Showing 114 results for Di
Morad Rezaei Dizgah, Fardin Mehrabian, Mohsen Jani Pour,
Volume 8, Issue 1 (4-2018)
Abstract
Introduction: Job Satisfaction is a perception that improves employees’ productivity, motivation and empowers them. Therefore, recognizing the factors affecting it and paying attention to emotional intelligence can provide the basis for increasing job satisfaction.
The purpose of this study was to investigate the effect of emotional intelligence on job satisfaction considering the mediator role of job burnout, emotional Labor, emotional inconsistency, personality deprivation and deficiency of individual success in the Staff of Guilan University of Medical Sciences
Material and Method: This research used descriptive and cross-sectional method. The study population included 413 staffs from the faculties of Guilan University of Medical Sciences. The sample was determined 200 people using Cochran’s formula. A standard questionnaire was used to collect data. Content validity was done for this questionnaire and also its reliability studied using Cronbach’s alpha coefficient. Descriptive statistics and structural equation modeling were used to analyze the data using Lisrel software.
Result: The results showed that emotional intelligence affects emotional inconsistency, emotional exhaustion, emotional Labor, job satisfaction, deficiency of individual success and deprivation of personality. Also, emotional inconsistency affects on emotional exhaustion, deficiency of individual success, job satisfaction and personality deprivation. In addition, the results show that emotional exhaustion affects deprivation of personality, deficiency of individual success and job satisfaction and finally, the deficiency of individual success affects job satisfaction.
Conclusion: Considering the relationship between job satisfaction with job burnout, emotional intelligence and emotional inconsistency, it would be helpful for managers to implement programs to increase employee satisfaction and self-efficacy and provide a context for reducing job burnout.
Ali Khavanin, Ahmad Jonidi Jafari, Ali Safari Variani, Vida Zaroushani,
Volume 8, Issue 1 (4-2018)
Abstract
Introduction: Nowadays, demand for protection against radar radiation using electromagnetic shielding is on the rise. Double-layer or multilayer shielding were devised in order to improve the single layer electromagnetic shielding properties. In this study, we tried to prepare a new double-layers electromagnetic shield and investigate the effect of structural factors such as thickness, similarity in layers and mixing time on the shielding effectiveness for double-layers shields.
Material and Method: This study used the Resin Epoxy EI-403 and Nickel Oxide nanoparticles to prepare single layer shields by casting method (with two different mixing time: 10 and 66 min) in 2, 4 and 6 mm thicknesses and 7 wt% Nickel oxide nanoparticles. Then, in order to prepare double-layers shields, single-layer shields were placed on each other without air space. Scattering parameters were measured by a Vector Network Analyzer (V.N.A) and shielding effectiveness were calculated in X-band radar frequency range.
Result: The highest and the lowest averages of shielding effectiveness in single layer shields were 84.14% and 46.05%, respectively. These values were 66.34% and 41.99 %, in double layers electromagnetic shields. The averages of shielding effectiveness values in the double-layers shields (with 10 min in mixing time) in 6, 8 and 10 mm in thickness were 41.99%, 45.45% and 43.25%, respectively. These values in 66 min in mixing time, increased to 54.30%, 62.07% and 66.34%, respectively.
Conclusion: In this study, the shielding effectiveness in double-layers were less than single layer electromagnetic shields. Although the increase in mixing time improved the shielding effectiveness of both single and double layer shields, it could not increase the shielding effectiveness in double layer shields in comparison with single layer. Also, the increase in mixing time in double-layer shields showed that shielding effectiveness decreased with increasing thickness in these shields. Also, it was seen that using a similar single-layer shield in the structural of a double-layer shield led to an increase in skin depth and multi reflections .It finally reduced the shielding efficiency in double layer. It is suggested that in the future, other studies be conduct to improve the shielding effectiveness in these electromagnetic shields.
Mahsa Mapar, Mohammad Javad Jafari, Nabiollah Mansouri, Reza Arjmandi, Reza Azizinejad,
Volume 8, Issue 1 (4-2018)
Abstract
Introduction: The responsibility of achieving sustainable development goals in most megacities and subsequently in Tehran megacity are in charge of the municipalities. Since, the goal of municipalities in environmental-friendly activities is to protect the physical and mental health of citizens. Therefore, the sustainability assessment of health performance in municipalities is one of the most significant issues in the field of municipal sustainable development of megacities. The Objective of this study was to develop a tool for assessing the sustainability performance of Tehran municipality in the field of health- related activities and services.
