yahya rasoulzadeh

Numerous physical and chemical agents can induce destructive effects on the brain tissue. Noise and toluene, which are some of these harmful agents, have significant adverse effects on the brain tissue. This work aimed to investigate the neurotoxic changes induced by co-exposure to toluene and noise. 

A total of 24 male white New Zealand rabbits were randomly segregated into four groups, including toluene exposure, noise exposure, co-exposure to noise and toluene, and control. This in vivo study tested the neurotoxic effects of exposure to 1000 ppm toluene and 100 dB noise during two weeks (8 h/day). The serum levels of brain-derived neurotrophic factor-α (BDNF-α), malondialdehyde (MDA), glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase and total antioxidant capacity (TAC) values in the brain tissue were measured. Moreover, hematoxylin and eosin (H&E) staining was utilized for brain pathological analysis.

Exposure to noise increased TAC values in the cerebral cortex. Co-exposure to toluene and noise increased the serum levels of BDNF-α. Nevertheless, exposure to noise decreased the levels of BDNF-α in serum. On the other hand, histopathological examinations using H&E staining exhibited that different signs of inflammation, such as lymphocyte infiltration, pyknosis, vacuolization, and chromatolysis were induced by exposure to noise and toluene in the cerebellum, hippocampus, and frontal section in the brain tissue. In addition, simultaneous exposure to toluene and noise induced antagonistic and synergistic changes in some neurotoxic parameters.

Exposure to noise and toluene, which caused inflammation in the brain tissue cells, could be a noticeable risk factor for the neurological system.

The accurate evaluation of error probability and risk is important. Accordingly, this Comparative study was conducted to evaluate the risk of human error in emergency situations using SLIM and Fuzzy SLIM techniques in fierfighting tasks.

This cross-sectional and descriptive-analytical study was conducted among 12, using Fuzzy SLIM and SLIM techniques. 39 sub-tasks were studied in 4 phases (Awareness, Evaluation, Egress and Recovery). Considering the advantages of the Fuzzy SLIM method, fuzzy logic was used in weighting of performance shaping factors (PSF). Excel software was used to calculate the probability of error. Also, correlation and kappa statistical tests were used for data analysis in SPSS software.

The mean and standard deviation of human error probability in different sub-tasks of firefighting in SLIM and Fuzzy SLIM methods were 0.095357 ± 0.026193 and 0.06490 ± 0.051748, respectivly. In 48.7 percent of the sub-tasks, the probability category of human error and the assessed risk were the same; however, in 89.7 percent of the sub-tasks, the estimated level of risk was the same in both methods. Correlation test showed that the correlation coefficient of error probability values between the two methods was 0.32, which indicated a moderate correlation in this regard. Additionally, the results of kappa statistical test for the estimated level of risk showed that there is a high agreement between Fuzzy SLIM and SLIM (P value <0.05).

The results of the study indicated meaningful agreement and a moderate correlation between Fuzzy SLIM and SLIM. Therefore, due to the relatively high accuracy of Fuzzy logic methods, and also the long steps of implementing the SLIM method, the Fuzzy SLIM method can be a good alternative to this method.

Carbon-based nanomaterials (CBNs) are the key elements in nanotechnology. The main challenge presented by CBNs is their relationship with the toxicity exposed in the biological systems, because of the incomplete information on their toxicity. This study is aimed to compare the cytotoxicity of graphite nanoparticles (GRNPs), graphene nanoparticles (GNPs), and multi-walled carbon nanotubes (MWCNTs) in A549 cells.
The physicochemical properties of nanomaterials were determined by instrumental techniques. CBNs were dispersed by the nongenotoxic standard procedure. After the cells were cultured, they were exposed to different concentrations of CBNs. Cellular viability was determined by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) method. Moreover, toxicological indicators were obtained using linear probit regression.
The degree of cytotoxicity of CBNs in A549 cells was related to the time and, particularly, dose. At the concentrations of lower than 300 μg/mL, GNPs had stronger toxicity than MWCNTs, but the cytotoxic effects were reversed with the increase of the concentrations. The no-observed-adverse-effect concentration (NOAEC) of GRNPs, GNPs, and MWCNTs was 1.76, 0.06, and 0.65 μg/mL, respectively.
The results indicated that CBNs were toxic and GNPs had stronger toxicity than the others. The experimental results can be useful in increasing the knowledge about the toxicity and health risk management of CBNs.

 The International Agency for Research on Cancer (IARC) identified formaldehyde as a carcinogen in 2004, yet formaldehyde is widely used in health care settings and various industries. In recent years, photocatalytic oxidation has been developed as a potential technique for removing pollutants arising from organic chemical agents and consequently promoting the health indices. This study investigated the effect of operational factors in optimizing formaldehyde removal from the air using Ag3 PO4 /TiO2 photocatalyst.

 An experimental study was designed to investigate the effect of operational factors on the efficiency of formaldehyde degradation. The variables investigated in this study include pollutant retention time, initial pollutant concentration and relative humidity. Sol-gel method was used to synthesize the nano-composite photocatalyst. An ideal experimental design was carried out based on Box-Behnken design (BBD) with response surface methodology (RSM). The sample size in this study includes all the glasses coated with Ag3 PO4 /TiO2 photocatalyst.

