Showing 10 results for Alizadeh
F. Alizadeh, M. H. Taghdisi, S. M. R. Mirilavasani,
Volume 4, Issue 4 (1-2015)
Abstract
Introduction: The purpose of this study was to compare MORT and Tripod Beta methods, using a hierarchical model, in order to choose the best technique to analyze an event in an organization.
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Material and Method: In this study, a critical event was selected and the causes of the event were identified, employing MORT and Tripod Beta capabilities. Following the identification of the event causes, the aforementioned techniques were weighted and compared considering selected criteria and AHP hierarchical method.
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Result: Relative weights of the selected criteria were calculated. The ability to identify the event causes with the weight of 0.315 had the greatest weight. The event analysis cost (0.24), required time to analyze the event (0.146), technical experts (0.125), training for implementation (0.24), and availability of the analytical software (0.07) had obtained the subsequent weights, respectively.
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Conclusion: Analytic hierarchy process is an efficient and practical method to prioritize the choices considering the study objectives and criteria. As scientific method, Analytic hierarchy process helps the experts in decision-making. Considering the selected criteria, findings in this study showed that Tripod Beta technique (with a weight of 0.563) is superior to MORT technique (with a weight of 0.437).
Mohammad Kamaei, Seyed Shams Aldin Alizadeh, Abdolrahman Keshvari, Zeynab Kheyrkhah, Parisa Moshashaei,
Volume 6, Issue 2 (6-2016)
Abstract
Introduction: Although human industrial activities are as a part of efforts to achieve greater prosperity, the risks related to these activities are also expanding. Hazard identification and risk assessment in the oil and gas industries are essential to reduce the frequency and severity of accidents and minimize damage to people and property before their occurrence. The aim of this study was to evaluate the liquefied and pressurized petroleum gas spherical tanks in a refinery and assessing the risks of Boiling Liquid Expanding Vapor Explosion (BLEVE) phenomenon.
Material and Method: In this study, the risks of BLEVE phenomenon were assessed, using the Bowtie method. The consequences of explosion wave phenomenon and the resulting wave quantity and its impacts on the neighboring machineries and equipment were analyzed. PHAST software version 6.54 has been used for modeling the BLEVE phenomenon.
Result: In this evaluation, generally five causes and two consequences were identified for BLEVE phenomenon. In order to reduce its consequences, forty-three controlling measures were introduced to prevent the BLEVE phenomenon and the impacts of 31 control measures were identified. According to the conducted analysis, it was found that the spherical tank blast wave caused by LPG can lead to explosion of close located tanks which can create a chain of explosions.
Conclusion: The results of modeling and risk assessment can be used to identify the BLEVE phenomenon causes and its effects on nearby people and equipment. Based on these results, preventive controlling measures can be implemented and also be determined by adopting proper design and layout, margin of safety for personnel, equipment and accessories.
Parisa Moshashaei, Jalil Nazari, Seyed Shamseddin Alizadeh,
Volume 7, Issue 3 (9-2017)
Abstract
Introduction: Population growth and urban fast development caused increase production of all kinds of solid waste. And, street sweepers are exposed to a variety of risks and toxins by nature of their job for actual and potential. The aim of this study was to identify and to assess the risk factors of accidents and diseases threatening the health and lives of street sweepers in Tabriz city, Iran, and to propose practical solutions to control and remove them in order to promote health and safety and better efficiency.
Material and Method: This study is a descriptive-analytical type, which was conducted over a period of three months in 1393 among 150 street sweepers working in five city areas (areas 2, 5, 6, 7 and 9) of Tabriz. Data was collected through customized questionnaire. Content validity of the questionnaire was performed in the form of quality using a panel of experts and reliability through Cronbach’s alpha. Data after collecting were analyzed by SPSS-16software.
Result: The results showed that 48/7% of people have experienced at least one incident in the past two years. Records of disease showed that back pain with 20/7% and then skin problems whit 7/10% whit highest prevalence and kidney/bladder disease and thyroid whit 0/7% had lowest incidence. Musculoskeletal disorders symptoms percent have, respectively, in the hands, waist, legs highest and in elbow and knee least amount. Research findings showed that 50/70% of the study population, with a mean score of 168/82 have poor health and safety conditions, 21/71% of people have moderate condition and 81/26% of people have unfavorable condition. Among the components of health and safety respectively, components of clothes and other personal protective equipment and psychological problems with a high percentage of 80 percent, one of the most undesirable components of safety and health and components of periodic medical examinations and safety and health training programs were desirable.
