•We investigated the accident of the MV SEWOL through four accident theories.•Total of 23 causes has been identified from the theories.•None of the theories can explain the entire causes and sequence ...of the accident.•We discussed combination of the theories for accident investigation and prevention.
On 16th April 2014, the MV SEWOL capsized in South Korea, and 304 persons died or went missing. This article describes the accident and finds causes from four different theoretical points of view: the energy-barrier model, Turner’s man-made disasters model, Rasmussen’s conflicting objectives perspective, and high reliability organizations theory. The results show that the theories together point out a total of 23 different causes to the accident. Different causes are identified from different theories and they complement each other. Finally, this article discusses a possible combination of the perspectives for improving both accident investigation and accident prevention.
Inherently safer design is the most proactive approach to manage risk, as referred by scientists and experts. Researchers have adopted various methods in evaluating inherent safety indices like ...parameter-based indexing, risk-based indexing, consequence-based indexing, etc. However, the existing approaches have their limitations. The present paper focuses on establishing an inherent system safety index (ISSI) to evaluate inherently safer design during the concept development stage. The analysis starts by identifying a non-harmful system's inherent safety characteristics and related parameters. Four subindexes, determined from the non-harmful system's characteristics, are established using their relevant parameters. The safety of the chemical process system, the health of workers, and the environment's safety can be assured by selecting relevant parameters. Parameters are scored based on their deviation from the non-harmful condition. The sum of the deviations of the parameters gives the value of the inherent safety index. The case study looks at various routes of Methyl Methacrylate (MMA). According to the present case study, MMA production followed by Tertiary butyl alcohol is the safest route given health, safety, and environmental perspective. This approach helps overcome the limitation of parameter-based indexing, which arises from selecting predefined fixed parameters that become invalid in case of system variation or significant modification of the system. Besides, it considers the complexity and vulnerability that arises from the interaction of various factors|, which increase predetermined risk calculated at the design stage when the system is in operation. The subindices can be used individually if a focus is needed in a definite section of a system with a particular application or a smaller portion. This method is helpful for the industry in designing a safer plant considering the health, safety, and environmental perspective at the concept development stage.
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•The paper develops a new safety index which is inherent system safety index (ISSI).•ISSI identifies system's inherent safety characteristics and related parameters.•The method can be updated anytime for system variation or significant modification.•Subindices can be used distinctly to give focus to a specific requirement.•Various routes of Methyl Methacrylate production are considered in the case study.
The contributions cover a wide range of methodologies and application areas for safety and reliability that contribute to safe societies in a changing world. These methodologies and applications ...include: - foundations of risk and reliability assessment and management - mathematical methods in reliability and safety - risk assessment - risk management - system reliability - uncertainty analysis - digitalization and big data - prognostics and system health management - occupational safety - accident and incident modeling - maintenance modeling and applications - simulation for safety and reliability analysis - dynamic risk and barrier management - organizational factors and safety culture - human factors and human reliability - resilience engineering - structural reliability - natural hazards - security - economic analysis in risk management
•A high level of complexity and automation has brought new challenges to risk management.•An extended FRAM method is applied to find necessary safety barriers in the system.•FRAM can give a quick way ...to check the adequacy of safety barriers.•Extended FRAM is applied to assess safety based on the performance of the barriers.•Comparison is made among FRAM, FRAM-STPA, Bow-tie, and Bayesian network.
Safety barriers are used in the system to prevent unwanted events and accidents. Traditional approaches like fault tree or bow-tie method use linear accident models without considering complex interactions of failures of safety barriers. The present paper presents an extended FRAM model to identify required safety barriers and proposes a safety analysis method to predict the system's safety. The initial step of the method is to identify the necessary main and auxiliary functions to achieve the system goal. The later step is to determine the necessary safety functions to execute the main functions to achieve the system goal and to resist variability in performing the main and related auxiliary functions. A simple mathematical model is proposed to assess system safety based on the performance of existing barriers. The method is described with the help of a case study, the LNG ship-to-ship transfer process. The paper compares the extended FRAM method with other methods such as Bow-tie, FRAM-STPA, and Bayesian network. Analysis shows that FRAM can qualitatively, quantitatively, and dynamically assess system safety. The most vital point of FRAM lies in its capability of effective qualitative evaluation, which considers coupling between functions and related aspects, can be presented graphically, and future actions can be taken accordingly.
