renovations regardless of the nature of the work and its requirements, inappropriate placement of uses, the non-standard distribution of employees in an inflexible environment, lack of speech privacy and crowding were identified as the most important causes of the symptoms.

Work-related musculoskeletal disorders are multifactorial conditions that result in time loss, disability, and increased economical costs. The aim of the current study was to evaluate the role of the physical, environmental and psychosocial factors in the development of musculoskeletal disorders in workers in the production and assembly of auto parts in Qom city in 2021.
In this cross-sectional study, 211 participants through an inconvenience sampling method entered the study. The demographic characteristics of participants and the prevalence of musculoskeletal disorders were assessed by a self-report questionnaire and the Extended Nordic questionnaire, respectively. The mental workload was evaluated by the NASA-TLX index and the physical, environmental and psychosocial risk factors were evaluated by the Structured Multidisciplinary Work Evaluation Tool (SMET). The binary logistic regression method was used to show the role of the different risk factors in the development of MSDs.
Participants had an average age of 33.9 years (SD = 6.9). The lifetime prevalence of MSDs was obtained at about 77.72% in at least one area of the body. The neck, back, and shoulder areas were the most common regions. Gender, smoking history, surgery history, age, past surgery history, and sports history were most effective in the development of MSDs. In addition, subscales of mental workload play a role in causing pain in the shoulders, upper back, back and knees. SMET subscales play an effective role in the neck (OR = 1.396), upper back (OR = 1.663), hip, and knee, wrist/hand, and ankle/foot pain.
According to the role of various factors in developing disorders, the physical, psychosocial, and environmental factors should be considered simultaneously in planning preventive programs and ergonomics interventions.

Inappropriate sitting posture on bench can contribute to pain and musculoskeletal disorders in students. Hearing and vision disabilities may be the cause of inappropriate sitting postures among students. Therefore, the aim of the present study was to compare the risk of musculoskeletal disorders in normal and students with hearing abnormalities in Ilam city.
Twenty students with hearing abnormalities (case) and 40 students with normal hearing (control) from primary schools in Ilam city of both genders were randomly included in the study. The worst recorded sitting posture of students on the bench was evaluated by the RULA method. Digimizer software was used to survey the body angles of the students while sitting on the bench. The used for analyzing the obtained data in 95% confidence interval.
The results of posture evaluation showed that there was a significant difference in rula scores between case and control groups (P = 0.001). Deviation from the natural angles of the body in the case groups was more than the control group (P < 0.001), which has a direct and significant relationship with the increased risk of musculoskeletal disorders.
Musculoskeletal disorders possibility incidence were more common in students with hearing abnormalities compared to typical students which was due to an increase in deviation from the natural angles of the body and inappropriate postures. Given the limitation of the sample size, the present study recommends further research with the same goal and encourages interventional studies to correct the posture of hard of hearing students.

Risk-taking is a personality trait which plays a part in the occurrence of work-related accidents. For this reason, people who are highly risk-taking whose decision might cause accident should not be employed in critical situations. The purpose of this survey was to design and verify the validity of the risk tolerance questionnaire, suitable for control room operators, through examining the event related potential (ERP).
At first, the questions were selected from reliable scientific resources based on the conceptual model. The questions of the initial questionnaire were selected based on face validity, and then the questionnaire was filled out by 178 control room operators. At the next step, the best questions of the questionnaire were extracted using exploratory factor analysis (EFA). In terms of reliability, 42 individuals of the study group refilled in the questionnaire again after three months as a test-retest. The ERPs were assessed using electroencephalography along with Balloon Analogue Risk Task (BART). The correlation coefficient calculated between the ERPs, and risky behaviors, and questionnaire scores.
One factor and 13 questions were identified as the best questions regarding EFA. Cronbach's alpha was 0.91. The Spearman correlation coefficient was calculated between the questionnaire score and risk-taking behavior as well as between the questionnaire score and P300, which was 0.38 (P = 0.01, η2 = 0.70) and 0.63 (P = 0.01, η2 = 0.99), respectively.
The Operator control Room Risk-Taking (ORTQ) questionnaire consists of 13 questions which can be used as an appropriate tool to assess the risk-taking trait in control room operators and also for research purposes. This questionnaire has got three personality dimensions including risk-taking nature, impulsivity and venturesomeness.

Female music students report a higher prevalence of musculoskeletal pain compared with male music students. Incorrect posture while playing a musical instrument, is a key factor causing musculoskeletal pain in this group. The aim of this study was to investigate the prevalence of play-related musculoskeletal pain and related factors among female music students in Tehran.
A cross-sectional study was conducted among 243 female music students from October 2021 to November 2021. Data was collected using a self-report questionnaire, Numeric pain rating scale and Nordic Body Map respectively. Participants’ posture was assessed using theRapid Entire Body Assessment (REBA) checklist. Correlation and chi-square tests were applied to obtain the relationship between the presence of musculoskeletal pain and posture. A significance level of 0.05 was considered.
Of the 243 surveyed female music students, 65% (n = 80) reported at least one symptomatic area in the last week. The neck (33.7%), shoulders (24.7%), lower back (23.9%) and wrists/hands (22.6%) were most often affected. Participants who were older or had incorrect posture, have reported musculoskeletal pain significantly (P = 0.002 and P = 0.001 respectively). In addition, there was significant relationship between types of instruments with pain (P = 0.018). There was no significant relationship between the history and duration playing and educational status with pain.
It can be concluded that musculoskeletal pain was a major health problem among female music students. Educating about correct posture in music conservatories could be important in prevention and treatment of such disorders in this group.

The challenges that have been raised today, such as changes in population structure, diverse workforce, mass production, and automation of production, indicate the need to review production systems. Classical ergonomic solutions are no longer suitable for carrying heavy loads and repetitive activities. By supporting workers to reduce physical and mental stress, human-centered assistant applications (HCAAs) should solve this problem. The technical problems of the exoskeleton have been investigated in many scientific studies, but its effect on the human user has not been paid much attention to. So, this study reviews the studies that have examined industrial exoskeletons from the ergonomic point of view
Papers concerning exoskeleton in ergonomic studies are reviewed using Scopus and PubMed databases. The selected papers were published in the reviewed journals from 2014 to 2021. Books, conference papers, and reports are not included in this study. In the present study, only official scientific journals in English are reviewed, and the references obtained from the search are screened by the title and abstract. The full text of the papers is checked if the abstract does not contain enough information. Those papers that met the inclusion criteria are listed in this review.
Studies on ergonomic industrial exoskeletons account for a small share of studies on industrial exoskeletons. From 2012 to the time of conducting this study, 96 studies were found on industrial exoskeletons, of which 10.41% design or evaluate industrial exoskeletons from an ergonomic point of view. This is very small compared to the studies on exoskeleton conducted since 2012 and only about 0.4% of the studies.
The reviewed studies emphasize the facilitation of the successful use of exoskeletons in occupational structures by considering at least three dimensions (physical requirements, task performance, and usability), all of which can contribute to determining the potential efficiency of exoskeletons in the work environment. Due to the potential of this technology, more studies should be conducted in the future to cover some of the identified challenges and compare the exoskeleton design methods under more diverse and more realistic situations.