Conclusion: The results showed that more than half of street sweepers (70/50%) had undesirable health and safety condition. Shortages or lack of use of personal protective equipment and psychological problems among these workers was evident more than other issues and need for substantial measures in this regard
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.
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%.
Zahra Alizadeh, Mostafa Pouyakian, Koorosh Etemad,
Volume 12, Issue 2 (6-2022)
Abstract
Introduction: Human beings are inherently different and this fact can affect his/her behavior in work environments. The aim of this study was to examine the individual differences of employees (personality traits, biological and demographic factors) as a predictor of unsafe behaviors in a turbine manufacturing company.
Material and Methods: In this cross-sectional study, safety behavior sampling technique, NEO-FFI questionnaire, demographic information questionnaire, BMI and cell type method were used to determine unsafe behaviors, personality traits, demographic variables, body mass index and blood group system, respectively. The statistical sample of the study was 260 employees of a turbine manufacturing industry. The SPSS software version 20 was used to analyze the data.
Results: The results showed that 44.5% of employees’ behaviors were unsafe. There was a significant relationship between the occurrence of unsafe behaviors with smoking, BMI, blood type and neuroticism and agreeableness dimensions measured by NEO-FFI (p < 0.05). BMI was the most important predictorof unsafe behaviors in the present study.
Conclusion: Due to the role of individual differences in people’s tendency to unsafe behaviors, the results of this study can be considered in job design, screening of personnel according to their individual differences, and perform better interventions to prevent accidents at work.
Alireza Shaghaghi, Zeinab Kazemi, Ali Sharifnead, Ehsan Garosi, Maryam Mohammadalizadeh, Seyed Hossein Mahdavi, Mohammad Sadegh Ghasemi,
Volume 13, Issue 2 (6-2023)
Abstract
Introduction: In many occupations, users must sit for prolonged periods during their job activities. Prolonged sitting is associated with fatigue, leading to postural changes that can increase spinal loads. Despite the importance of this topic in terms of the extent of prolonged sitting and its subsequent adverse consequences, little attention has been given to this occupational activity. Hence, this study investigates changes in neck, trunk, and muscle activities and fatigue levels in prolonged sitting computer tasks.
Material and Methods: Twenty healthy subjects (gender-balanced) from the student community with at least five years of experience in computer work aged between 20-30 years were asked to randomly perform three types of computer tasks for 90 minutes (each task for 30 minutes). Electromyographic (EMG) activities of right and left cervical (ESCR and ESCL), thoracic (ESTR and ESTL), and lumbar (ESLR and ESLL) erector spine and upper trapezius (UTR and UTL) muscles were continuously recorded. Root mean square (RMS) and median frequency were extracted as EMG metrics. Subjects also rated their perceived discomfort using a Visual Analogue Scale (VAS). The effect of time, gender, and their interaction on muscle EMG activities, fatigue, and discomfort were explored.
Results: Time had a statistically significant effect on UTR, ESCR, and ESTR muscle activities. UTL and ESCR muscle activities significantly differed between male and female subjects. Further, the findings confirmed the interactive effect of time and gender on ESTR muscle activity. UTR, ESCR, ESCL, ESTL, and ESLL muscles’ fatigue index changed statistically over time.
Conclusion: The findings confirmed neck and trunk muscles’ fatigue by increasing muscular activity and reducing frequency contents over time, per the subjective rating of discomfort.
Maryam Mohammadalizadeh, Zeinab Kazemi, Ehsan Garosi, Ahmadreza Keihani, Alireza Shaghaghi, Mohammad Sadegh Ghasemi,
Volume 13, Issue 3 (9-2023)
Abstract
Introduction: Prolonged sitting postures are among the risk factors for musculoskeletal disorders in occupational settings, leading to increased musculoskeletal discomfort in various body regions. This discomfort can negatively impact individuals’ health and impose high costs on society in terms of work absences, early disabilities, and reduced productivity. The purpose of this study is to investigate the effect of stretching exercises on the level of discomfort, muscle activity, and muscle fatigue in the neck and trunk region during prolonged sitting tasks.
Material and Methods: This experimental study was conducted among 20 healthy male and female participants under two test conditions: control and intervention. In the control condition, participants performed cognitive tasks (watching videos, typing, text editing, and nback cognitive test) without any intervention. In the intervention condition, participants performed stretching exercises before each task. The Visual Analogue Scale was used to assess perceived discomfort. Also, muscle fatigue was evaluated using an electromyography (EMG) device and RMS and MPF measures.
