Showing 116 results for Di
Mahboobeh Kefayati, Mahnaz Mirza Ebrahim Tehrani, Omid Saber Fard,
Volume 10, Issue 4 (11-2020)
Abstract
Introduction: Even with the rising number of diseases and their severity as well as occupational-environmental accidents occurring within organizations, most managers do not still care about the profitability of implementing the health, safety, and environment (HSE) management system requirements.
Material and Methods: Accordingly, the integration of the HSE costs calculated through engineering-economics relations was investigated to evaluate the given profitability using a different approach. For this purpose, costs of diseases and occupational-environmental accidents were computed (n=2207), and then lack of their spending was considered as system income. By determining the correlation and calculating the P-value as well as the associated costs, the regression model was subsequently fitted. Investment in the HSE management system was further examined, and return on investment (ROI) and net present value (NPV) were calculated. Afterwards, the relationship between ROI and disease recurrence rates together with occupational-environmental accidents was explored.
Results: health costs with a P-value=0.03 had a significant effect on disease recurrence rates, so that the incidence rate was equal to 1.432 e-15 as it increased by one unit. The costs of accidents with a P-value=0.048 also had a substantial impact on the occurrence of occupational accidents and a growth by one unit, wherein the accident recurrence rates were 9.183 e. However, no significant association was found between environmental accidents and disease incidence rates.
Conclusion: The results implied that investment in HSE management systems is not just in accordance with implementing profitability requirements, but it should be targeted and based on priorities, influenced by the results of examining root causes of diseases and accidents as well as assessing risks facing organizations.
Saeid Najafi, Shirazeh Arghami, Maryam Khazaee-Pool,
Volume 10, Issue 4 (11-2020)
Abstract
Introduction: Road traffic accidents (RTAs) have always a major concern and human factor has been recognized as their leading cause. Since taxi drivers play a significant role in accidents, the main purpose of this study was to provide a valid and reliable version of the Dula Dangerous Driving Index (3DI) for taxi drivers working in the city of Zanjan, Iran.
Material and Methods: Based on the convenience sampling method, 316 taxi (including taxi, internet taxi, etc.) drivers were recruited in this descriptive study. The 3DI contained 28 items within three factors related to dangerous driving behavior. After linguistic validation, qualitative and quantitative face validity was determined for the given questionnaire. Consequently, content validity index (CVI) and content validity ratio (CVR) were assessed by a panel of 10 experts. Internal reliability was further calculated based on Cronbach’s alpha coefficient and test-retest method.
Results: The results revealed that face validity (1.60-3.82.), CVR (0.8-1), and CVI (0.891-1) were acceptable. Cronbach’s alpha coefficient was also 0.896 for the total reliability of the instrument and 0.95, 0.89, and 0.94 for each factor, respectively. In addition, Spearman’s rank correlation coefficient was 0.871 (P-value<0.001).
Conclusion: The results ultimately demonstrated that the Persian version of the 3DI had adequate reliability, as well as, face and content validity. However, construct validity remains.
Seyedeh Maryam Taheri, Monireh Khadem, Fariborz Omidi, Alirea Sedighi, , Seyed Jamaleddin Shahtaheri,
Volume 11, Issue 1 (3-2021)
Abstract
Introduction: Pesticides are among the broadest chemical compounds used in the world and are also considered as the most dangerous compounds for living organisms. Although pesticides have significant impact on improving agricultural and food products, the processes of their production, formulation, storage, transportation, and marketing as well as the extensive use of these materials lead to occupational exposure, environmental pollution, and the presence of their residues in foodstuffs. Bentazon as a herbicide is considered as one of the most common pesticides used in agriculture and horticulture. Its effects on human health are widespread and of concern. Occupational and environmental exposure assessment of this compound is, therefore, considered necessary by conducting accurate and valid methods. The purpose of the present study was to synthesize a molecular imprinted polymer (MIP) as a specific adsorbent in the preparation process of bentazon for its selective analysis in biological matrices.
