مجله مهندسی بهداشت حرفه ای
سال پنجم شماره 4 (زمستان 1397)

Considering the importance and high prevalence of musculoskeletal disorders, this study aimed to investigate the role of mental workload, fatigue, and sleep quality in the development of musculoskeletal disorders. This study included 243 employees working at Borujerd health center. The participants were selected based on simple random sampling. The data were collected using the Cornell Musculoskeletal Disorders Questionnaire, Sophie Fatigue Questionnaire, and Pittsburgh Sleep Quality Questionnaire. Moreover, the Subjective Workload Assessment Technique was utilized to evaluate the mental workload. The data were analyzed using SPSS software (Version 18) through the Pearson correlation coefficient, the Chi-square test, and regression analysis. According to the results of this study, back pain was ranked as the most prevalent disorder. The results of the correlation analysis showed a significant association between mental workload and fatigue with musculoskeletal disorders (P≤0.05). Moreover, a significant relationship was observed between sleep quality and musculoskeletal disorders (P≤0.05). It can be concluded that reduced workload and fatigue, as well as improved sleep quality, can decrease the risk of musculoskeletal disorders among the staff.

In the last few decades, organizational factors have become the leading indicators of occupational health and safety (OHS) performance in industries. ELMERI is a simple and cost-effective method for monitoring OHS performance in the manufacturing industries. Regrading this, the present study was carried out to evaluate the safety and health performance in a steel industry by using the ELMERI index. In this cross-sectional descriptive study, the safety and health conditions of the workplace were evaluated by Health and Safety Executive (HSE) specialists using the ELMERI index. The ELMERI index covered safety behavior, workplace hygien and housekeeping, machinery safety, occupational health, ergonomics, walkways, fire safety, and first aids. Finally, ELMERI index was examined based on the findings. The results of this study demonstrated that an ELMERI index of 69% is indicative of a moderate performance. Safety behavior, workplace hygien and housekeeping, machinery safety, occupational health, ergonomics, walkways, fire safety, and first aids were determined as 75%, 64.4%, 80.5%, 51.4%, 66%, 75%, and 79.6%, respectively. A common feature for goal setting and a real-time indication of OHS performance is the use of the ELMERI method. The ELMERI method fills the gap between management activities and accident-based indicators in OHS management systems. The results of this study enable managers to make the best decisions to provide and implement preventive measures based on indicators and events by the evaluation of performance safety.

Technological progress and application of the modern surgical techniques have led to more interest in laparoscopy by surgeons and patients. As a result, surgeons might potentially have more complications due to this procedures. Knowledge and practice of ergonomics principles can greatly reduce these problems. With this background in mind, this study evaluated the ergonomic issues in laparoscopic surgeons. This cross-sectional study was performed on 50 laparoscopic surgeons employed at Tehran University of Medical Sciences, Iran through the census method. The data were collected using the researcher-made survey questionnaire regarding ergonomics in laparoscopic surgery. All the data were analyzed by descriptive statistics utilizing the SPSS software version 21. The findings of this study showed that most of the surgeons were not satisfied with the hand-held instrument (72%) and foot pedal (38%). Moreover, 48% and 38% of the surgeons expressed that neck and shoulder discomfort may arise due to inappropriate position of the monitor and unadjusted height of the operating table, respectively. However, only 24% of the subjects were aware of ergonomics guidelines concerning laparoscopic surgery. According to our results, the surgeons stated that it is necessary to understand the ergonomics problems of the work environments with the aim of finding effective interventions. Therefore, taking into account the interactions between the surgeon and the operating room, in addition to improving the knowledge about ergonomics principles can play an important role in reducing the occupational injury in the surgeons.

Currently, photocatalysts have become a major focus of research in physics, chemistry, and surface engineering. It is hoped that this science help to solve various environmental problems.  This study investigated the effect of ultraviolet lamp type on the removal efficiency of xylene utilizing the fixation of TiO2 nanoparticles on the activated carbon absorber and passing different concentrations of polluted air through xylene. In this experimental study, after the fixation of nanoparticles on activated carbon, the produced catalyst characteristics with the specific surface area were determined using Brunauer-Emmett-Teller (BET) analysis and scanning electron microscope (SEM). A dynamic concentrator system was used in order to produce xylene vapor. Moreover, the photocatalytic removal efficiency of xylene with three inlet concentrations of the pollutant was studied under ultraviolet rays in the wavelengths of A and C regions. The results of BET analysis and SEM images showed that nanoparticles were well fixed on the surface of activated carbon. Moreover, the photocatalytic removal efficiency in the concentrations of 50, 100 and 300 ppm was equal to 87.8%, 98.9%, and 90.8%, respectively. In addition, no significant difference was observed between ultraviolet A and C regarding photocatalytic removal efficiency of xylene. According to the results of this study, the inlet concentration of the pollutant had an effect on its photocatalytic removal efficiency. However, there was no significant difference between ultraviolet A and C regarding photocatalytic removal efficiency of xylene.