 The maximum formaldehyde degradation of 32% was obtained at the initial concentration of 2 ppm, 20% relative humidity, and 90 minutes of retention time. Based on the statistical results, the correlation coefficient of the present study for the impact of operational factors on formaldehyde degradation was 0.9635, which means that there is only 3.65% probability of error in the model.

 The operational factors examined in this study (retention time, relative humidity, and initial formaldehyde concentration) were significantly influential in the degradation efficiency of formaldehyde by the photocatalyst. Due to the high exposure of employees and clients of health and treatment centers to formaldehyde as a carcinogenic substance, the results of this study can be used in ventilation systems to remove environmental pollutants in health care centers and other occupational settings.

Computer vision syndrome (CVS) is one of the most common health concerns associated with the extensive use of computers, particularly in the working environment. Since recent studies have shown the high prevalence of CVS, it is necessary to have an appropriate tool for assessing this prevalence. The present research aims to translate the CVS questionnaire and analyze its validity and reliability and assess the incidence of this condition among the staff members at Tabriz University of Medical Sciences.

The translation of the main questionnaire into the Persian version was carried out in three steps. Two coefficients including the content validity ratio (CVR) and the content validity index (CVI) were used to evaluate the content validity of the questionnaire. The reliability of the questionnaire was examined using two methods including internal consistency (Cronbach’s alpha) and test-retest. In total, 240 participants were asked to fulfill the questionnaire in order to investigate the prevalence rate of CVS among the staff members of Tabriz University of Medical Sciences. After removing the ineligible ones, 219 questionnaires were examined.

The internal consistency coefficient and Cronbach’s alpha coefficient were 0.91 and 0.89, respectively. Out of a total of 102 women and 117 men, only 19 women and 21 men did not have CVS. Among the studied symptoms, eye redness (78.1%), burning (76.7%), and headache (74%) were the most prevalent in the statistical population. No significant relationship was observed between the final score of CVS and gender.

In terms of validity and reliability, the questionnaire was found to be satisfactory. The prevalence of CVS among the staff members of Tabriz University of Medical Sciences was high (81%). To determine the etiologies, further research is needed.

Noise and toluene are among the numerous physical and chemical pollutants that can induce adverse effects on different body tissues and systems; nevertheless, most studies have only experimented the auditory changes induced by co-exposure to them. The present in-vivo study aimed to examine the endocrine effects of co-exposure to toluene and noise on the testes and adrenal glands. In this experimental study, 24 healthy male New Zealand White rabbits were used. The noise intensity was 100 dB (white noise) and the toluene concentration was 1000 ppm for two consecutive weeks. The luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, cortisol and adrenocorticotropic hormone (ACTH) were measured using the enzyme-linked immunosorbent assay (ELISA) method. The hematoxylin and eosin stain method (H&E) was performed for the histopathological analysis. Comparing different parameters in different groups on post-exposure days was carried out using GEE (generalized estimating equations) method. The results indicated that noise and toluene increased cortisol, LH and FSH levels during different days after the exposure. Exposure to toluene and noise made vacuolization and reduction of primary spermatogonial cells in the testes. Moreover, lymphocyte infiltration, congestion, swelling and vacuolization were detected in adrenal glands through exposure to toluene and noise. Toluene and noise induced different destructive effects on the endocrine system. More studies are required to elucidate other endocrine changes induced by exposure to toluene and noise.

Rapid population growth and industrialization have increased chemical pollutants. Some studies show that employee exposure to formaldehyde in industrial places, hospitals, and laboratory settings is more than the allowed limits. Therefore, it is necessary to implement a proper control system to reduce this exposure. This study aimed to synthesize Ag3PO4/TiO2 nanocomposite, determine its morphological and structural characteristics, and test the degradation efficiency of this photocatalyst on formaldehyde.

Ag3PO4/TiO2 composites were synthesized via an in-situ precipitation method. The physicochemical, morphological, and optical properties of the synthesized sample were investigated by employing the BET method, X-ray diffraction (XRD), UV–visible absorption spectroscopy, and scanning electron microscopy (SEM). The photocatalyst degradation efficiency test was performed on gaseous formaldehyde in a 3.2-liter photoreactor under visible light radiation.

The UV–Vis absorption spectrum of the Ag3PO4/TiO2 sample noticeably shifted to the visible light region compared to that of the TiO2. The bandgap energy of the nanocomposite was 2.3 eV. The SEM image demonstrated that the average particle size of the nanocomposite was about 102 nm. The result of the degradation efficiency tests revealed that 63% of the formaldehyde was removed under visible light irradiation after 90 minutes by the Ag3PO4/TiO2 photocatalyst.

The adopted synthesis method adopted was highly efficient and appropriate for the synthesis of Ag3PO4/TiO2 nanocomposite according to the analyses. The Ag3PO4/TiO2 photocatalyst performed well under visible light radiation and could be used in pollution control systems.

Electrospun nanomembranes have been used for effective air filtration due to their potential for active surface modification. This study aims to synthesize polyurethane (PU) nanofiber membrane incorporated with different amounts of β-cyclodextrin (β-CD) to capture volatile organic compounds (VOCs) along with aerosol filtration from the air.