Material and Method: In this research the main sustainability indicators in the field of health performance were extracted and localized by providing an indicator-based tool for Tehran municipality as a case study. To determine the initial set of effective indicators, guidelines and standards related to health sustainability issues were surveyed, and an initial set of indicators were extracted. Afterward, a two-round Delphi method was applied by 12 qualified experts to select the most robust indicators of Health performance and assign the importance of the inclusion for each proposed indicator on a seven-point Likert scale. The mean value set to 70% and the standard deviation less than 1 were considered as the cut value.
Result: The findings resulted in extracting 11 main categories and 28 sustainability indicators of health performance. The set of indicators related to the “green space” and “waste” categories with slight differences gained the first and second position in the health sustainability field respectively, whereas “urban planning”, “active and healthy life” and “health and hygienic services” located in the bottom of the list with the relatively close scores.
Conclusion: The results of this study showed that due to little difference between the score of the main selected categories (less than 1 point difference between the highest and lowest categories) and also due to the fact that the expert panel reached a consensus on the total 11 categories, therefore in order to achieve municipal sustainable development and improving the health level of citizens in the future, it is essential to have a robust consideration toward applying engineering and management measures against all 11 selected categories.
Hamidreza Heidari, Hoda Rahimifard, Abolfazl Mohammadbeigi, Farideh Golbabaei, Robabeh Sahranavard, Zahra Shokri,
Volume 8, Issue 1 (4-2018)
Abstract
Introduction: Considering the necessity of evaluating novel thermal indices for different individual and environmental conditions, the aim of this study was validation of a new enthalpy index for evaluation of heat stress in hot and dry climate.
Material and Method: In this descriptive analytical 97 city services outdoor workers were randomly selected and evaluated in spring and summer seasons in Qom city, Iran. Correlation between new enthalpy index and standard WBGT index, as well as physiological response of deep body temperature was studied and analyzed.
Result: Findings showed that regardless of the time of measurements, correlation between enthalpy and WBGT index was better than its correlation with tympanic temperature (R2= 0.756 versus R2= 0.391). Considering the time of measurement, it was found that with increasing temperature and decreasing humidity, the correlation between indices was reduced, although the correlation ratio was maintained similar.
Conclusion: Due to the simplicity of the enthalpy index measurement ,its independency to measure the globe temperature and the possibility of estimation of this index using daily climate parameters in meteorological stations, and on the other hand, appropriate validity of enthalpy against WBGT and core temperature, it can be a good alternative for WBGT index and as a screening index for thermal environments in hot and dry condition.
Asghar Ghahri, Farideh Golbabaei, Leila Vafajoo, Seyed Mohammad Mireskandari, Mehdi Yaseri, Seyed Jamaleddin Shahtaheri, Faranak Najarian,
Volume 8, Issue 2 (6-2018)
Abstract
Introduction: Anesthetic gases used in hospitals include N2O and halogenated hydrocarbons (such as sevoflurane) which can be released through leakages and uncontrolled exhalation by the patient into the ambient air of clinical staff. These gases have greenhouse effect and damage to the ozone layer and serious risks such as reproductive, preterm delivery and fetal abnormalities and increased spontaneous abortion on the health of operating room personnel. Therefore, removal of these gases from the workplaces is essential especially in the treatment centers. The purpose of the present study was to investigate the adsorption of sevoflurane from air by using activated Charcoal and also the effect of acid modification on its performance.
Material and Method: In this study, two adsorbents of unmodified and modified activated charcoal with nitric acid were used to remove sevoflurane. After preparation, the adsorbents were characterized using XRD, FT-IR, BET and FE-SEM methods. After characterization, the breakthrough and adsorption capacity of sevoflurane on both adsorbents were determined using the modified wheeler equation.
Result: The results of characterization showed that acid modification did not affect the crystalline structure of activated charcoal and increased the adsorption and microporous of acid-modified activated charcoal in comparison with unmodified activated charcoal. It also reduces surface functional groups of the activated carbon. The results of determination of adsorption capacity indicated that the adsorption capacity of modified activated charcoal was improved in comparison with unmodified activated charcoal.
