IRAN OCCUPATIONAL HEALTH JOURNAL
Year:2018 | Volume:14 | Issue:5 |Papers Count:18

Background and aims: Ethylbenzene (EB) is one of the most hazardous carcinogenic VOCs that is used or produced in various industries. Thus, it is important to reduce its use and control its emissions. The aim of this study was to determine the effectiveness of MnO2/Al2O3/Fe2O3 nanocomposite coated on HZSM-5 Zeolite for the removal of ethylbenzene vapors.Methods: Nanocomposite coated on HZSM-5 zeolite was synthesized by the sol-gel method, and its morphological characteristics were determined by XRD, FTIR, and SEM.We investigated the effects of the initial concentration of contaminant, relative humidity, and residence time on the performance of the nanocomposite for the control of ethylbenzene. The Response Surface method was used to estimate the main effects and these variables and their interactions so that we could optimize the number of experiments. The experiments were designed using Design Expert software, version 9.Results: The result showed that sizes of the Nano composite particles were less than 80 nanometers. The optimum condition for the removal of EB was found to be in 50% relative humidity, 19 s residence time and an initial concentration of EB of 300ppm. For this condition the nanocomposite removed 98.95% of the EB vapors.Conclusion: The nanocomposite provided high efficiency removal of EB from the gas phase or the conditions at which the study was conducted. The advantages of using the nanocomposite for this purpose include the reaction at room temperature and the ability to remove high concentrations of contaminants. The results of this study showed coating nanocomposites on HZSM-5 Zeolite provide an effective adsorbent for the removal of EB from the gaseous phase.

Background and aims: The job safety is one of the necessary aspects of efficiency in humane resource management of every organization, and if organizations were able to reduce the rate of job accidents and undesirable stress, then the performance of workers would become more efficient.Hence, job rotation is as good as a rest to increase efficiency. The aim of this research is to design an appropriate job rotation system in order to reduce job risks in terms of ergonomic risks of jobs.Methods: This research is aimed to design a job rotation system by using a mathematical modeling approach in which in addition to satisfying employer needs, it reduces ergonomic risk of jobs. The research method in this research is application in terms of goal, and is mathematical descriptive in terms of method, which includes: (1) problem extraction, (2) modeling, (3) model solving, (4) model verification, and (5) model implementation. The aim is to all of the risks R_ijt is assigned to n workers such that maximum risk of all workers are minimized (problem extraction). According to conditions and constraints of system, the problem is modeled as a linear programming model. The parts of this model includes objective function of minimization of maximum job risk of human resource, structural constraints of problem (each job should be assigned just to one worker at any time, and each worker should occupy just one job), parameters (n workers, n jobs at time interval T, jobs risks R_ijt), and variables (job assignment at time intervals to workers) (modeling). Since the model is a linear programming model, the Lingo optimization software and coding in it is used to solve optimally (model solving and verification).Results: The optimal model of job rotation system was evaluated in semi-industrial work-station where dissatisfaction of workers from ergonomics problems has been reported (model implementation). This mathematical linear model is constructed with 144 decision variables, 57 constraints and a objective function. The model is implemented by Lingo software and the results include 138 zero optimal variables and 6 one optimal variables. These results provide an optimal sequence of assignment and workers job rotation that can be used to make most moderate state of job risks and divide the job risks in a logical proportion among all workers. The optimal assignment of jobs to workers implies the reduction of job risks for all workers to 1.25 (calculated value for optimal objective function).Conclusion: The main output of this research is an optimal plan for job assignment in a work plan of a production system which not only considers job conditions but also minimizes ergonomic risk of jobs and also leads to job satisfaction due to moderate job risk. The results demonstrate outstanding effect of job rotation on setting of job risk among workers at an appropriate level, and improvement on workers' satisfaction.