First, PU was synthesized by MDI method. A 10 wt% PU solution in DMF/MEK (1:1 wt) was prepared. Various amounts of β-CD powder (0, 1, 2, 3, and 5 wt% of PU) were dispersed in the prepared PU solution. Electrospining process was carried out under determined parameters (20 kV applied voltage, tip-to-collector distance of 10 cm, solution feed, and rate of 1 ml/h). The chemical structure and morphology of the produced samples were assessed by FTIR and SEM, respectively. Finally, air filtration and toluene adsorption of different electrospun membranes were measured.

The highest filtration performance was observed for PU with 1 wt% β-CD nanofiber. Due to increased efficiency (83.13%) and low-pressure drop (∆P = 19 pa), this sample had a considerable quality parameter. The results demonstrated that the membrane loaded with β-CD was able to adsorb hazardous and carcinogenic VOCs. It was confirmed that adding β-CD into PU improves the adsorption capacity due to forming a π complex and having a different tendency against capturing a variety of VOCs.

The study results revealed that the PU nanofiber incorporated with β-CD, along with the ease of regeneration, can make them attractive for air filtration and VOCs adsorption.

Noise exposure is a common phenomenon in all personal life activities. Due to the prevalence of exposure to noise, many people are exposed to noise. Some of the harmful effects of noise on human health
have been proven so far. The purpose of this study was to experiment histopathological effects caused by exposure to white noise.

Four New Zealand white rabbits were exposed to 85±2 dB white noise for five consequent days. Heart, kidney, liver, and lung tissues were studied by the Hematoxylin and Eosin staining (H&E) method. The independent t-test was used for comparing the mean weight of tissues.

This study showed that exposure to 85±2 dB white noise did not significantly change heart and lungs tissues. Nevertheless, this study indicated that exposure to noise induced different pathological changes  in kidney and liver tissues. Exposure to noise made congestion, unclear brush border, and tubular cell vacuolization in kidney tissue. Moreover, eosinophilic cytoplasm was made by noise exposure in liver tissue. Furthermore, no statistically significant difference was detected in the mean tissue weight/mean body weight in rabbits.

This study showed that exposure to noise might be a risk factor for different renal and hepatic diseases. Nevertheless, more studies need to complete these results.

Ergonomic risk factors are one of the main factors in the occurrence of Work-related Musculoskeletal Disorders (WMSDs). The serviceman workers are exposed to various health and safety risk factors during their activities. This study aimed to assess the risk of musculoskeletal disorders in serviceman workers of a Petrochemical company.

Method and Instruments:

 In this descriptive cross sectional study, first, the posture of 106 serviceman workers were assessed using REBA method. Then, the prevalence of WMSDs symptom was investigated using Nordic Questionnaire (NQ). The collected data were analyzed by SPSS software using statistical Chi-square test.

Rapid Entire Body Assessment (REBA) score for serviceman workers involved in insulation, electrical and Instrumentation related work was 11, 12 and 13 (high risk) respectively. The highest prevalence of musculoskeletal disorders was reported in the lower back and knees. Significant relationship (p <0. 05) was observed between work experience and disorders symptom in knee.

This study showed high prevalence of WMSDs symptom in study population, especially in their waist and knee. Moreover, it was indicated that the working conditions of serviceman workers needs to be improved. Training the workers to identify the risk factors and use proper ergonomic principles and procedures is recommended.

Nowadays, multi-walled carbon nanotubes (MWCNTs) are used in various industries. Considering the exposure probability of these nanomaterials to humans, the purpose of the present study is to assess the effect of MWCNTs on cellular toxicity of human alveolar epithelial. The A549 cells were cultured and treated to various doses of MWCNTs at three different times. Finally, the Tetrazolium colorimetric (MTT) assay was implemented for evaluating the cellular viability. The results indicated that the cytotoxicity for MWCNTs on the human alveolar epithelial cells is related to dose and time of exposure. The inhibitory concentration of 50% (IC50) and non-observed adverse effect concentration (NOAEC) are calculated to be 103.6 as well as 0.65μg/mL, respectively. The findings of this present study could contribute to a better understanding of MWCNTs substances and might be useful as a basis for the future risk evaluation studies of exposed population in industries.

Organizations are defined as a group with a specific structure and play an important role in the social, economic, and ecological systems. Disasters, accidents, and crises are complex and controversial issues for industries and organizations. Accidents and occupational injuries cause severe and significant economic losses in developing countries and result in the loss of millions of working days per year. With increasing disaster statistics in world, the ability to survive and thrive in turbulent times, such as recessions, disasters, crises, and wars, is a major concern for organizations and industries over the recent decade. Organizations must manage crises such as recessions, large-scale defective production, supply chain failures, major industrial accidents, and employee problems. The system should be designed in such a way which based on the results of past organizational disasters use a method to prevent and minimize accidents and their losses. Resilience in these types of events and crises is often less pronounced and manifested through an organizational culture. Organizational resilience is an effective objective that constantly contributes to the organizationchr('39')s performance during business, disasters and critical situations. In other words, resilience enables organizations to manage complex challenges in the organization. To create resilience, organizations need to be consistent and highly reliable. Resilience is defined as the ability of a system to recover after an emergency. According to the resilience model presented, thirteen dimensions of organizational resilience include leadership, employee engagement, situational awareness, decision making, innovation and creativity, effective participation, knowledge utilization, organizational island failure, internal resources, goal unity, inactivity status, planning strategies and stress testing programs. Considering the importance of organizational factors and the criticality of large industries, appropriate and important dimensions and areas for measuring corporate resilience should be identified. Then, by weighing and prioritizing the identified dimensions, useful information should be provided to managers and decision makers of organizations. Managers will use this information in planning to reduce risk and increase safety and resilience of organizations. In previous studies, 13 dimensions of organizational resilience were not combined and their weighting was not performed. Therefore, this study aimed to weight and prioritizes the 13 dimensions of organizational resilience in the face of major crises and major events in large industries.