Conclusion: The results demonstrated that both adsorbents have the ability to absorb sevoflurane and modified activated charcoal have a better performance in this process. This effect may be due to the surface area of adsorption and volume of micro pores more than the unmodified activated charcoal.
Masoumeh Lotfi, Mohammad Reza Monazzam Esmaielpour, Nabeioallah Mansouri, Saeid Ahmadi,
Volume 8, Issue 2 (6-2018)
Abstract
Introduction: Using diesel generators is necessary for activities like welding in construction sites and it is often accompanied with noise pollution. The aim of this study was to evaluate noise pollution induced by diesel generators in construction activities in one of the districts of Tehran city.
Material and Method: In this descriptive study, 14 construction sites were selected for the evaluation of noise pollution in Tehran, district 4. Background and diesel generators sound pressure level were measured in accordance with BS 5228(2015) and noise guidance in the area around the construction sites. Diesel generators sound pressure level at 4 points and also the audio frequency analysis, one meter away from the device was measured at a random locations around it. TES-1358, Type 2(Taiwan) sound level meter was used to measure sound pressure level and calibration was performed before and after noise measurement. The validated Noise annoyance questionnaire adopted from ISO15666 standard, completed by the residents. T test, correlation and analysis of variance was performed to analyze data using SPSS software ver. 22.
Result: The mean equivalent sound level of diesel generators background noise were respectively 76 ± 4.05 dB(A) and 46.2 ± 1.09 dB(A) around the construction sites. Diesel generators noise around the construction sites was higher than the noise limit (background noise plus 5 dB)(P Value <0.05). The highest (95.3 ± 0.33 dBA) and lowest (90.9 ± 0.63 dBA) average sound pressure level was related to Benz355 and Perkins generators. One-way ANOVA statistical analysis showed significant differences in the average sound pressure level of various diesel generators between the devices (P Value <0.05). The mean sound pressure level among 190 sound monitoring stations in the interior parts of the construction sites were about 81.11 ± 4.6 dB(A). The experienced noise annoyance was evaluated higher than the average by 73.4 percent of residents. Residents’ noise annoyance and noise level around construction sites were significant using Pearson correlation (R=0.486, P value <0.05). Dominant noise frequency and associated sound pressure level of diesel generators were measured 63 Hz and 84.4 dBA, respectively.
Conclusion: Diesel generators noise in the area around the construction sites was higher than the environmental noise limit and it was accompanied with abundant noise annoyance for residents around these construction sites. Therefore, due to the lack of environmental rules related to construction industry noise pollution in Iran, assessment and approving of such rules is essential to reduce noise annoyance in urban areas.
Masoud Hamerezaee, Farideh Golbabaei, Parvin Nasiri, Kamal Azam, Somayeh Farhang Dehghan, Asad Fathi, Faezeh Darabi,
Volume 8, Issue 2 (6-2018)
Abstract
Introduction: Heat stress is one of the hazardous agents in the steel industries which can threaten the health and safety of workers and lead to serious occupational diseases. The aim of the study was to assess the heat stress in the steel industries and compare PHS (Physiological Strain Index), WBGT (Wet-Bulb Globe Temperature), DI (Discomfort Index) and HSI (Heat Stress Index) indices for the estimation of heat stress and to determine the optimum index for steel industries.
Material and Method: This descriptive-analytic study was conducted among 220 workers engaged in two steel industries in Iran. Environmental and physiological parameters were measured according to ISO 7726 and ISO 9886 in three times of measurement, and finally the time-weight average of the heat stress indices were calculated. All data were analyzed using SPSS ver. 20.
Result: The time-weight average of WBGT (28.28 oC), DI (29.11 oC), HIS (65.7 %) indices were higher than the recommended limits. Physiological parameters (oral, tympanic and skin temperatures, systolic and diastolic pressures and heart rate) had the greatest value in the second time of measurement (afternoon). WBGT index comparing to the PHS, DI and HSI indices had highest correlation with oral, tympanic and skin temperatures and heartbeat (r=0.314 , 0.408 , 0.459 , 0.302, respectively; P < 0.05), while systolic and diastolic blood pressures showed no significant correlation with WBGT (P > 0.05). The WBGT index had the highest correlation with studied indices which was 0.945, 0.681 and 0.600 for DI, PHS and HSI, respectively.
Conclusion: This study assessed the optimal index with regard to the physiological parameters, and it was concluded that the WBGT index has the highest correlation with the most of physiological parameters, and therefore, WBGT index can be the most optimum index to heat stress assessment in the studied steal industries.