Background and aims: Job burnout is the person's reaction to interpersonal stressors in the workplace. This research has been conducted to examine the role of occupational motivation and procrastination in predicting of job burnout the employees of Ahar city hospital.Methods: The research conducted with the correlational method on 126 staffs' of the hospital that selected by random sampling. The questionnaire of staffs' occupational motivation, procrastination and Maslach's job burnout used in order to collect the data. The collected data analysed by Pearson correlation and multiple regression.Results: There is a significant negative relation between occupational motivation and job burnout (p<0.05). Also, there is a significant positive relationship between procrastination and job burnout (p<0.05). The results of multiple regression analysis showed that the scores of occupational motivation and procrastination can predict the job burnout scores.Conclusion: Occupational motivation, procrastination and job burnout are the important and effective issues in every organization. Considering the close relation these features together in any planning for research and reform, it is necessary to be considered this relation.

Background and aims: Cardiorespiratory capacity determines performance and productivity of daily jobs. Shoe production workers have heavy workload and musculoskeletal disorders are prevalent among them. Investigation on the relationship between musculoskeletal disorders (MSDs) and job strain index (SI) and physical activity capability of shoe workers can help to reduce MSDs.Methods: This study was done on 235 shoe workers of Tehran Great Bazar. Cases of the study were categorized as having 5 roles of cutting, coating, preworking, gluing, and finishing (packaging, etc.). Nordic questionnaire was used to assess the rate of musculoskeletal disorders, and Tux worth & Shahnavaz step-test was used to find aerobic capacity, and the job strain index was used for ergonomic estimation. All data were analyzed using SPSS 20 software.Results: Between job strain and musculoskeletal disorders of end part of upper limbs (right side, left side), a significant relationship was found (p<0.05). No significant relationship between VO2max index scores of shoe workers and musculoskeletal disorders of shoulder, elbow, wrist, ankle, hip, spinal cord, and waist, and all organs in general (p>0.05).Conclusion: Musculoskeletal disorders of terminal part of upper organs (wrist, shoulder, and elbow) had strong correlation with job strain. Proper planning to reduce job strain and ergonomic training can reduce the risk of MSDs in terminal part of upper organs in shoe makers.

Background and aims: Nurses play a pivotal role in the health care system. Nurses experience high stress levels due to the nature of their job, neglect of understanding and coping with this stress will result irreparable effects. Accordingly, the present study was performed to Determine predictor variables of job stress among nurses special sections was done.Methods: This study was a descriptive correlational study that was conducted in 2014. The instrument used in this study included a demographic questionnaire, Expanded Nursing Stress Scale (ENSS). Environment of research included critical care unites of Gorgan universal’s hospitals. Sampling was carried in census sampling method.74 nurses participated in the study. After collecting data analyzed in SPSS 16 software. Using descriptive statistic and deductive statistic at significant level of p<0.05.Results: The mean (SD) age of the participants was 33.39±6.33 years. Most stressful condition was conflict with the supervisor (2.65±0.59). The results of multiple regression analysis showed that the variables gender (b=21.57, p=0.014) and working in dialysis unit (b=27.08, p£0.001) are good predictors for occupational stress.Conclusion: According to the high level of some stress dimensions such as conflict with supervisor among nurses, and also the relationship between job stress and factors such as work in dialysis ward and gender, it is necessary Nurse Managers apply some measures to prevent and reduce stress by improving the work environment and sufficient support of personnel.

Background and aims: Taxi drivers are a large group of professional drivers, who spend so much time in driving. Considering traffic collisions as one of the failures of Traffic Safety System in the country, modification of improper driving behaviors of this group can result in a significant decrease in accidents.Methods: This analytical-descriptive study was conducted on 245 taxi drivers in 2013. A questionnaire was used to collect data in two sections: demographic information and reasons for not using the automobile lighting system at night. The content validity of the questionnaire was confirmed by the experts and professors’ comments and its reliability was confirmed by Cronbach's coefficient alpha (0.72).Results: It was found that 26.9% of the drivers do not turn on their automobile lighting system over night. Most in main squares of the city (46.2%). Forgetfulness in turning car’s lights (14.28%) and depreciation on car lights (13.06%) were the major reasons. Moreover, a significant relationship was observed among variables like working in taxi driving as the main occupation (p=0.0001), lack of receiving warning from passengers (p=0.0001), the level of education (p=0.012) and lack of using automobile lighting system.Conclusion: Considering that forgetfulness was the main reason for not using the lighting system and the fact that most of the drivers had received no warning or fine from police for not using lights at night, it is essential to use appropriate training and exertion of regulations to create correct culture of traffic and improve driver performance.

