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Showing 32 results for Car

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.


Fariborz Omidi, Reza Ali Fallahzadeh, Fateme Dehghani, Bahram Harati, Saied Barati Chamgordani, Vahid Gharibi,
Volume 8, Issue 3 (9-2018)
Abstract

Introduction: Workers in steel manufacturing companies are extensively exposed to the volatile organic compounds (VOCs). Considering the health effects of these compounds, the purpose of this study was to determine occupational exposure to the BTEX compounds and also evaluation of carcinogenic risk due to benzene and non- carcinogenic risk for BTEX compounds in a steel industry.

Material and Method: This cross-sectional study was conducted in the coke production unit of the steel making industry. After collecting personal samples from breathing zone of the workers and analyzing of the samples the levels of exposure to the BTEX were quantitatively determined using Gas chromatography equipped with Flame Ionization Detector (GC-FID), according to the NIOSH 1501 standard method. Then, cancer risk due to benzene and non-cancer risks from BTEX compounds were calculated using Monte-Carlo technique.

Result: The analysis of personal samples indicated that benzene concentration in energy and biochemistry and benzol refinement sections of the plant were higher than occupational exposure limits (OELs). Among the studied sections, benzol refinement as the most polluted section had the highest concentration of BTEX compounds. Non-cancer risk due to BTEX compounds in all studied sections was lower than one. Benzene cancer risk in energy and biochemistry, benzol refinement and experimental furnace sections was higher than maximum recommended value by EPA.

Conclusion: Due to the high concentration of benzene in energy and biochemistry and benzene refinement sections as well as the resultant carcinogenic risk, improvement of existing control systems and the use of modern engineering systems are necessary to control occupational exposure.


Hamideh Pirami, Zahra Zamanian, Faezeh Abbasi Balouchkhaneh, Younes Mehrifar, Fatemeh Keshizadeh,
Volume 9, Issue 2 (6-2019)
Abstract

Introduction: Carpal tunnel syndrome is followed by pushing Median nerve in the carpal tunnel of the wrist. Occupational factors such as repetitive movements of the hands and fingers and frequent wrist disturbances affect the development of this syndrome. Quality of life is a multidimensional concept including physical and mental performance. The aim of this study was to determine the prevalence of CTS and its impact on the quality of life of typists in Tehran.  
Material and Methods: This analytic descriptive cross sectional study was conducted in 1396 on 363 typists from 50 typing institutes in Tehran. Data were collected Demographic-Job Profile Questionnaire, Boston (BQ), quality of life (SF36) and Visual Analog Scale (VAS). Data were analyzed using SPSS-22 software and methods such as ANOVA and Pearson correlation tests.
Results: Among 363 participants, 215 of them were female (59.23%) and 148 were male (40.77%). The mean age was 37 ± 12.58 years. Among the typists, 51 (14.55%) had one-sided hand conflict, and 312 (85.95%) were two-sided hand conflicts. Results indicated that the prevalence of CTS symptoms among women was higher than that of men The value of Pearson correlation coefficient (range: 0.0613-0.783) showed that there was a moderate to strong correlation between the severity of symptoms scale (SSS), functional status scale (FSS) and visual analog scale (VAS) in the population under study (p< 0.05). There was also a strong and significant correlation between SSS and FSS among typists. In this study, CTS symptoms have a significant negative effect on the quality of life of the typists, but the psychological dimension quality of life is not to be affected by these symptoms.
Conclusion: Regarding the existence of CTS symptoms among typists who work most of a day with computers, there is also a statistically significant relationship between the incidence of CTS symptoms and the quality of life in this occupational group. Therefore, it is recommended that more attention should be paid to these individuals, appreciate tools be correctly designed, and further study be done.
Faranak Najarian, Farideh Golbabaei, Asghar Ghahri, Kamal Azam,
Volume 9, Issue 4 (12-2019)
Abstract