Mohammad Hamid Ijazi, Sara Salarian, Majid Bagheri Hosseinabadi,
Volume 8, Issue 2 (6-2018)
Abstract
Introduction: Mercury, in different form can induce adverse effects on various organs especially central nervous system. The aim of this study was to determine concentration of mercury in inhalation and urine of the exposed worker and to investigate the prevalence of probable neurobehavioral disorders.
Material and Method: The present case-control study was conducted among workers of a unit in a petroleum industry. The study population consisted of 52 workers as case and 63 workers as control groups. The mercury concentration in air and urine was measured according to NIOSH 6009 standard and using the cold vapor atomic absorption spectrophotometer (CV-AAS). Demographic data and neurobehavioral disorders were collected using a self-reported questionnaire. Pearson correlation coefficient, multiple regression tests and SPSS v24 were used to analyze the data.
Result: Air concentration of mercury was 0.062 ± 0.0014 mg/m3 which was higher than the recommended threshold by NIOSH and ACGIH. In addition, there was a significant difference between urinary concentration of mercury in the case (37.73 ± 13.01 µg/g cratinine) and control (5.93 ± 4.76 µg/g cratinine) groups (p=0.03 6). Based on the multivariate logistic regression model, significant relationships were found between memory loss, sleep disturbance, and urine mercurial concentrations and, between memory loss, moody, muscle weakness and air mercurial concentration.
Conclusion: The values of Hg in blood and urine workers who worked in investigated unit were significantly higher than recommended threshold values. In addition, the Hg concentration in urine was related to some of neurobehavioral disorders.
Mohammad Javad Jafari, Hassan Assilian Mahabadi, Gholam Heydar Teimori, Mohsen Attar, Soheila Khodakarim,
Volume 8, Issue 3 (9-2018)
Abstract
Introduction: Workers in open pit mines are frequently exposed to extreme heat stress during hot seasons. Several indices including Modified Discomfort Index (MDI) are used to evaluate the heat stress. The aim of this study was to evaluate the MDI and to investigate its relationship with ISO 7243 standard (Wet Bulb Globe Temperature index, WBGT) and physiological parameters of workers in an open pit mine.
Material and Method: This cross-sectional study was conducted among 120 healthy male miners in an open pit mine during summer season in 2014. Physiological parameters including body core and skin temperature, heart rate and blood pressure were measured according to ISO 9886 standard. All environmental and physiological parameters were simultaneously measured and recorded during a work shift. The MDI and WBGT indices were calculated using the related formula. Statistical analysis was performed using the SPSS 22 software.
Result: According to the criteria of MDI, about 29 percent of workers had the average level, 68 percent of workers experienced the intense level and 2.5 percent suffered from the extreme level of exposure to the heat stress. No case of light level exposure to heat stress was obtained among workers. A significant correlation was found between MDI and ISO standard index (WBGT). Statistically significant correlation were also found between MDI and physiological parameters (P<0.001); in which the highest correlation coefficient was found for the heart rate variable (r=0.589).
Conclusion: Based on MDI, a high percentage of open pit mine workers were at risk of heat stress hazards. MDI had a moderate correlation with physiological parameters of the workers and showed a remarkable correlation with the WBGT.
Maryam Ramin Sabet, Mehran Pourhossein, Monireh Khadem, Fariborz Omidi, Farideh Golbabaei, Seyed Jamaleddin Shahtaheri,
Volume 8, Issue 4 (12-2018)
Abstract
Introduction: Measurement of pesticides in biological matrices is become a serious challenge for researchers due to their very low concentration in different matrices. The aim of this study was to develop a new sample preparation method with high accuracy and validity and short retention time for determination of diazinon.
Material and Method: Dispersive liquid-liquid micro-extraction technique coupled with high performance liquid chromatography equipped with ultra violet detector was developed for trace extraction and determination of diazinon pesticide in human urine samples. One variable at a time method was used to optimize parameters affecting the diazinon extraction. Different parameters such as extraction solvent, disperser solvent, and volume of the extraction solvent, volume of the disperser solvent, centrifugation time and speed, salt addition, and sample pH were studied and optimized.