Background and aims: Standardized self-report questionnaires, because of their low costs and the ease of the summarization and analysis of their results, are considered as the most important and widely used approach to identifying and assessing work-related stressors.Current study was carried out with the aim of reviewing the available questionnaires for work-related stressor factors.Methods: In this systematic review study, all the available work-related stress questionnaires in the time span from 1975 to 2016 were collected through running search in several authentic indexing and citation databases and then the collected questionnaire were examined.Results: Generally, according to the criteria considered, a total of 23 questionnaires met the inclusion criteria for the final stage of the study. All these questionnaires had been designed and developed in industrial countries. However, according to our literature review, the psychometric properties had only been studied for the Persian translations of the Job Content Questionnaire (JCQ), the Effort-Reward Imbalance (ERI) questionnaire, the Copenhagen Psychosocial Questionnaire (COPSOQ), the Health & Safety Executive Management Standards Indicator Tool (HSE-MS), the General Nordic Questionnaire (QPS-Nordic), and the NIOSH Generic Job Stress Questionnaire (GJSQNIOSH).Conclusion: With regard to the diversity of available questionnaires and their subscales, it is suggested that Iranian researchers and organizations, firstly identify the stressor factors related to their own specific jobs through running qualitative studies and then start to assess the occupational stressor factors related to their specific job environments through developing their own standardized questionnaires or employing the subscales of the available questionnaires covering their specific problems.

Background and aims: Low back pain is a prevalent musculoskeletal disorder associated with nursing profession. This study was conducted to compare the effects of Williams ‘Exercise and Walking on relief of non-traumatic low back pain in nurses.Methods: In this semi-experimental study with pretest-posttest design, 100 nurses with chronic and acute low back pain and working in Ayatollah Kashani and Hajar hospitals of Shahrekord were studied between March 2015 and June 2015. The patients were randomly assigned to two groups of 50 each. Group 1 were asked to perform Williams exercise once a day and group 2 was asked to walk for 20 min per day. The demographic characteristics, medical history, and (chronic and acute) pain severity were investigated before and after the interventions. The data were analyzed by SPSS 22.Results: In both groups, mean difference in pain severity was significant after the intervention (p=0.001). Walking caused the pain of the nurses with acute low back pain to relieve more notably than the pain of those with chronic low back pain, while regarding Williams exercise, the pain relief was more marked in the nurses with chronic low back pain.Conclusion: Walking is more effective on reluef of pain due to acute low back pain, and Williams exercise was more effective on relief of pain due to chronic low back pain.Combining these exercises and other approaches of complementary medicine may cause greater pain relief.

Background and aims: In accomplishing attention-consuming tasks, mental fatigue reduces productivity and increases error rate as the factors involved in work accidents. The present research goal was to study the effects of sleep quality and mental fatigue on attention and reaction time in the thermal comfort condition.Methods: This experimental research was conducted on 33 university students in thermal stress chambers. The participants were exposed to 500, 200, and 1500 lx lightings for 1.5 hours at the 22 temperature to take the continuous performance test (CPT) (which assessed attention) and the reaction time test (which measured their reaction time), and complete the Pittsburgh Sleep Quality Inventory (PSQI) and the mental fatigue checklist. The collected data was analyzed in SPSS 20 using the multiple linear regression analysis and Pearson’s correlation coefficient methods.Results: There was a significant relationship between levels of mental fatigue before and after exposure to 200 and 500lx lightings, and the highest level of mental fatigue was observed with the 200 and 500lx lightings (p˂0.05). The relationship of mental fatigue before exposure to the 200lx lighting with the error rate and reaction time was significant (p˂0.05). The relationship of mental fatigue after exposure to the 500lx lighting and the two-sound selective reaction time was significant (p˂0.05). The relationship of sleep quality was not significant in the CPT (continuous performance test) test (p˃0.05), but the relationship of sleep quality with the diagnostic reaction time (with the 200lx lighting) and the two-color selective reaction time (with the 500lx lighting) was significant (p˂0.05).Conclusion: Research findings revealed that error rate, reaction time, and the inability to think increased because of extreme mental fatigue, inadequate lighting, and low sleep quality. Hence, it is necessary to optimize the heat and lighting of the workplace environments for positions that require attention, concentration and reaction to stimuli based on the sleep quality and mental fatigue levels.