Material and Methods: For synthesis, a precipitation polymerization method was used. This method has been used to prepare particle size distribution and shape appropriately. By applying the aforementioned method, nano particle size is obtained within the sub-micron and nano range. So, crushing and sieving of the sorbent is not necessary. The MIP was synthesized with 1: 4: 30 ratio of template molecule (bentazone): functional monomer (methacrylic acid): cross-linking monomer (ethylene glycol di methacrylate), respectively. Due to particle size and high porosity, the sorption and recovery of template compound was performed faster and with higher efficiency. Some variables affecting the efficiency of MIP for sorption and desorption of analyte were investigated and optimized. They included pH of solution, MIP amount (mg), and sonication time (min) in the sorption step and volume of eluent (ml), sonication time (s), and acid percentage in the desorption step.
Results: The optimum levels of factors for the proposed method were pH of solution: 2، sonication time for sorption 7.3 min, polymer amount of 30.814 mg, acid percentage 1.1, and sonication time for desorption 165 s. According to the obtained results, the interfering factors in the matrix have no significant effect on the determination of analyte. The limit of detection (LOD) and relative standard deviation (RSD) of the optimized method were 0.79.ppb and 2.8931 %, respectively.
Conclusion: The results of this study indicated that the proposed method can be used to extract the bentazon herbicide from complex matrices such as urine samples with high efficiency and selectivity.
Fatemeh Fasih-Ramandi, Asghar Sadigzadeh, Mohammad-Javad Jafari, Soheila Khodakarim,
Volume 11, Issue 1 (3-2021)
Abstract
Introduction: Determining the size distribution of the particles for assessing their effects on human health and their control mechanisms is very effective. One of the most important equipment used in determining particle size distribution is the DMA. In this study, in addition to the design and construction of a DMA, the size distribution measurement of aerosol particles was carried out.
Material and Methods: In this experimental-laboratory study, according to the theoretical principles, the geometric dimensions and operating conditions of the DMA were determined by Fortran programs. The design of the technical drawing of the DMA was done using the Salidworks-2017 software. The DMA designing was performed by studying the size distribution of 12 ranges of DOP particles in 15 voltages.
Results: The results of applying different voltages to the DMA showed that one range of particles size had the highest number of particles in the output of the DMA at each voltage. As the number of particles with the size of 0.26-0.3 µm at 3500 volts and those larger than 2 µm at 9000 volts is the highest at the output of the DMA.
Conclusion: DMA systems are a robust tool in determining the particle size distribution. As by knowing the required voltage to separate a specific size of the particles, the DMA will be able to specify the spectrum of unknown particles.
Aysa Ghasemi Koozekonan, Mohammad Reza Monazzam Esmaeilpour, Saba Kalantary, Ali Karimi, Kamal Azam, Farideh Golbabaei,
Volume 11, Issue 1 (3-2021)
Abstract
Introduction: The skin, can be exposed to harmful factors like ultraviolet radiation (UV). Exposure to this physical hazardous agent could be contributed to pigmentation, erythemas, early aging, skin cancer, and DNA damage. The aim of this study, therefore, was to fabricate the polyacrylonitrile (PAN) nanofibers with the UV protection property by the use of various concentrations of titanium dioxide (TiO2) nanoparticles.
Material and Methods: The PAN nanofibers (10%wt) containing 0, 1, 5, 10 and 15% wt of TiO2 nanoparticles were produced using electrospinning method. The morphological propertis of nanofibers were studied by scanning electron microscopy (SEM) and the functional groups were investigated by Fourier transform infrared spectrophotometer (FTIR). The UV protection property of nanofibers was studied by measuring UV transmittance as well as calculating UV protection factor (UPF).
Results: The results showed that the diameter and morphological characteristics of nanofibers are different at various concentrations of TiO2 and increasing the concentration of TiO2 has resulted to an increase in nanofibers diameter. The analysis of FTIR results showed that TiO2 nanoparticles have been successfully loaded on nanofibers for UV protection purposes. The findings clarified that nanofibers loaded with TiO2 could increase the UV protection property up to 15%.