Result: Findings showed that optimal levels of these variables for diazinon pesticide were 150 μl of carbon tetrachloride as extraction solvent, 1.5 ml of methanol as dispersive solvent, pH of 6, 5 minutes centrifuge time at speed of 4000 rpm , 0% (w/v) salt addition. Correlation coefficient was 0.9965 indicating the linearity of a wide range of concentrations of the toxin. LOD and LOQ was calculated less than 0.7 and 5 µg L-1 respectively. The relative standard deviation for six replicate experiments in intra-day and inter-day at tree selected concentrations (50, 200 and 1000 µg L-1) was less than 4% that indicates the accuracy and precision of the optimized method. Enrichment factor and extraction recovery for diazinon were 245 and 99% respectively.
Conclusion: According to the results, dispersive liquid-liquid micro-extraction procedure was successfully developed for the extraction of diazinon from human urine samples. Compared to other extraction techniques, the proposed procedure had some advantages such as shorter extraction time, better reproducibility, and higher enrichment factor.
Davoud Mahmoudi, Seyyed Shamsaddin Alizadeh, Yahya Rasoulzadeh, Mohammad Asghari Jafarabadi,
Volume 8, Issue 4 (12-2018)
Abstract
Introduction: 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 Method: 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.
Result: 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.
Conclusion: 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.
Saber Moradi Hanifi, Leila Omidi, Gholamreza Moradi,
Volume 9, Issue 1 (4-2019)
Abstract
Introduction: Fire and explosion are the most common consequences of natural gas pipeline accidents. The results of previous studies showed a higher rate of accidents in natural gas transmission lines. Given that a large number of people living in the vicinity of natural gas pipelines with a higher severity of related accidents. The aim of current study was to estimate risks using the method of quantitative calculation of risk and simulation of natural gas pipeline leakage using areal locations of hazardous atmospheres (ALOHA) in natural gas power generation.
Material and Methods: The method of quantitative calculation of risk was used to identify and prioritize risks. The simulation of the consequences of natural gas pipeline leakage was done by ALOHA software. Calculations of individual and social risks were performed based on statistical data obtained from the literature.
Results: The most serious effect of natural gas pipeline leakage was heat radiation effect of jet flame. Considering three leakage apertures in the natural gas pipeline 80, 130, and 300 mm, individual risks for each leakage aperture were 0.073, 0.114, and 0.569 and the number of deaths was 115, 400, and 3386, respectively. Increases in the leak aperture can lead to an increase in the number of deaths and decrease in the cumulative rate of accidents.
Conclusion: The most serious consequence of natural gas pipeline leakage was heat radiation effect of jet flame. The individual risk and social risk are beyond the acceptable risks range.
Hossein Marvimilan, Iraj Mohebbi, Hamidreza Khalkhali, Mohammad Hajaghazadeh,
Volume 9, Issue 1 (4-2019)
Abstract
Introduction: Physical workload is one of the main risk factors in developing of musculoskeletal disorders in construction workers. The current study was carried out to determine the prevalence of musculoskeletal disorders and its relationship with demographic characteristics and physical work load index (PWLI)in construction workers.
Material and Methods: This investigation was a descriptive and cross-sectional study in which 162 subjects including 75 rebar and 87 bricklayer workers were participated. Nordic musculoskeletal and physical workload questionnaires were employed as the tools of this study. Chi-squared and logistic regression tests were used for statistical analysis in SPSS 21 software.
Results: The mean of age and working experience of construction workers were 34.6±8.6 and 11.2±6.8 years, respectively. The most prevalent symptoms were in the body regions of upper back (57.4%), lower back (35.8%), and neck (30.2%). In the univariate analysis, the musculoskeletal symptoms of shoulders, low back, feet, knees, and thighs with PWLI and the upper back pain with age, working experience, and working hours had significant relationships (P<0.05). According to logistic regression analysis, with the increase of the value of PWLI to more than 90 percentile, the chance of having symptoms of musculoskeletal disorders in low back, knees, and feet and also with the increase of working hour to more than 8 hours, the chance of having symptoms in low back and feet increased significantly.
Conclusion: The prevalence of musculoskeletal disorders was high in the studied construction workers. Most of the musculoskeletal symptoms were correlated with PWLI. Therefore, PWLI could be used to determine the construction jobs with the high risk of musculoskeletal disorders. To reduce the symptoms of musculoskeletal disorders in construction workers, the reduction of sources of physical workloads such as heavy material handling and awkward postures are proposed. It is also recommended that the working hours be limited to less than 8 hours.