Background and aims: HSE performance assessment is one of the most important necessities for progress, development, and sustainability of organizations. Apparently, the previous HSE performance models have not considered all of the contributed criteria. On the other hand, foreign models cannot culturally be applied in describing HSE performance in Iranian organizations. Therefore, this study was conducted with the aim of developing a new model for assessing and ranking of organizations HSE performance.Methods: In this expanding practical study, firstly, previous existed HSE performance models were identified; afterwards, common and distinct criteria were extracted.Simultaneously, interviewing with experts was done and performance evaluating criteria were recognized. For each criterion, some sub criteria and for each sub criterion, some guidance points were extracted. Finally, the weights of criteria and sub criteria were detected by paired comparison and Fuzzy analytical hierarchical process.Results: HSE performance assessment model was made of 9 criteria including safety results, health results, environment results, processes, economical and sociocultural results, policy and strategy, leadership, partnerships and resources, and human resources weighted respectively with 19 subcriteria and 157 guidance points.Conclusion: Results criteria weighted more in comparison with enablers criteria (59% and 41%, respectively). Three criteria including processes, policy and strategy, and leadership weighted partly 70 percent of enablers weights. Safety results gained the greatest rank and 28 percent of the results weight.

Background and aims: A human health risk assessment is the process to estimate the nature and probability of adverse health effects in human who may be exposed to chemicals in contaminated workplaces, now or in the future. The objective of this study is to compare risk assessment of carcinogen hydrocarbons of Environmental Protection Agency (EPA) method and Human Resource of Malasia method.Methods: The chemical compounds were benzene, epiclorohydrine, trichloroethylene, styrene, ethyl benzene and 1, 3-butadiene, that were emitted in workplaces and have carcinogenity risk therefore were considered for risk calculation in this study.The analytical procedure was based on method number 1501 and 2549 of National Institute Occupational Safety and Health, (NIOSH 1501 and 2549). Samples were analysed with gas chromatography-Mass spectrometry (GC–MS). The EPA method and Humun resources of Malasia were compared for health risk assessment of workers that exposed to carcinogen compounds in petrochemical complex.Results: The lifetime cancer risk in EPA method was compared to results of Humun Resources of Malasia. The results of EPA method showed that carcinogen risk for benzene and trichloroethylene in all petrochemical complexes and epiclorohydrine and ethyl benzene in most of complex were more than values recommended by the World Health Organization (WHO) but the carcinogen risk for these compounds were probability risk according the Humun Resources of Malasia method.Conclusion: The EPA health risk assessment emphasize on decrease of compounds in ambient air as they have not any hazardous on humun health and environment and methods confirm by Word Health Organization. The results of Humun Resources of Malasia method had not compatibility with EPA method.

Background and aims: Crashes and the related human and financial losses have been turned to be one of the challenges of human societies in a way that road death statistics shows a high number of 219172 in Iran from 2005 to 2014.Methods: In this research, using global and valid Road Safety Development Index (RSDI) that illustrates general roads safety condition and consists of nine effective parameters, roads safety in Iran and 10 countries of southeast of Asia was analyzed from March 2010 to March 2011. Considering the charechtristics of the parameters, two scaling methods entitle "Simple Average Weighting" and "Subjective Weighting" were used.Results: Iran's scores were 48.35 and 45.29 for Simple Average Weighting and Subjective Weighting respectively and was in middle level of safety also it ranked as the fourth country among 11 studied ones in 2011. Although some parameters got better, comparing three last years, in many of them especially number of death, crashes and drivers' behavior conditions were unacceptable. The important point is that Subjective Weighting method acts more accurate than Simple Average method, respects to considering change of weights according to importance and their role comparing.Conclusion: The research findings illustrated that Iran has moved toward middle level of road safety from lower levels in last years. However, regards to ranking and scores resulted from indexes it is not in desirable conditions.