Introduction: Occupational exposure to sevoflurane as an anesthetic gases in hospitals, dental clinics and veterinary clinics has been reported in various studies. Considering the harmful effects of sevoflurane anesthetic gas on the health of exposed personnel such as reproductive, preterm delivery and fetal abnormalities and increased spontaneous abortion, it is necessary to remove them from the air of the work environment, especially the treatment centers, with inexpensive and optimal methods. This study was aimed to compare two oxide-titanium based on Activated Carbon/ Graphene Oxide Nanosheets in nano and non-nano scales.
Material and Methods: Titanium oxide particles and nanoparticles were coated on actived carbon/ Graphene Oxide Nanosheets adsorbents. The prepared sorbents were characterized by instrumental techniques such as BET, SEM, XRD, FTIR and SEM-EDS to determine their properties. After characterization, the breakthrough and adsorption capacity of sevoflurane on both adsorbents were determined using the modified wheeler equation. Finally, the software of Microsoft Office Excel 2016 and SPSS Statistic version 21 IBM were used for statistical analysis of data.
Results: the results of XRD, SEM-EDAX analysis confirmed the stabilization of titanium oxide particles and nanoparticles on the sorbents. Furthermore, the FTIR results determined the functional groups on the sorbents. The BET results also showed the coating of titanium oxide nanoparticles on composite decreased the specific surface area of adsorption in comparison to adsorption containing titanium oxide particles. The adsorption capacity of the activated carbon/ Graphene Oxide Nanosheets coated with titanium oxide nanoparticles and titanium oxide particles were 240.7 and 210.5 mg sevoflurane per gram of sorbent, respectively (p-value<0.001).
Conclusion: The results showed that composite of activated carbon/nano oxide graphene coated with titanium oxide nanoparticles has a higher adsorption capacity of sevoflurane than other composite coated with titanium oxide particle, under the same conditions. This increase can be as a result of changes in surface chemistry (increase of the functional groups) in composite.
Shiva Soury, Abdulrahman Bahrami, Saber Alizadeh, Farshid Ghorbani Shahna, Davood Nematollahi,
Volume 10, Issue 2 (5-2020)
Abstract

Introduction: In this study, Zn3(Btc)2 (metal organic framework) sorbent was introduced for sampling of Benzo[a]pyren from the air. The purpose of this study was to develop the sampling and analysis method by needle trap, with no sample preparation step.
Material and method: Zn3(Btc)2 sorbent was electrochemically synthesized and its properties were specified by FTIR, FE-SEM, and PXRD techniques. A glass chamber with a temperature of 120°C was used to make the certain concentration of Benzo[a]pyren. Factors affecting the efficiency of needle trap were evaluated and optimized using a response surface method considering a specific operating interval to achieve the highest efficiency. The performance of the proposed method was also investigated using the real samples.
Results: The highest desorption efficiency of Benzo[a]pyren was obtained when using the needle trap containing Zn3 (Btc)2 sorbent at 379°C and 9 min retention time. No significant reduction was observed in the analyte concentration by maintaining the sampler for 60 days. The limit of detection and limit of quantification of Benzo[a]pyren were obtained 0.01 and 0.03 mg/m3, respectively. The percentage of standard deviation of the measured values of Benzo[a]pyren in diesel exhaust was calculated 4.1%.
Conclusion: The highest desorption efficiency of Benzo[a]pyren was obtained when using the needle trap containing Zn3 (Btc)2 sorbent at 379°C and 9 min retention time. No significant reduction was observed in the analyte concentration by maintaining the sampler for 60 days. The limit of detection and limit of quantification of Benzo[a]pyren were obtained 0.01 and 0.03 mg/m3, respectively. The percentage of standard deviation of the measured values of Benzo[a]pyren in diesel exhaust was calculated 4.1%.

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.
Adel Mazloumi, Zeinab Kazemi, Saeed Abedzadeh, Abbas Rahimi Foroushani,
Volume 11, Issue 1 (3-2021)
Abstract