Masoumeh Sadri Khanlou, Mohammadreza Monazzam, Kamal Azam, Alireza Mortezapour, Seyed Abolfazl Zakerian,
Volume 9, Issue 3 (9-2019)
Abstract
Introduction: Nearly a third of people work in jobs that use voice to be part of their work. Teachers as the largest group of professional vocal users, are at risk of vocal disorders. The aim of this study was to investigate the effect of different risk factors on vocal disorders in teachers.
Material and Methods: This is a cross-sectional and descriptive-analytic study that was conducted on 73 primary and secondary male and female school teachers in Saveh in 2017 by random sampling. The researcher-made questionnaire on risk factors affecting verbal disorders with the aim of identifying risk factors and a Voice Handicap Index (VHI) questionnaire (30 items) aimed at evaluating verbal disorders and symptom questionnaire were used in this study. All of them have been shown to be valid and reliable in previous studies. Data were analyzed using t-test and chi square statistical tests by SPSS ver.24.
Results: The reliability of the researcher-made questionnaire on the risk factors affecting vocal disorders was confirmed by Cronbach’s alpha (0.736) and its validity was confirmed by the experts regarding the adequacy of the number of questions, the lack of ambiguity and the assessment of content fitness. According to our gathered data, vocal disorders were observed in 55% of the teachers. Also the results showed the rate of vocal disorders in female teachers is far higher than male teachers. Functional disturbance of vocal cords and allergy as general risk factors, teaching tools and poor air quality as environmental risk factors and inadequate vocal rest and job stress as occupational risk factors contributed to increasing vocal disorders in teachers. Among the symptom associated with verbal disorders in teachers, vocal fatigue and hoarseness were more common in comparison with other symptoms.
Conclusion: Due to the prevalence of vocal disorders in half of the teachers and the impact of general, environmental and occupational risk factors, it is necessary to identify and control the risk factors of vocal disorders in teachers. It can also be concluded that teachers can enjoy a healthy voice by considering the principles of ergonomics and occupational health.
Saeid Yazdanirad, Saba Kalantary, Farideh Golbabaei,
Volume 9, Issue 4 (12-2019)
Abstract
Introduction: Many studies, especially in recent years, have evaluated and controlled the occupational heat stress in Iran using environmental indices. However, so far, no comprehensive study has been conducted to review and classify these studies. Therefore, this study aimed to review and investigate the occupational studies performed by environmental heat stress indices in Iran.
Material and method: In the present study, the published articles from 2000 to 2016 were searched using Persian and English keywords including heat stress, heat strain, hot condition, warm condition, occupational health, thermal environment and Iran. Search of articles was performed in databases such as Web of Science, Google Scholar, PubMed, Scopus, Science Direct, SID, Magiran, Civilica, Iran Medex, Barakatkns and Irandoc. In total, 323 articles were found and 134 articles of them, based on the exclusion criteria, were selected and included in this study.
Results: Based on the results, most numbers of the studies, with 93.3 percent of the total researches related to published article, have been carried out between years of 2010 to 2016. As well as, most of studies with 61.9 percent were related to the indoor industrial environments. Most of studies were also performed in cities of Isfahan with 31.08 percent, Tehran with 16.89 percent, and Assaluyeh with 11.48 percent, respectively. As well as, WBGT index with 76 percent and the UTCI and PHS indices with 0.6 percent had the highest and lowest usage in all environments and industries, respectively. In addition, the results showed that WBGT index had most usage in industries of melting and casting with 15.7 percent, petroleum with 8.3 percent, and outdoor small occupations with 8.3 percent, respectively. Based on the results, the industries of the refinery, steel, glasswork, melting and casting, mines, and ship repairs have the highest mean values of WBGT index, respectively.
Conclusion: The results showed the need to more attention of researchers for conducting studies in outdoor environments, in different cities of Iran, on development and validation of novel heat stress indices, and on implementation and evaluation of control measures in the environments with high heat stress.
Somayeh Kamgou, Khosrou Abdi, Monire Khadem, Mahmoud Heidari, Omid Heravizadeh, Ali Daneyali, Seyed Jamaloddin Shahtaheri,
Volume 10, Issue 1 (3-2020)
Abstract
Introduction: Todays, exposure to heavy metals is happened by being produced in various environmental, industrial processes. The production of metals finally results in air pollution as well as contamination in the food chain. There are harmful effects of heavy metals such as cadmium on different organs. Therefore, this study aimed to identify and quantify cadmium in biological samples using DLLME SFOD method.