Conclusion: Totally, our findings show the successful fabrication of UV-protective nano webs using TiO2 nanoparticles. the new combination used in nano matcould protect employees from UV radiation.
Mehdi Amirkhani, Farbod Kouhpaye, Mohammad Reza Rajabi, Majid Najafi Kalyani, Javad Salami,
Volume 11, Issue 2 (6-2021)
Abstract
Introduction: Occupational injuries are considered as the most common work-related risk factors among the medical sciences students. Medical sciences students are mostly exposed to needle stick injuries and sharp objects when training in the clinical environment due to lack of enough experience. This study aimed at investigating the frequency of these injuries and the related causes of its occurrence among the students in various disciplines of medical sciences.
Material and Methods: This descriptive cross-sectional study was performed on the students of Fasa University of Medical Sciences in 2017. All medical, nursing, operating room, anesthesiology, and medical emergencies students were recruited to this stud using census method. Then, a questionnaire was distributed among them. The data collection tool in this study was a researcher-made questionnaire consisting of two parts of demographic characteristics and the related causes of the occurrence of injuries. After completing the questionnaire by the students, data management and analysis was performed using statistical tests and SPSS 22.
Results: The results of this study showed that 74 students (24.3%) had reported being injured caused by sharp objects at least once over their studying period of time. Twenty-six students (35.1%) described their carelessness as the main cause of the injuries. Intramuscular injection with 20 cases (27%) was the most important procedure leading to needle stick exposure. Chi-square statistical test showed that there was a statistically significant difference between the frequency of injuries caused by sharp objects and gender, so that the exposure frequency was more reported by the male students (P <0.05).
Conclusion: The results showed that injuries caused by needle stick and sharp objects are high in medical sciences students. Due to this high prevalence, in educational programs, and especially in the clinical setting, accurate and precise training and arrangements are highl recommended with the emphasis on safety measures. Also, the use of personal protective equipment (PPE), before and during working with the patient is essential for medical sciences students. In addition, due to disability of injured students, making a planning program for training them about the potential risk of these injuries is necessary.
Farhad Forouharmajd, Azam Salehi, Karim Ebrahimpour,
Volume 11, Issue 2 (6-2021)
Abstract
Introduction: one of the most important complications of exposure to ionizing radiation is emergence of cancer tumors, which happens as a result of oxidative DNA. Therefore, the present study was conducted, aimed to measuring 8-DIHYDROxy- 2’- DEOXYGUANOSINE (8-OHdG) level in radiographers’ urine as oxidative damage biomarker, as well as comparing this biomarker with cumulative effective doses.
Material and Methods: In the present study, the samples were selected into two categories, 35 of whom were from different radiography groups (including nuclear medicine, radiology, radiotherapy, CT scan), and 35 subjects were from the staff, who had no exposure to radiation. The results of the film badge were gathered from the hospitals. Since film badge monitoring period was found to be 2 months, the collective effective dose was obtained according to the respective formula for 30 last period and 6 last period. Then, at the end of the work shift, the urine samples were taken to determine the 8-OHdG concentration. The samples were obtained via the SPE (solid-phase extraction) method. After that, the 8-OHdG concentration was read by the GC/MS analyzer. Finally, the data extracted from the 8-OHdG concentration and the collective effective dose of the radiation were analyzed by SPSS software.
Results: The results showed an increase in the level of 8-OHdG, as one of the oxidative biomarkers in the body of radiographers, but the level of 8-OHdG showed a direct relation in the body of the radiographers with an average collective effective dose of radiation in the last 30 as well as the last 6 periods.
Conclusion: Observing the radiation protection principles by radiation workers results in decreased radiation and, in turn, reduces the level of oxidative stress, thus, reducing the potential effects of radiation.