Introduction: Workers in car manufacturing industry are at risk of a high prevalence of musculoskeletal disorders, especially low back pain. Therefore, in the present study aimed to design and fabricate a portable device to evaluate the low back kinematics and to compare these variables in workers with and without low back pain (LBP) in assembly lines of an automotive industry.
Material and Methods: In the present research workers postures were assessed using OWAS direct observational method. Moreover, simultaneously, prevalence and intensity of low back pain were evaluated by Dutch Musculoskeletal Questionnaire (DMQ) and Visual Analogue Scale (VAS). After fabricating motion analysis device, a field study was conducted using the designed device among 16 volunteers to investigate low back kinematic variables in two groups of workers: LBP and non-LBP.
Results: The results showed that 62.1 percent of all working postures were high risk with corrective action levels of 3 and 4. On average, 86.1 percent of workers experienced LBP in the previous 12 months. Regarding comparison of kinematic variable in the two groups of LBP and non-LBP, workers without LBP had higher degree and duration (in second) of movements (forward flexion, lateral bending, extension, and twisting), as compared to those with LBP. However, only movement range of forward flexion in non-LBP group (mean: 64.29 and SD: 8.41), was significantly higher than those with LBP (mean: 58.97 and SD: 11.34).  
Conclusion: The device can be used as an effective tool in the ergonomics studies in the field of back pain, due to its potential to record the kinematics of the trunk, as well as its lightweight and non-interference with the task. Device’s validity was acceptable based on the comparison of the results of this device with those obtained from inclinometer.
Mohammad Ebrahimi, Mahmood Reza Azgahini, Jalil Nazari, Abdol Rasoul Safiyan,
Volume 11, Issue 2 (6-2021)
Abstract

Introduction: Carpet-weaving is one of the hard and harmful jobs, which affect the health of the workforce. Based on the previously conducted research, musculoskeletal disorders in the neck, shoulder, and lower back regions are common among carpet weavers. This study conducted to investigate the muscle activity of the shoulder and lower back regions in carpet weavers during work on traditional and ergonomic workstations by surface electromyography.
Material and Methods: 18 experienced male weavers with a mean age of 38 and mean weaving experience of 11.1 years participated in this study. Each weaver took part in two trails of 120 min. Surface EMG signal recordings were done during weaving for four muscles (bilaterally in trapezius and erector spine). The RMS and MPF values were extracted from the raw EMG signal to estimate muscle activity and fatigue.
Results: The results obtained from the 5-time intervals indicated the lowered MPF in the ergonomic workstation compared to the traditional one. The result of the mean RMS in most of the recorded times was lower in the ergonomic workstation than that in the traditional one.
Conclusion: According to the results of the study, the modified workstation was well-suited for trapezius muscles, and the traditional one had an advantage for the erector spine muscles.
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).
Vida Rezaei- Hachesu, Shadi Naderyan Fe’li, Khadije Maajani, Rajabali Hokmabadi, Farideh Golbabaei,
Volume 12, Issue 1 (3-2022)
Abstract

Introduction: Covid-19 pandemic has imposed a significant effect on mental health of the health care workers. The present systematic review and meta-analysis aimed at determining the pooled prevalence of anxiety and depression among Iranian health care workers during the Covid-19 pandemic.
Material and Methods: To conduct this systematic review and meta-analysis, Web of Science, Scopus, Medline (PubMed), Embase, SID, Magiran databases and Google Scholar search engine were investigated to find studies over the prevalence of anxiety and depression among health care workers during the Covid-19 pandemic from December 2019 to June 10, 2021. Quality of the primary studies was assessed using the Newcastle-Ottawa tool and the random effects model was applied to estimate the pooled prevalence. Furthermore, χ2 test and I2 index were used to evaluate the degree of heterogeneity among the studies. The pooled prevalence of anxiety and depression in different subgroups was reported based on the severity of anxiety and depression, assessment tools, and staff jobs.
Results: Of 488 articles obtained as a result of the initial search, 10 related studies were identified and entered into the systematic review and meta-analysis. The pooled prevalence of anxiety was 42% (95% CI: 25-75) and the pooled prevalence of depression was 35% (95% CI: 19-55). The pooled prevalence of anxiety was 54% (95% CI: 39-70) in the occupational group of nurses and 29% (95% CI: 17-44) among all health care workers. The pooled prevalence of depression was 46% (95% CI: 30 to 63) and 17% (95% CI: 10 to 26) among nurses and all health workers, respectively.
Conclusion: According to the findings, a high prevalence of anxiety and depression was observed among the health care workers of Iran during the Covid-19 epidemic. The authorities are required to plan for preventive and therapeutic interventions to reduce the psychological burden of the epidemic.
Zahra Alaei, Roohollah Ghasemi, Mohammad Reza Pourmand, Ali Karimi, Ensieh Masoorian, Farideh Golbabaei,
Volume 12, Issue 2 (6-2022)
Abstract