Lack of anthropometric data in order to design workstations and equipment can cause work-related injuries; therefore, it is necessary to create anthropometric database. The aim of the present study was to evaluate the appropriateness of hospital equipment ergonomic indices to female nurses’ anthropometric dimensions in one of the teaching and therapeutic hospitals of Sabzevar, Iran. In this cross-sectional study, 96 female nurses were selected using convenience sampling method. In the first phase, the participants completed the demographic questionnaire and body map checklist. Then, in addition to height and weight, 14 anthropometric dimensions of the subjects were measured by an expert in ergonomics using Calipers. Furthermore, in order to compare the participants’ ergonomic dimensions with equipment dimensions in hospital, the dimensions of the ten most used equipment in the hospital were measured. The data were analyzed by SPSS software (version 17) using the Chi-square test, Mann–Whitney U test, Fisher's exact test, and Student's t-test. P-value less than 0.05 was considered statistically significant. The findings of the present study indicated that high prevalence of musculoskeletal pain among female nurses, especially in the neck, waist, back, shoulder, and knee regions were reported as 73.7%, 70.62%, 69.38%, 14/55 %, and 32/48%, respectively. Moreover, the investigation of the participants’ anthropometric dimensions and the measurement of equipment dimensions revealed that there was no appropriateness in many aspects, such as access limit, mid-shoulder height, standing elbow height, with the equipment, such as serum holder, drug trolley, medicinal shelf, hospital bead, and nursing station. Despite the differences in the physical dimensions of female nurses, the equipment was not proportional to the participants’ anthropometric dimensions in the present study. It is necessary to consider this issue in order to reduce the incidence of musculoskeletal disorders.

Mental fatigue usually occurrs as a result of long-term cognitive activities. Mental fatigue could have important effects on the daily lives of healthy people. Therefore, the purpose of this study was to estimate mental fatigue and its impact on staff performance. This descriptive analytic study was performed on 10 staff with a mean age of 36±6.19 years. To evaluate the performance of the participants, they were asked to read a text with spelling errors and then correct them. This test was performed in 5 steps of 15 min during which electroencephalography (EEG) was performed. At each step, the Karolinska Sleepiness Scale (KSS) was completed by the staff. The data were analyzed statistically by the repeated measures ANOVA and Pearson correlation coefficient. According to the results, the brain waves decreased during the experiment, which was indicative of increased mental fatigue. The EEG was recorded as 213.14±59.98 and 77.68±21.68 in the first and last 15 min, respectively. In addition, the participants were reported their fatigue by KSS, based on which the performance of the participants was shown to decrease from 27.3±4.53 to 17.5±5.19. The EEG facilitates the investigation of mental fatigue over different periods of time. As the results indicated, mental fatigue caused by long-term cognitive activities could result in the reduction of the accuracy, focus, and consciousness of the staff. Finally, increased mental fatigue led to the recution of the quality of individuals’ performance.

Approximately, half of the occupational accidents are associated with the construction industry in Iran. Therefore, the factor analysis of risk variables affecting occupational injuries in the construction industry can lead to understanding and reducing the rate of injuries in these projects. The purpose of this study was to identify the risk factors affecting the types of injuries in construction projects based on factor analysis. This field study was conducted on 65 active construction projects. The collected data included 55 injuries that were analyzed in SPSS software (Version 22.0) based on exploratory factor analysis and confirmatory factor analysis. The most frequent type of injuries regarding the order were spinal cord injury (41.2%), cuts (32.4%), organ failure (17.6%), and multiple scars (8.8%). Based on exploratory factor analysis, 26 indicator variables were classified in six groups of latent factors, including individual, occupational, unsafe conditions, unsafe acts, the type of injury incidence, and the type of injury. The findings of the confirmatory factor analysis of latent factors showed a significant correlation within these factors (P<0.05). The goodness of fitness of the model was evaluated as good (RMSEA=0.663). The findings of the present study indicated that the incidence of injuries in construction projects can be due to the interaction between different factors and indicator variables. In addition, the results of factor analysis in this study indicated a difference between the effect of each of the indicator variables and latent factors.

Industrial estates have been described as highly prone to fire incidents. According to the baseline studies, more than 85% of the industrial accidents occurring in industrial estates during the 80s and 90s were fire incidents affecting more than one factory in 10% of the cases.   After the identification of 30 high-risk industries in Abbasabad industrial estate, a fault tree was designed using the hazard and operability analysis (HAZOP). In the next stage, the weak links in the system were pinpointed using quantitative and qualitative analysis and Bayesian network. The failure rate of each area was predicted using the available data and experts’ opinions, and then calculated using the fuzzy logic and Monte Carlo methods. The data were analyzed in the Crystalball software. After the analysis of the risks, the critical risks were identified and filtered using the Bowtie method, and then subjected to the management process. The consultation with industrial experts during the HAZOP process and application of filtration resulted in the identification of 15 major incidents, 9 and 6 events of which were probabilistic and fuzzy, respectively. The risks were rated based on the experts’ opinions and the given model; in this regard, the foam and paint industries gained the highest modeling score. The sensitivity analysis of failure probability revealed that the industries using or producing materials with a low flammable point have a higher risk; therefore, more attention should be paid to these industries to prevent the fire incidents. The application of the results of this study in the development of the required guidelines and trainings for the industrial managers resulted in a decrease in the number of accidents in Abbasaabad estate.