Pegah Shafiei, Mousa Jabbari, Mahnaz Mirza Ebrahim Tehrani,
Volume 11, Issue 2 (6-2021)
Abstract
Introduction: Occupational accidents are one of the major challenges of the industrial workplaces. The identifying of the effective causes of the incidents occurrence, could be used to prevent them. This study was aimed to determine basic causes of occupational accidents in a vehicle manufacturing company.
Material and Methods: The occupational accidents leading to loss of time, which cause losing at least one working day, occurred from 2012 to 2017 were analyzed using the Tripod-Beta method and the causes of their occurrences were determined from the active failures to the root causes. The data were analyzed using the SPSS-22 software.
Results: Eighty percent of the occupational accidents that occurred in a vehicle manufacturing company were related to 6 root causes, i.e. the weakness of OR (20%), EC (17%), MM¬ (12%), CO (10%), IG (10%) and DE (9%). Absence of necessary authority to stop working is the most important reason for the occurrence of the weakness of Organization system with a rate of 28%.
Conclusion: By handling three root causes appropriately, i.e. improving OR, EC and MM, more than 50% of accidents can be prevented. Proper hiring of workers, exact definition of accountability and an accurate job description to the employees, proper monitoring and supervision, and near-miss recordings are suggested to reduce this incidence rate.
Rostam Esmaeili, Ahmad Ali Babaei, Ghazaleh Monazami Tehrani,
Volume 11, Issue 2 (6-2021)
Abstract
Introduction: Each country needs to preserve its human capital through preventing accidents for its development. Therefore, this study is carried out to study the relationship between safety investments and safety performance indices considering the interactive effect of the project hazard level in construction industry.
Material and Methods: This study was conducted using multiple case studies in 5 major construction worksites, in Tehran, in 2019. Data was collected using questionnaire, checklists and interview as well as evaluating the safety documents. The data analysis in this study was carried out using SPSS 18.
Results: There was a strong inverse correlation between safety investments (total safety investment, basic safety investment, and voluntary safety investment) and accident frequency rate (AFR) (r=-0.936, P-value<0.05), and there was a direct strong correlation between safety investment and safety performance (P-value<0.05, r=0.939). Also, the effect of various safety investments on safety performance indices under various project conditions (project hazard levels) was not the same; when the project hazard level was high, the effect of safety investments on safety performance was higher.
Conclusion: Increasing safety investment improves safety performance through decreasing the accidents. Also, investment in both safety components (basic safety investment and voluntary safety investment) might improve safety performance. The results of the current study can be used as a basis by the contractors and construction companies to invest in safety and to determine proper budget for managing safety of construction projects.
Seyedeh Farima Navidi, Ali Safari Variani, Sakineh Varmazyar,
Volume 11, Issue 2 (6-2021)
Abstract
Introduction: Work-related musculoskeletal disorders (WMSDs) are one of the most important causes of absenteeism, increased costs and human injuries, which are very common in computer users. The purpose of this study was to investigate the effect of 8 weeks of corrective exercise on reducing the prevalence of musculoskeletal disorders (MSDs) in computer users working in a gas company.
Material and Methods: This cross-analytical study was conducted on 101 computer users working in a Gas Company in Qazvin city in 2019. Fourteen people participated in 8 weeks correction training intervention program (16 sessions in 1 hour and 2 times a week). Nordic questionnaire and body map were used in order to investigate the prevalence and severity of MSDs. The data were analyzed using Kolmogorov-Smirnov, Cramer V, McNamar, Paired sample t-test and Wilcoxon tests in SPSS version 23 software.
Results: The most common disorders were shoulder (64.3%), waist (42.9%) and neck (35.7%) regions among computer users during the last week before intervention. The prevalence of MSDsby strength and flexion exercises in neck and shoulder regions with 95% and 99% confidence showed a significant decrease before and after intervention. The incidence of discomfort in the waist region decreased by 35.8% after intervention and in other regions decreased by at least 7.1%.
