Journal of Health and Safety at Work

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Introduction: The formation and evolution of culture in organizations are related to the learning experiences of their members over time. In this regard, the present study was conducted to empirically investigate the correlation relationship between the Learning Organization (LO) and safety culture concepts in Iran’s nuclear and radiological industries.
Material and Methods: A theoretical model concerning the connections between seven facets of LO and safety culture was proposed. It was then empirically tested with a structural equation modeling PLS analysis of a survey data set of 388 observations, collected from the radiation workers of 45 organizations in 4 Iranian industrial groups i.e. medical radiation, industrial radiography, nuclear installations, and radiological installations. Yang’s DLOQ questionnaire in 2004 and IAEA’s SCPQ-LH questionnaire in 2017 were used to measure LO and safety culture, respectively.
Results: According to the findings of this study, being a LO could explain 52% of the variance in safety culture. Besides, it was observed that the strength of this relationship between four different subpopulations of Iran’s radiological and nuclear industries due to their different contexts, had significant differences and they vary from 34% for industrial radiography to 65% for nuclear installations.
Conclusion: The existence of LO conditions in the working environment is linked to high safety culture. Thus, the LO can be joined to the toolbox of consultants, managers, and other organizational developers attempting to advance the conditions for safety at work.

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Introduction: In process industries, some of the primary events may result in secondary events in an industrial unit called the domino effect. Since refinery storage tanks are always at risk of fire and explosion, quantitative risk assessment is important in determining the severity and outcome of an accident, taking into account the effects of dominoes on the main industry, neighbors, and society and can play an important role in risk management. Therefore, the purpose of this study was to quantitatively evaluate the risk of condensate storage tanks taking into account the domino effect.
Material and Methods: The technique used in this study was Quantitative Risk Assessment (QRA), the analysis of the consequences of which was performed using PHAST (7.22) after setting goals, studying the process, identifying hazards and scenarios. Then, to determine the extent of the domino effects of the escalation vectors were matched against the threshold, and after screening, the overall vulnerability of the repositories for mapping individual risk levels was calculated.
Results: In the leakage scenario, after considering the domino effects, the risk contour 10-4 to about 250 meters and the risk contour 10-5 to about 400 meters increased. Also in the catastrophic rupture scenario, the radius of risk contour of the 10-5 increased to100 m after considering the domino effects up to around damage tank.
Conclusion: As can be deduced from the results, using this method can give a clear picture of the consequences of chain events and the probability of damage to nearby employees, equipment and neighbors, which is very important in risk, emergency and crisis management.

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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.

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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.

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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).