Materials and Methods: Optimization of the underlying variables played a key role in the process including sample PH, chelator, extractor and disperser solvents, ion concentration, time and rate of centrifugation and extraction time. It was done by employing central composite design (CCD) of the response surface methodology. In the process of optimization, after setting a certain pH, Specific salt concentration and ditizon added to form a complex between the metal and the chelator. A mixture of extraction and dispersant solvents added to the sample. The organic and aqueous phase separations when centrifugation and vortex carried out, the sample vial transferred to a cold ice bath and the organic solvent floated on the aqueous solvent .The organic portion containing the analyte was injected into the analyzer apparatus.
Results. The results showed that variables such as sample PH, complexing solvent, extraction solvent, centrifugation effect and extraction time play an important role in the extraction of cadmium metal ion from biological samples. The optimized method with a minimum detection limit (LOD) of 2 μg / l and a concentration factor (EF) of 50 and a relative recovery (RR) of 1.06.26 used to extract cadmium from urine samples.
Conclusion. According to the pre-test results and the optimization process, they showed that in the three factors of sample PH, salt concentration and extraction solvent volume that play a more effective role in cadmium extraction by DLLME-SFOD method.
Younes Mehrifar, Zohreh Mohebian, Hamideh Bidel,
Volume 10, Issue 2 (5-2020)
Abstract
Introduction: Risk identification and investigation is an appropriate and practical approach for the occupational health professionals. This paper aims to determine exposure to the gases and metal fumes and to perform risk analysis in three common types of welding activities in a shipbuilding industry.
Material and method: This analytical cross-sectional study was conducted in a shipbuilding industry and three types of welding were considered including SMAW, MIG and MAG welding. Sampling of Mn and Cr fumes was carried out using NIOSH 7300 standard method, and NIOSH 6014 method NO2 sampling, and also direct reading devices for CO and O3 gases. Moreover, SQCRA risk assessment method was adopted to specify the level of exposure risk.
Results: The results of risk analysis showed that among gas pollutants, O3 and NO2 in all welding processes had a very high-risk level, while among the metal pollutants; Mn metal showed a high and very high risk level in MIG and SMAW welding.
Conclusion: According to the both sampling results and risk analysis, MIG process welders are more dangerous position than other types of welding.
Bahram Samadirad , Jalil Nazari , Nahid Hasirchi , Fatemeh Baybordi ,
Volume 10, Issue 3 (8-2020)
Abstract
Introduction: Stress is one of the major problems of living in industrial societies. Job and career issues are the most important causes of stress. Job stress is one of the important factors in causing psychological injury and illness in staff and decreasing productivity in organizations. Since human resources are among the most important assets of any organization, identification of the factors causing job stress is very crucial. Therefore current study aimed to investigate the causes of occupational stress in the staff of different units of the legal medicine centers in the Northwest Provinces.
Materials and Methods: A Descriptive-analytical study was conducted was designed and conducted on 166 employees of the various units of the legal medicines centers of Tabriz, Urmia, Ardebil and Zanjan cities by census statistical method during 2016-2017. Data were collected using questionnaires consist of demographic information and Cooper job stress questionnaire. The collected data were analyzed by means of SPSS software using t-test for independent groups, ANOVA, chi square, Pearson and Spearman correlation coefficients, at the significant level of P<0.05.
Results: It was found that about 50% of the staff had moderate job stress and more than 12% had severe job stress. The comparison of mean job stress between healthy and ill individuals showed that the patients had a higher mean of job stress than healthy individuals, and this difference was statistically significant (P<0.001). The study of interference between work and life issue (family) also showed that the people whose work always interferes with their life issues had higher mean job stress than the other two groups and the difference was statistically significant (P<0.001). The result of this study also showed that there is a significant direct relationship between job stress and smoking (P<0.045), work interference and life issue (P<0.001), and a significant inverse relationship (P<0.044) with literacy. Lower incomes, shifting the place of work, the heavy work, the ignorance of the managers to work problems, dealing directly with the people, the pressures due to the completion or working against deadlines, and the lack of hope for job promotion, respectively, are the factors causing stress in the organization.