Conclusion: The results of this study showed that implementation of corrective training intervention program by exercise specialists can increase muscle stretch and consequently decrease the prevalence of MSDs7.1%- 64.3%.
Mehrdad Hajihasani, Farideh Hajihasani,
Volume 11, Issue 3 (9-2021)
Abstract
Introduction: As an important problem, occupational procrastination is associated with organizational efficiency. Alhough this problem has received lots of attention from researchers, scant research has been conducted on the role of psychological hardiness and marital conflict in Shahrekord university staff. The main purpose of the present research was to predict occupational procrastination based on psychological hardiness and marital conflict in Shahrekord university staff.
Material and Methods: This was a descriptive-analytical cross-sectional study. The research population consisted of Shahrekord university staff in 2017. The research sample (n=168) was selected using a convenience sampling method. The tools implemented were Occupational Procrastination Scale (Saffarinia and Amirkhani, 2011), Lang and Goulet Hardiness Scale (2003), and Marital Conflicts Questionnaire of Barati and Sanaei (2006). The obtained data was analyzed using descriptive statistics (mean and standard deviation), Pearson correlation tests, and multiple linear regression analysis.
Results: The results of Pearson correlation showed that the relationships between psychological hardiness and occupational procrastination (r = -0.316, P <0.001), and marital conflict and occupational procrastination (r = 0.511, P<0.001) were significant. The results of multiple linear regression showed that marital conflict (B = 0.347, P<0.001) was predictive of occupational procrastination and explained 27.8% of the variance of occupational procrastination in Shahrekord university staff.
Conclusion: The obtained results showed that the occupational procrastination in Shahrekord university staff can be predicted through marital conflict. Therefore, this variable is recommended to be considered in investigating procrastination in Shahrekord university staff.
Adel Mazloumi, Ramin Mehrdad, Zeinab Kazemi, Zahra Vahedi, Leila Hajizade,
Volume 11, Issue 3 (9-2021)
Abstract
Introduction: Musculoskeletal disorders (MSDs) are prevalent in work settings and are associated with high rate of prevalence and costs. Musculoskeletal conditions have multifaceted nature, and occupational factors play an important role in their development. The aim of this study was to identify the risk factors of work-related musculoskeletal disorders in the working population in Iran during 2000 to 2015.
Material and Methods: Using the appropriate search terms, articles published in the journals, student thesis, and those presented at the conferences were searched through authentic English databases (Google Scholar, Scopus, PubMed) and Farsi ones (Magiran, SID, IranMedex, Irandoc). Following removal of duplicate citations and irrelevant studies, the full texts of the remaining publications were prepared and assessed for more detail.
Results: Perceived discomfort in low back region obtained the highest score in workers of industrial, administrative, service, and agricultural settings. However, in the handicraft and educational groups, the highest percentage of discomfort was belonged to neck (66.7%). Findings showed that the most commonly used techniques for evaluation of musculoskeletal disorders and risk factors were, respectively, Nordic questionnaire (NMQ) (76%) and REBA (13.9%). Moreover, all identified risk factors were classified into eleven groups including: biomechanical, work environment design, tools, equipment, temporal aspects of job design, job content, organizational aspects, economic and financial issues, social aspects, individual characteristics, and training.
Conclusion: Overall, a wide range of risk factors reported in the previous studies were categorized in the present review. The results are suggested to be considered by managers and decision makers as a framework to take measures for controlling musculoskeletal disorders to accomplish the goal of ergonomics, which is productivity and well-being.
Maryam Babaei, Sahar Rezaian, Seyed Ali Jozi,
Volume 11, Issue 3 (9-2021)
Abstract
Introduction: Comprehensive and reliable performance evaluation of organizations has always been one of the main concerns of stakeholders and managers of organizations. Performance evaluation can raise awareness of the progress made in improving the performance of any organizations, especially in the field of health, safety, and environment (HSE) and thus, create the necessary motivation and opportunity to improve the quality of HSE performance. National quality awards and excellence approaches emphasizes the fact that survival in global competition requires improving the performance of organizations on a global scale. The EFQM enterprise excellence model, as a comprehensive tool with a comprehensive approach to all aspects of organizations, helps managers to understand their organization well.