Results: Discomfort in hands and arms (p-value=0.04) and lower back (p-value=0.03) during video-watching was higher in the control condition than in the intervention. Regarding muscle activity, the activity of the right cervical erector spinae during the video-watching task was lower in the control condition than in the intervention. In the n-back cognitive test and text editing, the right lumbar erector spinae muscle activity was significantly higher in the control condition than in the stretching exercises intervention. Regarding the left cervical erector spinae, a significant difference was observed between fatigue in control and intervention conditions during the video-watching task. Also, right thoracic erector spinae fatigue in text editing was higher in the control condition than in the exercise intervention; however, for the n-back test, the level of fatigue was lower in the control condition compared to the intervention.
Conclusion: The perceived discomfort in seated computer tasks is generally lower in the exercise intervention compared to the control condition. The stretching exercises used in this study improved muscle activity and reduced fatigue in some of the trunk muscles, although the effects of the exercises depend on the type of task. Overall, muscle fatigue in two cognitive tasks, text editing and n-back, was more affected by stretching exercises than other tasks.
Mohammad Javad Sheikhmozafari, Fatemeh Sadat Mirnajafi Zadeh, Neda Sasani Nasab, Parsa Mohammad Alizadeh, Jamal Biganeh, Seyed Abolfazl Zakerian,
Volume 13, Issue 4 (12-2023)
Abstract
Introduction: Work-related musculoskeletal disorders (WMSDs) are a prevalent occupational health concern, influenced by both physical and psychosocial factors. Valid questionnaires offer a cost-effective and efficient means of evaluating WMSDs. This study aimed to validate the Persian version of the MDRF questionnaire, assess its applicability in Iran, and investigate the prevalence of WMSDs among employees in an automotive industry.
Material and Methods: This descriptive cross-sectional study was conducted among 100 employees (50 production line workers and 50 office workers) in Kerman province. The linguistic validity of the questionnaire and its translation were ensured using the Backward-Forward method. Content validity was assessed through CVI and CVR indexes. To evaluate the questionnaire’s reliability and agreement, Cronbach’s alpha and ICC were employed. User responses from the first and second series of the questionnaires were validated using Kappa and Spearman’s tests.
Results: Results indicated high reliability which was achieved by Cronbach’s alpha and ICC values of 0.960 and 0.925, respectively. The questionnaire’s validity was acceptable based on CVR and CVI tests. The prevalence of WMSDs was the highest in the lower back for both production line and office workers over the past year. The job satisfaction factor exhibited the highest risk level among the questionnaire’s four subgroups. Approximately 85% of participants were classified as having a high or very high-risk level, reflecting concerning conditions among the employees. The prevalence of WMSDs in different body parts significantly correlated with all physical and psychosocial stress factors.
Conclusion: This research highlights the influence of diverse physical and psychosocial risk factors on the occurrence of WMSDs among both occupational workers and office employees. Also, the MDRF questionnaire, whose high applicability in assessing the WMSDs risk factors was proven in this study, is an effective tool for prioritizing, planning, and executing educational and preventive measures within the workforce community to mitigate and prevent WMSDs.
Elahe Chubineh, Saber Azami Aghdash, Ali Esmaili, Seyed Shamseddin Alizadeh,
Volume 14, Issue 2 (6-2024)
Abstract
Introduction: For years, chemical process industries have reported the unexpected release of highly hazardous liquids and gases. A disaster could not be avoided when these materials were not adequately controlled. The issue of Process Safety Management (PSM) is still being discussed in developing and developed countries. PSM was established to manage the risks of a company’s personnel, properties, products, environment, and credit risks. This study aimed to review the challenges and achievements of PSM implementation and provide recommendations for improvement.
Material and Methods: A collection of scholarly articles published from 2000 to 2023, such as Science Direct, WOS, PubMed, and Scopus, was chosen through a systematic, meticulous review. After thoroughly examining these abstracts, titles, and complete contexts, 49 articles were finally selected for inclusion in the study and classified based on different criteria, such as publication year, authors, achievements, and challenges.
Results: PSM in the United States has been chiefly studied due to the high number of chemical process industries and its presence in the form of OSHA legislation in this country. The areas of operations, audits, and resources have the most challenges in implementing PSM. On the other hand, reducing the severity of incidents in chemical processes and increasing productivity are considered the most significant achievements of PSM implementation.
Conclusion: PSM as an interdisciplinary field has improved and become more effective over the years.. However, incidents still exist, and the number can increase, considering the growth of industries’ chemical processes. Therefore, a deep look at the issues of risk-based regulations, competency, operational excellence, and learning from incidents is necessary to achieve excellence in PSM.