Background and aims: Musculoskeletal disorders and lack of mental health are two very important problems among employed people. The present study was conducted to compare the ROSA and RULA methods in risk assessment of catching to musculoskeletal disorders and to find the relationship with mental health on computer users.Methods: Present study was a descriptive - analytic cross-sectional study.71 employees were selected from Isfahan University of Medical Sciences. Data collection was carried out in five stages as follows: 1) demographical data investigation 2) Prevalence investigation of musculoskeletal disorders with Nordic questionnaire, assessment of ergonomic factors risk in among employees using 3) ROSA method 4) RULA method 5) Evaluation of mental health. The collected data were analyzed by SPSS 20 software.Results: Assessment of staff body posture during work with two methods of ROSA and RULA had a direct and significant relationship (R=0.808 and p<0.001). Also, the final score of ROSA had a direct and significant relationship (R=0.555 and p<0.001) with mental health of the staff.Conclusion: Given that two methods of ROSA and RULA have a direct and desirable correlation with each other, each of these two methods can be used interchangeably with great confidence. In addition, the increase risk of musculoskeletal disorders was associated with mental health reduction in the staff.

Background and aims: The limited economic resources and investment in university educational hospitals is an important issue. Therefore, the optimal allocation of existing funds and resources has a great impact on providing appropriate medical services and improving the efficiency of hospitals. This study aimed to evaluate the performance and efficiency of hospitals in Tehran University of Medical Sciences.Methods: In this study, by employing data envelopment analysis, the performance of 40 hospitals of Tehran University of Medical Sciences was evaluated through five inputs and eight outputs, by assuming variable return on scale and with an input-and-output-based approach. Finally, the ranking of efficient units was done by PROMETHEE method.Results: The results of DEA method showed that 13 out of 40 hospitals had a performance less than one and they were inefficient. Then, using PROMETHEE ranking method, Hospital 20, with a net flow of 0.7452, was designated as the best hospital among efficient hospitals.Conclusion: The sensitivity analysis on weights was shown that the results of the model were reliable and had high efficiency. Using the results of this approach, top managers of healthcare centers can apply necessary planning to optimally use their resources.

Background and aims: Agricultural activities for producing more products may compromise farmers’ health and cause environmental pollution. This study was carried out to assess the status and correlations between knowledge, attitude and practice of greenhouse farmers of Jiroft town in relation to adverse health and environmental effects of the use of pesticides in 2015.Methods: This cross-sectional study was performed on 196 greenhouse farmers of Jiroft town in 2015 with multistage random sampling method. Data were collected using a researcher-made questionnaire and analyzed by using Spearman correlation test, Mann-Whitney and Kruskal Wallis tests through SPSS v.18 software.Results: The average age of participants was 39.77±8.11 years and 96.4 percent were male.Average score of Knowledge was 20.54±1.85, Attitude 32.88±3.27 and performance was 35.21±2.41. The performance score was statistically positive correlation with Knowledge and Attitude (p<0.001). As well as the knowledge to gender, age, location, history of Farming and greenhouses (p<0.05), attitude with Farming history and greenhouse farming history has significant positive relationship (p<0.03).Conclusion: Unsatisfactory performance score of farmers in cases that can exert harmful effects to their health, greenhouse products and environment shows that necessarily the optimal knowledge and attitude will not be cause to optimal Performance and is needed for planned interventions based on health education and health promotion models that consider the intrapersonal and interpersonal and other factors are taken into consideration.