The present study is a descriptive-analytical-applied study conducted in large industries (in three major industries including: a heavy machinery manufacturing company, a car parts manufacturing and assembly company, and a petroleum industry) is done. In the first step, the concept of organizational resilience and its dimensions were examined through a review of previous studies and opinion of the relevant experts in the subject. An extensive study was conducted to examine the literature. Therefore, the literature on organizational resilience including theses, conferences, and papers published between 2000 and 2019 was reviewed. After the initial screening, which included reviewing titles and eliminating duplicate and unrelated cases, a determined number of articles, abstracts and dissertations were reviewed. Accordingly, many article full texts were prepared to evaluate the dimensions, the methods and tools of the studies, the gaps and weaknesses of the studies, as well as the identified indicators and factors affecting resilience. After reviewing the literature and indicators extracted by the research team, 13 important and relevant resilience indicators were selected to design the tool, namely: management commitment, just culture, learning culture, knowledge of status, preparedness, use of knowledge and experience, communication and teamwork, creativity and innovation, leadership and decision making, planning and targeting strategy, effective participation, resources and responsibility.In the second step of the present study, the panel of experts was selected. Members of the panel of experts were selected based on cognitive criteria and scientific qualifications from experts in crisis management, occupational health and ergonomics. The final list consisted of 11 specialists (persons with relevant Ph.D. degree and one year of relevant work experience) in this field.In the third step of the study, the identified dimensions and domains for measuring the level of organizational resilience were provided to experts in the form of a paired comparative questionnaire (AHP questionnaire). They then presented their comments on pairwise comparisons between dimensions and between items of each organizational resilience questionnaire. It should be noted that for the representation of the pairwise comparisons matrix, a 9-Saati scale was used to determine the relative importance of each dimension in relation to others. After collecting the questionnaires, weighting of dimensions and organizational resilience scales were performed using AHP method and Super Decisions software.

The highest value of normal weight among dimensions of organizational resilience was related to leadership and decision making (0. 20583) and the least was related to resources (0.01246). In other words, the first and thirteenth priority among the 13 organizational resilience dimensions in this study are related to leadership and decision making dimensions and resources, respectively. It is worth mentioning that the areas of  knowledge and experience utilization and management commitment along with the leadership and decision making dimension have the relatively high weight (weight difference over the other ten areas of the questionnaire) and the dimensions of preparedness and responsibility and resources have relatively less weight. It is also worth noting that the inconsistency rate (0.0138) was less than or equal to 0.1 which is indicating the validity of the pairwise comparisons and thus the results of the weights can be trusted. Also, considering the results related to weighting the items related to each of the dimensions of the organizational resilience questionnaire (to show the importance of the items specific to each domain of the organizational resilience questionnaire, it can be stated that all the obtained incompatibility rates were less than or equal to 0.1. As a result, it can be said that the pairwise comparisons are correct and that the weights assigned to all the items can be trusted. 

Given the importance of organizational resilience and the criticality of the industries under study, appropriate dimensions and indicators should be identified to measure organizational resilience. Then by providing weighting and prioritizing indicators and areas of organizational resilience, useful information is provided to managers and decision makers and it can be used in planning to reduce risk and increase the level of safety and resilience of the organization. In other words, critical industries and organizations (characterized by high complexity and vulnerability and susceptible to major disasters) can focus on priority-influenced indicators to improve safety and resilience management. Modifying and improving effective performance indicators will improve the safety and resilience of the organization. According to the findings of the research, leadership and decision-making dimensions, the use of knowledge and experience and the management commitment are more effective than other components in organizational resilience. Therefore, it is necessary to make arrangements for organizations to become more familiar with the issues and benefits of safety and resilience and to rely on the support and commitment of managers as well as the knowledge and experience of employees to make the right decisions. These dimensions must be taken into consideration when developing measures to improve organizational resilience.The behaviors of managers in any organization, which should take the lead and make decisions, influence the thoughts, feelings, and desires of their supervised employees, which motivate and guide their behavior. Therefore, leadership and decision-making style as a facilitator and motivator have a direct and indirect impact on the efficiency of organizations as well as on the creation of organizational culture and safety culture. The results also showed that the dimensions of knowledge utilization, experience and management commitment were more relative to leadership and decision making. This important finding highlights the importance of these two dimensions in helping to promote organizational culture and thereby enhancing the level of organizational resilience.The results also indicated that among the 13 dimensions of organizational resilience, resource dimension is the top priority in terms of importance and weight gained. Whereas from the expert panelchr('39')s perspective, the concept of resources refers more to the financial resources and equipment in the organization and the impact of human resources (managers and employees) is more represented in other areas of organizational resilience. Therefore, with this perspective, the levels of personal, safety and organization culture due to the lack of staff involvement in resources is reduced.

