Showing 3 results for Ramezanifar
Soleiman Ramezanifar, Ehsan Ramezanifar, Elahe Khadiv, Ali Salehi Sahlabadi, Davoud Eskandari, Mahshid Namdari,
Volume 12, Issue 3 (9-2022)
Abstract
Introduction: Human error can occur in many work environments, especially in control rooms. Due to the vital role of the central railway traffic control room in guiding and controlling all types of trains along the railway network, any error in this control room can lead to a catastrophic accident. This study aims to identify and assess human error in the central control room of railway traffic using the HEART technique.
Material and Methods: This descriptive cross-sectional study was performed in 2021. In this research, tasks and sub-tasks were identified using the hierarchical task analysis (HTA) method. Then, the probability of human error was assessed using the HEART technique.
Results: Based on the results of the HTA method, 67 main tasks, and 149 sub-tasks were identified. The study results on the probability of human error using the HEART technique showed that the three main tasks of the traffic expert (distribution of types of diesel, establishing the freight priority, and planning the movement of trains) had the highest probability of error. In addition, the most critical factors influencing human error were “evidence of illness among employees”, “sleep disorder”, “inexperience”, “unfamiliarity”, and “stress”.
Conclusion: The results of this study indicated that the central railway traffic control room employees are prone to errors, and if these staff make errors, irreparable accidents will occur. To reduce the probability of error of these employees, measures should be considered, such as using regular and appropriate shifts, the use of skilled and competent people, and so on.
Younes Mehrifar, Soleiman Ramezanifar, Sona Beyrami, Sara Talebolhagh, Ehsan Ramezanifar, Pardis Amiri, Mostafa Pouyakian,
Volume 12, Issue 4 (12-2022)
Abstract
Introduction: Due to occupational accidents, many costs are annually lost from the countries’ Gross Domestic Product (GDP). Estimating these costs can be essential for optimal investments and establishing appropriate policies in many countries, such as Iran. The present study aimed to review the studies conducted on the safety economics and the costs of accidents in Iran from 2000 to 2021.
Material and Methods: The reliable databases “Web of Science”, “Embase”, “IranDoc”, “SID”, “Magiran”, “Google Scholar”, “PubMed” and “Scopus” were used to conduct this research. Articles in these databases were searched and extracted by searching for keywords such as “accident”, “cost of accidents”, “occupational accidents” and “Iran” in Persian and English from 2000 to 2021.
Results: Among the 66 identified articles, 19 were selected as final articles, of which 11 studies were carried out in the transportation industry and eight in other industries. Among these studies, nine studies only examined and stated the total costs, and six studies separately examined and stated the direct, indirect, and total costs. Four other studies also investigated and expressed the costs caused by accidents in other ways. Most notably, in three studies, the number of direct costs is higher than indirect costs. Similarly, only six studies estimated the damage to the GDP, ranging from 0.03% to 6.46% of the GDP.
Conclusion: The results of the review of studies showed that occupational accidents cause the loss of a significant part of Iran’s GDP. It is recommended to carry out further studies on the relationship between investment in the safety sector and reducing the costs of accidents concerning the grouping of jobs, mainly in the process, service, and production industries, to prevent wasting such heavy costs.
Ehsan Ramezanifar, Kamran Gholamizadeh, Iraj Mohammadfam, Mostafa Mirzaei Aliabadi,
Volume 13, Issue 1 (3-2023)
Abstract
Introduction: Risk assessment is a scale for predicting reliability and can manage interactions between components and process variables. Moreover, the reliability of one component or barrier affects the overall risk of the system. Being one of the most critical safety barriers of the storage tank, the failures of Fixed Foam Systems (FFS) on demand can result in severe consequences. FFS, is of grave importance in decreasing the risks associated with fires and damages.
Material and Methods: This study aims to determine the probability of root causes related to FFS failure through Fuzzy Fault Tree Analysis (FFTA) to estimate system reliability. In conventional fault tree analysis, accurate data is usually used to assess the failure probability of basic events. Therefore, the introduced approaches were employed to quantify failure probabilities and uncertainty handling. Finally, system reliability was estimated according to the failure probability of the top event.
Results: The findings showed that 13 baseline events involved FFS performance. According to the results, failures of cable path and detection system (or resistance temperature detectors), set the activation switch (multi-position) incorrectly, and foam makers not continuously running are the three most critical basic events influencing the reliability of fixed foam systems. In addition, this paper estimated the system reliability at 0.8470.
Conclusion: The results showed that the FFTA could be used in matters such as reliability evaluation failure and risk assessment using experts’ judgment. This paper can also show the adaptation of the fuzzy approach to assess the failure probability of the basic event in the fault tree analysis (FTA).