Introduction: Volatile organic compounds are the most common pollutants in the air, and among them, toluene is the most common form, which is toxic resulting in liver and kidneys damages. Regarding the fact that this compound is widely used in various chemical industries, implementing an efficient method for controlling its concentration is of great importance. The comparative survey of the capability of virgin activated carbon with the one immobilized by pseudomonas putida PTCC, and also the performance of the biofiltration system involving pseudomonas putida bacteria immobilized on activated carbon for the adsorption and degradation of toluene from the air as well as regenerating the activated carbon were aimed in the present study.
Material and Methods: The microbial growth process was initiated by incubation of pre-culture in a rotary shaker, at 150rpm overnight. After 4 days, the strain pseudomonas putida, PTCC No: 1694 was immobilized on a certain amount of activated carbon. Subsequently, an airstream containing toluene was introduced into the biofilter, and the inlet and outlet concentrations of toluene were measured.
Results: The obtained results illustrated that the increase in the volume of the media and decrease in the gas flow rate significantly enhances efficiency. The great performance of the biofilter was confirmed by the high efficiency of the immobilized activated carbon which exhibited 89% yield during 14 hours. On the second cycle, the biofiltration system was able to adsorb toluene at an efficiency of 81%, while the virgin activated carbon exhibited far less efficiency with the value of 28%.
Conclusion: The provided results demonstrated the feasibility and reusability of the biofilter system for toluene removal. The proposed technique also extends the activated carbon’s capacity, which could be a potential solution to re-use the activated carbon in industrial applications.

Delnia Jahani, Faranak Jabbarzadeh Tabrizi, Abbas Dadashzadeh, Parvin Sarbakhsh, Mina Hosseinzadeh,
Volume 12, Issue 3 (9-2022)
Abstract

Introduction: Nurses of the emergency department experience stressful events that affect their mental health and reduce the quality of their work life. Career adaptability is considered a personal capability that enables employees to adapt to changes and avoid the negative consequences of job mismatch. This study was conducted to study career adaptability and its correlation with the quality of work life in the emergency department.
Material and Methods: This descriptive-correlational study was conducted on 104 nurses in the emergency department of teaching–therapeutic hospitals in Tabriz who were selected using random stratified sampling. Data was collected using a demographic checklist, the Career Adapt-Abilities Scale (CAAS) by Savickas, and the Quality of Nursing Work Life (QNWL) scale by Brooks & Anderson. Data were analyzed in SPSS using descriptive statistics (frequency, mean and standard deviation) and inferential statistics (independent t-test, one-way analysis of variance, Pearson’s correlation coefficient, and linear regression analysis).
Results: The total scores of career adaptability and the quality of nursing work life were 88.55±25.01 from the achievable range of 24-120 and 141.15±22.56 from the achievable range of 42-252, respectively, which were moderate. In this study, 85.6% of nurses enjoyed a moderate quality of work life. Furthermore, the results of Pearson’s correlation indicated a significant positive correlation between career adaptability and scopes with the quality of work life score (p=0.05). Regression analysis results indicated that career adaptability significantly predicts the quality of nursing work life (p=0.000).
Conclusion: In this study, nurses experienced moderate career adaptability and quality of work life. Given the above factors, and considering adaptability as a variable predicting quality of work life, it is suggested to take measures to increase career adaptability in nurses through training or consulting interventions to improve the quality of nursing work life.
Rajabali Hokmabadi, Esmaeil Zarei, Ali Karimi,
Volume 13, Issue 2 (6-2023)
Abstract