In recent decades, the essence of work was changed because of the great evolutions in several parts of manufacturing and industry. Increasing global competitive marketing was a cause of these changes. Generally, changes in work include: mechanization, automation, information technology, organizational restructuring, work-related modification and staff multitasking. According to these changes, the need to learn and develop new skills led to increased psychosocial factors including job stressors. Almost, the majority of people experience job stressors at work. Job stress occurs when there is no balance between job demands and worker’s capabilities. In several studies, job stress is identified as an important and effective factor that effects on health, performance and industrial safety. Usually, workers exposed to several stressors in the workplace, including: relationships and tensions among employees, high workload, long work hours, poor job design, role ambiguity or conflict, weak support from management and coworkers, high-speed work and so on. Job demands like workload, physical factors of the workplace and job control manner are the most effective stressors on the workerschr('39') life. Fatigue is a significant negative consequence of these stressors. For example, high job demands lead to impaired cognitive functioning and tired feeling that those are the fatigue symptoms. As regards the fewer studies about stress among industrial workers in Iran and there is no study on the relationship between job stressors and fatigue among Iranian workers, this survey was performed to study relationships among job stressors, especially job demands and job control, with fatigue; also, assessing the fatigue changes during the working day according to the job stressors was the other aim of this study.

This survey was a cross-sectional study that gathered from three hundred and thirty-eight industrial workers from the big industries of Tabriz city. The purpose of the study was explained with clarity to all participants. Only those who agreed to participate in the study and who had more than one-year working experience, healthy people (Who didn’t suffer from diabetes, asthma, blood pressure and anemia) and those who worked in day shift, were enrolled. Participants were selected by a convenient method for this study. A valid job stress HSE questionnaire, a demographic factors questionnaire and fatigue checklist were used to conduct data. At first, to study and evaluate of fatigue in time, a designed checklist was used. According to the aim of this study, we designed a checklist that measures worker’s acute fatigue in every time of working day. By this checklist, the participants rated their fatigue in the range of 0-10 (0= there is no fatigue feeling, 10=there is an excessive fatigue feeling), at specified hours during the working day from 7:00 to 18:00. Then, the demographic questionnaire and fourteen items of job stress questionnaire to evaluate job demands and job control were provided to participants. The scoring of job stress questionnaire was ranked from 0 to 4 (no to more) in this study. To data analyses, the working day was divided into three times, time 1 was from 7:00 to 10:00 (7:00, 8:00, 9:00 and 10:00), time 2 was from 11:00 to 14:00 (11:00, 12:00, 13:00 and 14:00) and time 3 was from 15:00 to 18:00 (15:00, 16:00, 17:00 and 18:00). Then, the average of fatigue was computed for each time. The variables of job demands and job control were adjusted between two groups (little and more) at the start of the study. The normality of quantitative data was evaluated by K-S test, identity of the covariance matrix was checked by Mauchlychr('39')s W test and the Nested Repeated Measure and Controlling Covariates test was used to investigate fatigue among three time periods by SPSS Software Version 25. At the end, the Controlling Covariate test was used by Minitab Software Version 18.1 to control of confounding variables. The results include three P-values for comparing groups between three times. The first was P-value (Group) for comparing between three groups, the second was P-value (Time) for comparing between three times (time 1, time 2, and time 3), and the third P-value (Level) was computed for comparing fatigue in each depression levels. The level of significance was set at P-value < 0.05. All results were expressed as Mean ± SEM (standard error of the mean).

According to the results, the mean age of workers was 37.04±0.4 years; and the mean working experience of workers was 11.45 ± 0.35 years. Also, the majority of the participants were male workers. About 52 percent of workers had more than 11 years of work experience and 62 percent of participants were fixed shift workers. The workers worked on average 203.65±1.8 hours in month. They had a mean 30.57±1.4 minutes rest-time in a day. Fifty and three percent of workers believed that they had a moderate income while the others were dissatisfied with their income, and they considered it inadequate. Results showed that job demands variable was significantly related to fatigue in time (p<0.001) and fatigue was increased by increasing of job demands (p<0.001). According to the results, by increasing job demands level from low to high, the severity of fatigue has increased. Also, the significant relationship between job control and fatigue was showed in results (p<0.001). According to the results, by decreasing job control level from high to low, the severity of fatigue has increased (p<0.001). At the end, the mean of fatigue had a positive trend from the start of working day and was increased by spending of time; fatigue score was increased by changing time from time 1 to time 2 and from time 1 to time 3 (p<0.001).  

The job stressors, especially job demands and job control, have adverse effects on several aspects of human life; fatigue is one of these negative consequences. According to the results, fatigue is a gradual process that increases by spending time from the starting of job activities. If so, the level of job control is low, or the job demands are higher than the capacity of workers in an organization, the severity of fatigue will increase. The importance of these findings is in the planning and implementation of necessary actions to reduce fatigue and its related incidents. So, it is recommended that industry managers and relevant authorities take proceedings to reduce the effects and severity of fatigue by reducing the time pressure, work speed, and workload and increasing the power of decision-making and application of work skills. Organizations also can reduce fatigue by decreasing the long hours of work and dedicating enough time for the rest of the workers.