Material and Methods: This study was conducted in Tehran Industrial Group in 2018, during which the performance of this industrial group in the design and construction of one of the dams in the south of the country was evaluated and analyzed. The data collection tool was a standard self-assessment questionnaire based on the EFQM enterprise excellence model, the validity and reliability of which was tested by Cronbach’s alpha coefficient at 0.971.
Results: In terms of “enablers” criteria, the leadership dimension, with a score of 76.36, obtained the best percentage of scores, while the processes criterion with a score of 72.04 had the lowest percentage of scores. This dimension, along with staff, resources, and partnership dimensions, needs to be improved. In the field of “results” criteria, the key performance results with 79.77 points had the best percentage and the customer result dimension with a score of 69.13 had the lowest, indicating that the organization should improve these sectors.
Conclusion: The results indicated the suitable status of the organization in terms of the criteria of excellence model. The results of this model are generally used for systematic analysis of the organization in order to achieve a comprehensive view of the organization and its challenges.
Mahta Fooladi, Roxana Moogouei, Seyed Ali Jozi, Farideh Golbabaei, Golnaz Tajadod,
Volume 11, Issue 3 (9-2021)
Abstract
Introduction: Phytoremediation is one of the available techniques for removing the volatile organic compound from the air. Benzene and toluene are volatile organic compounds that exist in many occupational environments. Plants are able to reduce benzene and toluene in the air and the use of plants is a simple and consistent solution for the nature to reduce these compositions in the air and improve the air quality of work environments. The phytoremediation potential of Dannae racemosa and Hedera helix were evaluated for remediation of benzene and toluene in air.
Material and Methods: Dannae racemosa and Hedera helix were exposed to exposed benzene(250ppm) and toluene(250ppm) each time alone in a chamber and to examine the decrease amount of benzene and toluene during 6 days. Then plants were exposed to 250ppm and 250ppm of benzene three times with a rest day and the processes of reduction were investigated.
Results: Dannae racemosa was able to remove all of benzene and toluene concentrations from the air after 6 days. Hedera helix was able to reduce all of benzene and toluene concentration from the air after 6 and 5 days, respectively. The differences in Benzene and toluene remediation were assessed between the first and the third subsequent exposure and the results showed that the reduction rate increased for Dannae racemosa.
Conclusion: It can be concluded that the Dannae racemosa and Hedera helix could be used for benzene and toluene phytoremediation.
Samira Barakat, Behnam Moradi,
Volume 11, Issue 3 (9-2021)
Abstract
Introduction: Long-term exposure to hand-arm vibration causes musculoskeletal disorders mainly in hand and shoulder. The purpose of this study was to determine the effect of sport and using anti-vibration gloves on the grip strength of workers exposed to the hand-arm vibration.
Material and Methods: In this descriptive-interventionist study, 41workers working in one of the Isfahan metal industries were studied. Data were collected by the demographic questionnaire, hand-arm vibration acceleration measurement was performed based on the ISO 5349 standard and grip strength was measured using the dynamometer device model Jamar. The investigations were performed on 3 groups including sporting moves, using of anti-vibration gloves and combination of sporting move and using of gloves. Twenty workers were selected as control group without exposure to any hand-arm vibration. Data were analyzed by the SPSS-21 software.
Results: Workers’ grip strength difference was significant before and after vibration (PValue<0.001) and grip strength had significant and inverse relation with vibration (PValue<0.001, R= -0.411). Grip strength was higher in the group that used anti-vibration gloves accompanied with the sporting moves compared to before the intervention and significant relation was observed (PValue<0.001).
Conclusion: Vibration affects decreasing in grip strength and grip strength itself can be used as a screening measure for those workers exposed to the risk and diseases related to the vibration. Regular sporting moves and using anti-vibration gloves are effective on improvement of workers’ grip strength and preventing vibration-induced complications.