Conclusion: Compared with employees of other organizations, the legal medicines staff seemed to have a much higher prevalence of stress. The organizational authorities could help staff to improve the quality of life and reduce occupational stress by creating the correct communication, desirable support and generating the appropriate environment for job activities.
Mohsen Sadeghi Yarandi, Farideh Golbabaei, Ali Karimi, Ali Asghar Sajedian, Vahid Ahmadi,
Volume 10, Issue 3 (8-2020)
Abstract
Introduction: 1,3-Butadiene is a carcinogenic compound that can be emitted to the atmosphere from several sources like petrochemical industry. One way to determine the level of carcinogenic and health effects of respiratory exposure to pollutants in the workplace is to use risk assessment methods. The aim of this study was to comparative assessment of carcinogenic risk of respiratory exposure to 1,3-Butadiene in a petrochemical industry by the US Environmental Protection Agency and Singapore Health Department methods.
Material and method: This cross-sectional study was carried out in 2018 in a petrochemical industry that producing copolymer ABS (acrylonitrile, butadiene, styrene) in Iran. Occupational exposure to 1,3-Butadiene was measured according to the NIOSH 1024 method. Cancer risk assessment was done according to the United States Environmental Protection Agency (USEPA) and Singapore semi-quantitative methods.
Results: The average occupational exposure to 1,3-Butadiene during work shift among all participants was 560.82 ± 811.36 µg.m-3 (0.253 ± 0.367 ppm) and in all cases was below the occupational exposure limit. The average lifetime cancer risk in USEPA method in the present study was 2.71 × 10-3, Also in this method 82.2% of all exposed workers were in the definite carcinogenic risk level and 17.8% were in the probable carcinogenic risk level. The results of the Singapore health department method showed that 91.2% of all subjects were in the probable carcinogenic risk level and 8.8% were in the definite risk level.
Conclusion: The findings of the present study showed that the results of the Singapore semi quantitative risk assessment method are not in good agreement with the results of the quantitative risk assessment method proposed by the US Environmental Protection Agency. Therefore, given the high accuracy and thoroughness of the US Environmental Protection Agency's risk assessment methodology as a worldwide reference method for assessing the carcinogenic and health risk of exposure to chemicals, it is recommended to use this method instead of the Singapore method in future studies.
Mehran Pourhossein, Reza Pourbabaki, Elahe Roudi, Vahid Ahmadi Moshiran, Homa Maleck Khani, Samane Khodaverdloo,
Volume 10, Issue 4 (11-2020)
Abstract
Introduction: Errors are a byproduct of human information processing or cognitive functioning. Although everyone is disposed to an error while performing various activities, individual differences in cognitive abilities can lead to various types and rates of errors committed in similar situations. Human errors are one of the most important challenges in work environments, including health care systems, wherein such errors are abundantly occurring. Errors in the delivery of correct medications due to the resemblance in appearance and name are thus one of the cognitive errors that come about in health care systems. The main purpose of this systematic review was to evaluate evidence and approaches recently practiced to reduce medication errors caused by the use of look-alike-sound-alike (LASA) medications.
Material and Methods: The study was conducted on August 30, 2018, through searches in the databases of PubMed and Embase, all available years, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) instructions. The searches were done in the titles or abstracts of the articles using the intended terms and the Medical Subject Headings (MeSH) index in combination. These studies were selected based on the inclusion and exclusion criteria and then categorized based on the type of interventions and outputs. Finally, the data were analyzed descriptively.
Results: The research designs and methods varied widely among the studies. There were also discrepancies in the number of participants, number of tests, type of medications, and test conditions. The approaches examined in these studies were tall-man lettering, color-coding, label background variations, and use of signs and symbols. Accordingly, 11 studies had utilized tall-man lettering and the most important reported in all articles were “error rate” and “response times”. As well, a wide range of medication names had been tested. It should be noted that medication
Conclusion: errors have different dimensions, but the errors caused by the look-alike-sound-alike (LASA) medications and the effect of tall-man lettering of medication name were only investigated in the present study. Laboratory studies in this respect have shown that tall-man lettering contributes to mitigating the rate of errors, which might be due to the better legibility of labels, but evaluations in real work environments are needed to reinforce this conclusion. There is also insufficient evidence to support color-coding, as well as several other approaches such as use of signs and symbols. Because of the novelty of the studies in this field, no uniform mechanism has been so far introduced.