Fatigue is one of the most important issues relating with safety and other aspects of human life. To understand fatigue and its relative factors and causes, there is a need to useful instruments, such as self-reported scales. The purpose of this study is to identify and present useful self-reported scales to measure fatigue.

Data were extracted from following three databases, ISI Web of Science, Scopus and Science direct and the search was undertaken for the period of 1996-2018. The search scope of this study was in ergonomics and health outcomes and the language of elected scales was in English. The articles that used objective fatigue scales or used the subjective scales for sleep-related studies were excluded from the review. Screening and appraisal of 12540 articles resulted in 115 articles being included in this review.

According to the obtained results, details of 12 self-reported fatigue scales are reported. These scales are divided in two types; five scales of them are in unidimensional scale group and the others are multidimensional scales. The Brief Fatigue Inventory (BFI) scale is the shortest form of scales in this study. Although, the Multidimensional Fatigue Symptom Inventory (MFSI) and Swedish Occupational Fatigue Inventory (SOFI) scales by more items can evaluate five aspects of fatigue. Six questionnaires of these scales were measured fatigue among working people.

There are several scales with acceptable validation to distinguish and measuring fatigue in studies or at work.

In recent years, the foundry industry has had a significant impact on Iran's economy. However, the health and safety conditions of this industry are in an unfavorable status, and these conditions have caused a lot of accidents. In this regards, one of the most important ways to prevent accidents in this industry can be identifying hazardous points and adopting appropriate control measures. The aim of the study was to identify hazardous points in foundry industry using a hybrid safety approach. This descriptive-analytic study was conducted in the foundry industry of Iran, in 2016. The study method consisted of two parts. First, the accidents of foundry were analyzed. Second, the Energy Trace and Barrier Analysis (ETBA) technique was used to identify hazards and assess the risks. The collected and obtained data of accidents and risk assessment were entered into the statistical SPSS software, version 22, and descriptive statistics (mean, percent) were used for analyzing. Also, Microsoft Excel was used to plot the graphs. A total of 128 risks is identified, including 17 unacceptable risks, 93 undesirable risks, 13 acceptable risks with revision and five acceptable risks without revision. The mechanical and physical energies had the highest percentage of hazards. The results of accidents analysis showed that the cause of most accidents (40%) was mechanical, while 23% of them was the potential type. The study results indicated that accidents analysis along with risks identification can be useful in identifying all the dangerous locations (points). In addition to validating the results of risk assessment through the analysis of accidents, other causes affecting the occurrence of accidents can also be covered by accident analysis, including unsafe behaviors and organizational causes that are not seen in the risk assessment.

In recent years, the foundry industry has had a significant impact on Iran's economy. However, the health and safety conditions of this industry are in an unfavorable status, and these conditions have caused a lot of accidents. In this regards, one of the most important ways to prevent accidents in this industry can be identifying hazardous points and adopting appropriate control measures. The aim of the study was to identify hazardous points in foundry industry using a hybrid safety approach. This descriptive-analytic study was conducted in the foundry industry of Iran, in 2016. The study method consisted of two parts. First, the accidents of foundry were analyzed. Second, the Energy Trace and Barrier Analysis (ETBA) technique was used to identify hazards and assess the risks. The collected and obtained data of accidents and risk assessment were entered into the statistical SPSS software, version 22, and descriptive statistics (mean, percent) were used for analyzing. Also, Microsoft Excel was used to plot the graphs. A total of 128 risks is identified, including 17 unacceptable risks, 93 undesirable risks, 13 acceptable risks with revision and five acceptable risks without revision. The mechanical and physical energies had the highest percentage of hazards. The results of accidents analysis showed that the cause of most accidents (40%) was mechanical, while 23% of them was the potential type. The study results indicated that accidents analysis along with risks identification can be useful in identifying all the dangerous locations (points). In addition to validating the results of risk assessment through the analysis of accidents, other causes affecting the occurrence of accidents can also be covered by accident analysis, including unsafe behaviors and organizational causes that are not seen in the risk assessment.

Disasters, incidents and crises are complex and controversial issues for the industries and organizations. Organizational resilience is an effective goal that continuously helps the organization’s performance throughout business, disasters and critical situations. Therefore, the present study aimed to investigate the validity and reliability of organizational resilience questionnaire in dealing with major accidents.
Material and

The present study was a descriptive-analytic study. At first, the concept of organizational resilience and its dimensions were determined for the review. Then, for evaluating the content validity, the designed questionnaire was distributed among members of the expert’s panel and the Content Validity Index (CVI) and Content Validity Ratio (CVR) were calculated based on the comments. The reliability of the questionnaire was determined after completing it by 272 employees of the studied industries.

The CVR was higher than the standard value (0.50) considering all items. Also, all dimensions of the questionnaire, except for the responsibility dimension the CVI’s were above 90%. Cronbach’s alpha coefficient for all questionnaire dimensions except for the responsibility dimension was higher than the acceptable value (0.70). This coefficient for the whole questionnaire was 0.967 indicating that this index was in excellent level.