Vida Zaroushani, Romina Abbasnejad,
Volume 11, Issue 3 (9-2021)
Abstract
Introduction: Considering the importance of identifying and tracing primary sources of Covid-19 crisis in infection control, this study was carried out with the aim of identifying the occupational tasks effective in transmitting Covid-19 in the event of death of a female staff in medical record unit in Shafa Takestan Hospital (Qazvin Province).
Material and Methods: This case study was performed on the death of a 26-year-old married woman working in the medical records department of Shafa Takestan Hospital in March 2019. After identifying and completing the tasks, hazards analysis was performed and finally, various tasks and amount of the Covid-19 sources were determined.
Results: Covid-19 risk sources are classified into three groups of human resources with 51 cases (38.06%), office tools and equipment with 46 cases (34.33%) and paper with 37 cases (27.61%). Four tasks were identified as major tasks with a 59.90% of the total number of COVID-19 risk sources. In this study, two critical tasks were determined with the titles of “reply to requests of forensic medicine and insurance” and “reviewing patients’ surgical reports” that contained a total of 39.06% of the Covid-19 sources.
Conclusion: The results showed that the human resources in two major tasks were the most critical sources of Covid-19. So, the control of these critical tasks is of special importance. The results also showed that it is necessary to transfer the special and unusual tasks to the time after the crisis, in order to reduce the sources of Covid-19 contamination.
Davood Mahmoudi, Jalil Nazari, Leila Rastgoo, Mohammad Asghari Jafarabadi,
Volume 11, Issue 3 (9-2021)
Abstract
Introduction: The carpet industry is one of the most important handicrafts in Iran. This industry is one of the most difficult and harmful professions, in which the employees are often working in a workplace with non-ergonomic, unsafe, and unhealthy conditions. The present study aimed to address the modeling of the individual, job characteristics, and workplace conditions with the general health of carpet weavers through an ergonomic approach.
Material and Methods: The current study was a descriptive-analytic survey. The study population was female workers, who have had a minimum of one-year work experience and working in the workshops located in Meshginshahr city villages. The data collection tool was a combination questionnaire including, Goldberg’s questionnaire (GHQ-28), NIOSH questionnaire (disease history section), and questions about workplace conditions. The obtained data were entered into SPSS-17 software and analyzed statistically using statistical modeling based on the general linear model, multivariate and other statistical tests.
Results: Unpleasant condition was observed among the 37.4% of the examined, in terms of general health. Logistic regression modeling was used to investigate the internal and external factors of carpet weavers with their general health status. According to the model, general health has a significant relationship (p<0.05) with most of the internal factors such as age, marital status, history of disease, etc. However, there was no significant relationship with the workplace conditions.
Conclusion: According to the results of this study, it can be concluded that demographic and job variables are of the most important factors affecting the general health of carpet weavers. Although in the model, the workplace conditions did not show any significant relationship with the components of general health, interpreting these findings requires more studies. More studies are required objectively to identify the effect causes of the general health of carpet weavers (especially workplace conditions).
Mohammad Yadegaripour, Malihe Hadadnezhad, Ali Abbasi, Fereshteh Eftekhari,
Volume 11, Issue 4 (12-2021)
Abstract
Introduction: Low back pain is one of the most common musculoskeletal disorders leading to disability around the world. Several studies have suggested that prolonged computer/ laptop work contributes to the development of low back pain and discomfort. The results of the studies conducted on the association of back discomfort and muscle activity are contradictory. Thus, the present study aims to evaluate the relationship between the activity level and relative rest time of the trunk muscles with back discomfort while working with a laptop in a sitting position.
Material and Methods: First, 20 young healthy males performed laptop work including mouse work and typing in conventional and ergonomic setups. In the ergonomic setup, the screen height and keyboard placement were specifically adjusted for each individual. In addition, the electromyographic activity of the lumbar erector spinae, right and left multifidus and transversus abdominis, rectus abdominis, external oblique muscles, and the posture of the lumbar spine were recorded in the first and last two minutes of an 8-min task. After the end of each task, the participants scored their back discomfort.