Introduction: Reliability is always of particular importance in system design and planning; thus, improving reliability is among the approaches for achieving a safe system. Simulation methods are widely used in system reliability assessment. Therefore, this study aims to assess the reliability of the City Gate Gas Station (CGS) using Monte Carlo Simulation (MCS).
Material and Methods: This descriptive and analytical study was conducted in one of the CGSs of North Khorasan Province in 2021. The CGS process was carefully examined and its block diagram was plotted. Then, failure time data of CGS equipment were collected over 11 years and time between failures of subsystems was calculated. The failure probability distribution function of subsystems was determined using Easy Fit software and Kolmogorov-Smirnov test. Moreover, subsystems’ reliability was estimated by MCS. Finally, station reliability was calculated considering the series-parallel structure of the CGS.
Results: The results revealed that the failure probability density distribution function of CGS subsystems was based on gamma and normal functions. The reliabilities of filtration, heater, pressure reduction system, and odorize were calculated as 0.97, 0.987, 0.98, and 0.992 respectively, and their failure rates were 0.000003477, 0.0000014937, 0.0000023062, and 0.0000009169 failures per hour respectively. The station reliability was calculated as 0.93.
Conclusion: The failure probability distribution function and reliability assessment of subsystems were determined by data modeling and MCS respectively. Filtration and pressure reduction systems had the highest failure rate and required a proper maintenance program.
Zeinab Rostami, Mohammad Reza Abedi, Parisa Nilforooshan,
Volume 13, Issue 4 (12-2023)
Abstract

Introduction: Due to the lack of an instrument for measuring the career issues of those with bipolar disorder, the present study was conducted to develop and examine the psychometric characteristics of the Career Issues Inventory for Persons with Bipolar Disorder (CII-BD).
Material and Methods: To check the diagnostic validity, via purposive sampling and interviews by a psychiatrist, 108 people were selected from two sample groups (53 normal people and 55 participants with bipolar disorder). The items were extracted from three sources including scientific articles related to the career issues of bipolar people, interviews with individuals with bipolar disorder, and interviews with experts using the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) systematic qualitative method. Finally, the items of the CII-BD were reduced to 81 questions. Content, construct, and convergent validity plus factor analysis of CII-BD were also examined. The reliability of CII-BD was evaluated by internal consistency and test-retest method with seven weeks intervals after the initial implementation of the CII-BD.
Results: The convergent validity of the sum score of CII-BD with the sum score of the symptom inventory of people with bipolar disorder among the sample of normal people and the sample of persons with bipolar disorder was (r=0.79, P<0.01, N=53) and (r=0.78, P<0.0001, N=53) respectively. In construct validity examination, nine subscales were extracted using the factor analysis method with varimax rotation, which included communication problems, poor work performance, insecurity, grandiosity, unreliability, change-seeking, vulnerability, lack of boundaries, and lack of self-control towards the opposite sex. In the reliability analysis, Cronbach’s alpha coefficient was 0.96 (N=55, participants with bipolar disorder) and 0.86 (N=53, normal people), respectively, P<0.05, showing the high internal consistency of CII-BD. The test-retest correlation coefficient of the sum scores of the CII-BD was r = 0.91, P < 0.01, which indicated the credible stability of the CII-BD.
Conclusion: The CII-BD is a valid and reliable instrument to measure the specific career issues of bipolar persons and their early vocational rehabilitation. It is suggested that future research should focus on choosing a job and job placement for bipolar disorder persons.
Pourya Ahmadi Jalaldehi, Jila Yavarian, Farideh Golbabaei, Saba Kalantary, Abbas Rahimi Foroushani, Hossein Abbaslou,
Volume 13, Issue 4 (12-2023)
Abstract

Introduction: The COVID-19 pandemic has been a significant global health challenge. Primary care services, such as screening health centers, were crucial in identifying infected individuals. However, these centers were often crowded and posed a high risk to staff and non-COVID-19 patients. This study aims to assess the risk of airborne transmission of SARS-CoV-2 in such settings through simulation.
Material and Methods: In this study, waiting and sampling rooms of a COVID-19 healthcare center were simulated using different scenarios. Then, the Quanta emission rate was estimated using the viral load in the sputum of infected individuals. Finally, the airborne transmission risk of SARS-CoV-2 was determined using the Wells-Riley method for scenarios of wearing and without masks.
Results: The study showed that the Quanta emission rate in an unmodulated speaking activity was higher than other expiratory activities in both units (p <0.001). Also, the total amount of Quanta was slightly higher in the sampling room than in the waiting room, which was not statistically significant. On the other hand, the calculation of transmission risk showed that the probability of airborne virus transmission in the sampling room was higher (about 2 to 8%). In addition, wearing masks reduced the possibility of airborne transmission of the virus significantly (77 to 81%).
Conclusion: This study shows that the level of risk in the sampling and waiting rooms is moderate. Masks also significantly reduce the possibility of airborne transmission of SARS-CoV-2. Taking appropriate health and safety measures such as avoiding crowds, wearing masks, whispering, and monitoring social distancing can reduce the plausibility of airborne transmission of the SARS-CoV-2 virus.
 