The findings showed that the organizational resilience questionnaire in dealing with major accidents had an acceptable validity and reliability and in order to examine the organizational resilience in organizations, it could be used as a comprehensive, strong and reliable tool

Occupational accidents and review them in the field of industrial safety are the most important issues. If these accidents are investigated and analyzed, there will be the possibility of reducing their occurrence. This review aims to provide valuable information for researchers and reviewers of occupational accident.
In this study Persian-language academic journals were studied systematically. The aim was finding, classifying and analyzing the articles were published in these journals since the beginning of 1380 until the end of 1393 on occupational accidents. At the first list of scientific journals (59 journals) and then, the articles related to occupational accidents (Article 106) were selected. A criterion for the selection of the journals was existence at least one article in the field of occupational accidents published in them. Articles were analyzed according to publication year, journal and field survey.
The results showed that most studies were about healthcare (19.80%), manufacturing (16.98%) and epidemiology (11.32%) respectively. Also in the first six years of study, only 12 articles (11.32%) have published in the field of occupational accidents while in the six years at the end of study, 73 articles (68.86%) were published. 42 journals published only one article and 17 journals published more than one article in the field of occupational accidents. The Journal of Occupational Medicine and Iran Occupational Health were assigned of 19.80% of the articles.
This study can be used as a scientific resource for researchers and specialists in occupational health and safety field and help to Improving researches in the field of occupational accidents in Iran.

Individual factors are usually important as non-occupational parameters that participate in the prevalence of musculoskeletal disorders. Personality traits are one of the individual factors that affect physical illness, which are constant over time, thereby reflecting stable individual differences. Identifying the personality trait can be used to predict musculoskeletal disorders in workers and select individual with appropriate personality traits for different works..
The purpose of the present study was to identify the personality traits used to determine the relationship between different personality traits and the prevalence of musculoskeletal disorders..
136 people of 2 different companies in Tabriz (in 2015) were selected as the study population. The first group was selected from the petrochemical repair workers and the second from a dairy factory. The 50-item version of Goldberg’s big five personality scale was used to assess the personality traits. Nordic questionnaire was employed to evaluate the prevalence of musculoskeletal disorders. Chi-square test was incorporated for analyzing the data. Finally, logistic regression test was used to study the factors affecting upper and lower body pain..
Results indicated that individual personality traits were associated with musculoskeletal disorder prevalence in some members of body: Extraversion with wrist (P-value = 0.013) and hip (P-value = 0.044), emotional stability with shoulder (P-value = 0.012), wrist (P-value = 0.043), back (P-value = 0.034), low back (P-value = 0.029) and ankle( P-value = 0.014), Conscientiousness with Hip ( P-value = 0.009), Agreeableness with shoulder (P-value = 0.004), back (P-value = 0.001), Hip ( P-value = 0.006) and ankle ( P-value = 0.019)..
According to the results of this study, the personality traits can contribute to musculoskeletal disorders. Therefore, notice of personality traits can be used to predict individuals who are prone to musculoskeletal disorders. Necessary actions may be tailored for the people that are proportional to individual personality traits to prevent musculoskeletal disorders. As a further study, it is recommended that a better relationship may be revealed between personality traits and musculoskeletal disorders..

Backgrounds and Exposing with bioaerosols can be resulted in widespread adverse health effects including infectious and epidemic diseases, acute toxicities, allergies and even cancer. From this point of view, bioaerosol contaminations in hospitals can cause various secondary health problems. This study was conducted to survey the quality and quantity of bioaerosols in various hospital wards in winter.
In this cross-sectional descriptive study, the air samples were collected and analyzed according to NIOSH-0800 standard method. Air samples were taken through single-stage impactor using a high volume sampler at 28.3 ±0.2 l/min flow rate during 10 minutes. Sabouraud dextrose agar and blood agar plates were used as sampling media within impactor for fungi and bacteria, respectively.
The obtained results showed that, in average, the infants ward in Fatemeh hospital and general clinic in Abbasi hospital had the most bacterial contamination load. In contrast, the operating rooms in Fatemeh hospital and radiology ward in Abbasi hospital had the lowest bacterial contamination load. The independent T-test showed that the bioaerosol contamination in Abbasi hospital was significantly higher than Fatemeh hospital. Also, the most detected fungi were Aspergillus, Penicillium and Cladosporium.
This study indicated that the bioaerosol concentration in most wards of both hospitals exceeded the standard permissible limit (30 CFU/m3). Preventive control measures should be designated and implemented to decrease the exposure rate of patients and clients.

Shift work is a well-recognized occupational health hazard in both industrialized and industrially developing countries. Prolonged working time, day/night shift rotation, circadian rhythm and sleep disorders, family and social problems are the most important features of shift working, which have serious complications. The present study evaluated the fatigue and psychological distress and their relationship among shift workers, in a petrochemical plant (Southern Pars gas field) in Southwest Iran.. In this cross-sectional field study, 400 shift workers from a plant were involved, with participation rate of 72.5% (290 persons). The multidimensional fatigue inventory (MFI-20) and general health questionnaire (GHQ-28) were used to evaluate the level of fatigue and psychological distress, respectively.. The results showed that the fatigue and psychological distress (particularly social dysfunction, anxiety and insomnia) are frequent among 12-hour shift workers (the total MFI and total GHQ scores were 42.68 ± 17.88 and 34.66 ± 18.56). A relatively strong positive correlation was found between fatigue and psychological distress (r = 0.62). The results of the stepwise regression model indicated that the psychological distress was significantly related only to general fatigue, mental fatigue and reduced motivation, whereas it was not to the physical fatigue and reduced activity.. The study findings highlight the importance of the mental aspect of fatigue in this working group. These results have possible implications for workers’ health and well-being and for the design of shift work systems, for industrial workers..