Results: The results showed a positive correlation (r=0.57 and p=0.009) between back discomfort and the EMG amplitude of the lumbar erector spinae muscle. In addition, back discomfort was negatively correlated to the relative rest time of the multifidus muscle (r=0.50 and p=0.023), and a positive correlation was reported with the relative rest time of the transversus and rectus abdominis (r=0.47, p=0.039, and r=0.45, p=0.049, respectively).
Conclusion: The relative rest time of the trunk muscles may be a better index than that of the EMG amplitude to highlight the risk factors for back discomfort. However, a causative link between muscle activity and discomfort cannot be implied from this study. The current results do not undermine the role of other factors associated with the increased level of discomfort during sitting.
Milad Abbasi, Mohammad Reza Monazzam, Mansour Shamsipour, Hossein Arabalibeik,
Volume 11, Issue 4 (12-2021)
Abstract
Introduction: There are several generic and specific models to assess the individual job performance (IJP). While these methods may provide the valuable information, none of them cover the complexity and wide range of the behaviors which express the IJP. This review study aimed to identify all existing models and incorporate them to achieve a comprehensive conceptual model to assess the IJP.
Material and Methods: Databases such as PubMed, Scopus, Embase, and ProQuest were systematically searched to meet the study’s goals. Moreover, references to relevant publications were examined. Finally, suitable publications were discovered and analyzed using the inclusion and exclusion criteria.
Results: The results of Search in databases, including PubMed, Scopus, Embase, and ProQuest, showed that 12754 articles were found in the initial search. After removing duplicate and unrelated articles, finally, 155 eligible articles were selected. Based on full-text screening, 10 studies were excluded, and 5 studies were not accessible. Finally, by checking the references mentioned in the selected articles, 4 more eligible articles which were not retrieved in the search strategy were added; finally, 61 articles were selected to be reviewed. Ninteen articles were related to the general models, and 19 articles addressed job-specific assessment models. The remaining 23 articles described other existing models.
Conclusion: To evaluate IJP, a heuristic structure was developed based on the literature research. These dimensions were selected because they can accommodate all of the preceding models’ dimensions. They also include any behaviors that may have an impact on IJP.
Hosseinali Rangkooy, Maryam Mosavi Ghahfarokhi, Behzad Fouladi Dehaghi,
Volume 11, Issue 4 (12-2021)
Abstract
Introduction: Ethylbenzene is a volatile organic compound used in many industries, including oil and gas, oil colored and insecticides. Due to the toxic effects of this chemical substance, control and elimination of this vapor is necessary. Photocatalytic degradation is a possible method to remove organic compounds from air. This study was performed to determine the efficiency of photocatalytic removal of ethylbenzene vapor using ZnO nanoparticles immobilized on modified natural zeolite.
Material and Methods: Natural zeolite was first modified with hydrochloric acid and then with diphenyl dichlorosilane. Next, zinc oxide nanoparticles were stabilized on the zeolites. Dynamic air flow and different concentrations of ethyl benzene (25, 50, 100 and 200 ppm) were produced and the removal efficiency of ethylbenzene vapor was investigated using UV/MZe/ZnO. The temperature and relative humidity were set at 25±2°c and 35%. The surface and volume of the pores of the bed were determined by the BET method and surface structure was determined by Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD).
Results: Evaluations for BET showed the specific surface areas decreased by increasing the amount of ZnO. XRD analysis and SEM images showed that zeolite structure was stabled and nanoparticles was successfully stabilized on Ze. The results showed that the highest removal efficiency (50.8%) by the process of UV/MZe/ZnO at concentration 25 ppm.
Conclusion: The result of this study showed that the Ze/ZnO catalyst may be an applicable and hopeful method to removal of ethylbenzene from air flow under UV irradiation