Mahdi Alinia Ahandani, Saba Kalantary, Monireh Khadem, Fatemeh Jafari, Kamal Azam, Farideh Golbabaei,
Volume 13, Issue 4 (12-2023)
Abstract

Introduction: VOCs are harmful air pollutants that must be detected, monitored and eliminated. Adsorber tubes are standard tools for this task, specifically activated carbon tubes with high adsorption and selectivity. This research aims to compare the structural and functional characteristics of domestically produced activated carbon tubes with the conventional commercial ones for sampling toluene, a volatile organic compound.
Material and Methods: The characteristics of each adsorbent, such as structure, morphology, porosity, and element composition, were examined by SEM photography, BET testing, and EDAX analysis. The central composite design (CCD) method was employed to investigate the adsorption properties of the adsorbents. The input concentration and readsorption time of the samples were the variables considered in this study. Additionally, a field phase of personal air sampling was performed to evaluate the effectiveness of adsorbent tubes.
Results: SEM and BET analyses indicated that the porous structure of domestic activated carbon was comparable to the model produced by SKC. EDAX analysis detected a minor impurity (1%) in the domestic activated carbon adsorbent. The adsorption performance was significantly influenced by the variations in readsorption time and pollutant input concentration. The accuracy and precision of the performance of the domestic adsorbent tube were obtained as 90.77% and 91.76%. The field phase results demonstrated that the amount of pollutant adsorbed in the SKC-activated charcoal adsorber did not differ significantly during 0 to 30 days. However, the domestic adsorber showed a significant difference in the same period. The overall performance of the two adsorbers did not exhibit a significant difference between 0 and 30 days.
Conclusion: Despite minor structural differences, the adsorption efficiency of toluene by domestic adsorbent tubes in sampling high concentrations is very similar to its commercial type. However, it is not recommended for use in low-concentration environments (10 ppm and less).
Mojtaba Zokaei, Milad Abbasi, Mohsen Vahidnia, Mohamad Zarie, Fardin Zndsalimi, Mohsen Falahati,
Volume 14, Issue 3 (10-2024)
Abstract

Introduction: Nowadays, the statistics prove that the underground construction projects in the country are increasing, as well as the number of accidents arising from the unsafe condition of these projects. The purpose of this study was to create a framework of safety and health risk management in the construction phase of the Tehran Metro Line 7 tunnel, using IoT technology.
Material and Methods: In the first stage, the national safety and health standards, laws and requirements related to the mentioned hazards were collected. In the second stage, the criteria and permissible limits of exposure to occupational hazards were determined. Next, sensors with optical, auditory, gas detection, and visual capabilities connected to the network were examined, and computer programming and comparing sensor information with the specified standards were carried out. Finally, intelligent warning and control systems related to the determined hazards were proposed.
Results: In this study, a combined model of risk management utilizing IoT for controlling and monitoring safety and health hazards such as sound, light, explosive and toxic gases was proposed. According to the model, sensors for detecting the mentioned hazards were determined and coded based on the permissible limit of each of the harmful factors.
Conclusion: This study has shown that by employing specialized IT and safety knowledge and utilizing relevant software and hardware, the concept of the Internet of Things can be utilized in precise monitoring of the concentration levels of flammable and toxic gases, as well as monitoring of physical agents such as noise and light in various workplace, such as metro tunnel construction sites.
Mahdi Jafari Nodoushan, Amir Houshang Mehrparvar, Mohammad Ali Ghoveh Nodoushan, Reza Jafari Nodoushan, Ali Karimi,
Volume 15, Issue 2 (7-2025)
Abstract