Shift workers may be exposed to fatigue and mental disorders due to various work-related risk factors. This study evaluated the impact of demographic characteristics on fatigue and mental disorders among 12-hour shift workers in petrochemical industries. This study was conducted among 290 shift workers of Pardis Petrochemical Company in Iran. Data were collected using a general questionnaire for the demographic characteristic as well as multidimensional fatigue inventory (MFI-20) and general health questionnaire (GHQ-28). Married workers were less likely to suffer from reduced activity levels (P< 0.027), depression (P< 0.032) and mental disorders (P< 0.040). Social dysfunction score (P< 0.029) and mental disorders (P< 0.048) decreased with shift work experience. Shift workers with non-academic education less likely to suffer from reduced activity levels (P< 0.000) and mental fatigue (P< 0.028). Despite the significant difference between the variables, this study showed a weak effect of individual and occupational demographic characteristics on fatigue and mental disorders.

Asbestos fibers are used extensively in various industries including brake and clutch linings and airborne asbestos emission in urban environments can induce serious effects on human health، including pulmonary fibrosis and mesothelioma. The aim of this study was to access asbestos fibers emission in high traffic area of Tabriz city.

In this study، that was down 2012 (between ……. a ……) the concentration of asbestos fibers was measured at 12 high traffic areas of Tabriz city. The air samples were collected on membrane filters using integrated environmental sampling method for identification of asbestos fibers phase-contrast optical microscope was used to count the fibers with a length to width ratio greater than three.

The average concentration of asbestos fibers in high traffic areas (0/001 ± 0/0003 fiber /ml of air) was far more than the standard limits (0/00005 fiber/ ml of air). Also، the results of this study showed that the highest concentration of asbestos fibers was found in downtown area of Baghshmal square (0/0004 ± 0/0012 fiber/ml of air) and the lowest concentration was found in Shariati square (0/00056 ± 0/00012 fiber/ml of air).

This study showed that emissions of asbestos fibers from urban sources like such as vehicle brakes is so high that could create، increased respiratory complications and obligates us for more preventive measures.

According to the findings of several studies conducted on work-related musculoskeletal disorders (WMSDs) among the video display terminals (VDTs) users, Prevention of these disorders among this population is a challenge for many workplaces today. Ergonomically Improving of VDT workstations may be an effective and applicable way to decrease the risk of WMSDs. This study evaluated the effect of an ergonomics-training program on the risk of WMSDs among VDT users. This study was conducted among a large group of computer users in SAPCO industrialcompany, Tehran, Iran (84 persons with 29.85±11.2 years of age and with 6.98±2.54 years of experience). An active ergonomics-training program was designed and implemented during 14 days to empower the VDT users and involve them in improving their workstations. The direct observational RULA (Rapid Upper Limb Assessment) method was used in pre and postintervention stages to evaluate the risk of WMSDs among participants. The RULA final scores showed that 18.8 % of VDT users were at action level 2, 63.5% at action level 3 and 17.6% at action level 4 before any intervention. In addition, 8.2% of users were at action level 1, 44.7% at action level 2, 42.4% at action level 3 and 4.7% at action level 4 at the post-intervention stage. The results of Wilcoxon statistical test indicated that RULA scores ere decreased significantly after interventions (P < 0.05) and consequently, decreased risk of WMSDs. Active ergonomics training programs can be used effectively to improve the VDT workstations and decrease the risk of musculoskeletal disorders among VDT users.

Post-consumer waste polymers are considered as environmental pollutants thatshould be reused as inexpensive materials. Also, there are resources of naturalbitumen in several regions of Iran that can be used to modify bitumen. Thepurpose of this study is to investigate the possibility of obtaining penetration grademodified bitumen from vacuum bottom residue (VB) by adding various recycled wastepolymers and non-polymer materials without air blowing VB. Following this concept,natural bitumen (NB), recycled waste polyethylene (PE), recycled waste latex, crumprubber modifier (CRM) and heavy vacuum slopes (HVS) were used. The formulation ofmixing blends was determined by experimental design method using design-expertV.7.16 software. It was found that 40/50, 60/70 and 85/100 grades of penetrationbitumen with improved performance grades, 82-40, 70-40 and 70-40, respectively, areproducible using these materials, although, decreased ductility is observed almost forall the blends. A combination of 10% natural bitumen and 5% recycled latex with VB areconsidered as the best blend amongst all blends. The resulting modified 60/70 gradebitumen shows improved complex modulus in comparison with neat 60/70 bitumen andconsequently it has increased resistance against permanent deformation (rutting). Also,the lowered Frass breaking point of this blend (-21°C) improved its low temperatureperformance (PG = 70-40). Unfortunately, when the crump rubber modifier particles arenot well-dispersed and fine enough in bitumen matrix, there is an unexpecteddecreased ductility occurred in the blends.