Introduction: Safety in healthcare facilities is critically important for the health and well-being of employees, patients, and organizational effectiveness. In recent years, various studies have examined the relationship between leadership styles or approaches and safety performance as one of the indicators of safety promotion. The present systematic review examines the relationship between different leadership styles and the safety performance of employees in healthcare facilities to provide a better understanding of the positive or negative effects of leadership on safety and to suggest strategies for improving safety performance in healthcare facilities. 
Material and Methods: A search was conducted in Scopus, PubMed, and Web of Science (ISI) databases. Keywords related to leadership, safety performance, and healthcare employees were used. Studies published up to the end of 2024 were identified and reviewed in accordance with PRISMA guidelines.
Results: Nineteen relevant papers were selected and included in the study. During the review of studies, eleven leadership styles or approaches were identified in relation to safety performance in various healthcare facilities. These included transformational leadership, leader-member exchange leadership, leader safety priority communication and feedback, ethical leadership, empowering leadership, inconsistent and destructive leadership, transactional leadership, task-oriented leadership, authentic leadership, safety leadership, and servant leadership. All leadership styles except for inconsistent and destructive leadership had a direct or indirect positive effect on safety performance. Also, the largest number of studies (n=4) focused on transformational leadership style and leader-member exchange leadership.   
Conclusion: The selection of appropriate leadership styles can contribute to enhanced safety, a reduction in occupational incidents, and improving service quality in healthcare settings. The findings of this study highlight the importance of developing effective leadership styles and strengthening appropriate managerial approaches to improve safety in healthcare facilities. 
Rohollah Fallah Madvari, Hamideh Bidel, Hadis Ghajari, Zahra Jegari, Fatema Babaee, Milad Abbasi,
Volume 15, Issue 3 (10-2025)
Abstract

Introduction: Workplace noise is one of the main sources of health problems. Noise can have many direct and indirect effects that threaten human health in various ways. The aim of this study was to investigate the effect of noise annoyance on anxiety among workers.
Material and Methods: This study included 60 workers from a carton manufacturing company, who were divided into two groups based on noise exposure: exposure (noise level more than 85 dB) and control (noise level less than 85 dB). Noise exposure of the individuals at the workplace was measured in accordance with ISO 9612:2009 standard and using a TES-1354 dosimeter. Anxiety levels were assessed using the Spielberger Anxiety Inventory (STAI), and noise annoyance was measured using a 100-point visual analog scale. Statistical analysis was performed using STATA statistical software. 
Results: The mean age and work experience of the study subjects were 35.78 and 10.78 years, respectively. The results indicated a statistically significant difference (P-value < 0.05) in the mean noise annoyance scores between the groups. The mean noise annoyance score in the exposed group was significantly higher (88.03) than in the non-exposed group (47.6). The average anxiety scores in the exposure and control groups were 106.81 and 101.6, respectively. In addition, regression analysis showed that each unit increase in noise annoyance level resulted in a 1.08-fold increase in anxiety in the exposed group.
Conclusion: Noise annoyance is often the most common psychological response to noise exposure and can be a predictor of many mental disorders or illnesses, including anxiety. Therefore, it is important to implement control measures to reduce noise exposure in the workplace.
Ali Karimi, Esmaeil Zarei, Rajabali Hokmabadi,
Volume 15, Issue 4 (12-2025)
Abstract

Introduction: A gas pressure reduction station is an important facility in gas transmission systems. These systems consist of various sections, the reliability of each section affecting the station’s overall reliability. Therefore, this study aimed to assess the reliability of station sections using Markov chain Monte Carlo (MCMC) and the continuous-time Markov chain (CTMC) method.
Material and Methods: Equipment failure and repair rates were simulated using the MCMC method in WinBUGS14. Then, based on the failure and repair rates, the station reliability was evaluated using the CTMC. The results of the equipment failure rate simulation were validated using two criteria: MC Error and the Goleman-Rubin test. Also, the results of station reliability evaluation were validated using Reality Check and Partial Benchmark Exercise methods.
Results: Failures in the filtration and pressure reduction sections were more frequent than in other sections of the station. Therefore, these sections were considered the most critical sections in the reliability assessment. The posterior standard error was less than 0.01, indicating good convergence of the data for the parameter posterior distribution. The results of the Goleman-Rabin test showed values less than 1.2, indicating proper convergence of the chains. For all sections and stations, a systematic approach was determined using the Markov model. The results showed a strong correlation between the CTMC and the block diagram method (R2=0.9499).
Conclusion: The proposed approach combines failures of system components and can display multiple failures. It also accounts for time factors in its calculations and minimizes subjective expert evaluations.

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