•Classification of decision situations to target different aspects of risk that need to be expressed.•Five types of risk information for supporting decisions from general to ...context-specific.•Application of classification scheme to a case related to leaking Emergency Shutdown Valves in a process plant.
Application of risk assessments developed for the design phase to support decision-making in operational settings has exposed weaknesses in how risk is analysed and expressed in an operational context. The purpose of this paper is to clarify what we actually need to express when we use risk information to support various decision scenarios. We distinguish decision scenarios into strategic decisions, operational decisions, instantaneous decisions and emergency decisions. This forms a basis for discussing the different role risk and risk assessment plays in these decisions. Five categories of risk information (average risk, site-specific average risk, activity risk (activity performance risk and activity consequence risk), period risk and time-dependent action risk) are proposed and applications for different types of decisions are discussed. An example illustrates the use of the proposed risk types. The classification has novel aspects in providing a structure that should help in understanding how we need different aspects of risk and different ways of expressing risk in different situations. In addition, it improves communication among decision-makers by clarifying what aspects we are addressing when we use the term “risk”.
•Activity Performance Risk is a key input to operational planning decisions.•A generic list of activity factors is proposed based on major accident theories.•The list provides an overview of factors ...that determine risk involved in activity.•The list can also facilitate accident investigation on operational level.
Operational Planning Decisions, which are characterized by short planning time and high frequency in the operational phase, has received little attention in risk and safety research in oil and gas industry. Activity performance risk, as an important part of the input to such decisions, must reflect explicitly the critical factors (Safety Critical Parameters) that determine the risk level involved in the activity. The paper looks into major accident theories that are relevant for the operational phase to find key concepts and implications for activity performance risk analysis. A generic list of Safety Critical Parameters is developed to assist managing both identified and unidentified risk in the activity. The main conclusion is that the different theories are not conflicting but supplementing to get the list that covers the most important factors in a broad sense. This list provides a guide to Operational Planning Decision makers to collect systematically activity-related risk information to ensure a safe activity.
•Systematic review on risk analysis models within shipping in ice-covered waters.•Clarifications of the accident in ice-covered waters.•Overview of risk factors affecting shipping in the ice-covered ...waters.•Gaps of knowledge to guide future research.
With the changing climate and declining extent of sea ice, the activities in the Arctic region have become increasing significantly. Compared to the environments with ice-free waters, the harsh environment in the Arctic is due to ice, low temperatures, remoteness, etc., all of which will complicate ship operations. Research on the shipping risk analysis in ice-covered waters is important because such research can improve the management of shipping businesses and aid accident prevention initiatives in the Arctic. In this paper, we systematically review and compare risk models for shipping in ice-covered waters to report experiences in the field and to identify existing knowledge gaps. This work provides a broad review and comparison of the state-of-the-art risk analysis models by considering the models’ purposes, theoretical frameworks, risk factors, and outputs, and it includes an analysis of the field-specific terminology that is used to define accidents. The results indicate that the risk analysis of the Arctic faces challenges, as a complete overview of accident data is not easy to find. There has been significantly less research done on convoy operations in ice and overtaking and meeting in an ice channel. In addition, interactions between risk factors and human factors are not sufficiently understood and thus need to be further studied. Being familiar with knowledge gaps acts as a catalyst for further research on risk analysis within shipping in Arctic conditions.
Marine Autonomous Surface Ships (MASS) are tested in public waters. A requirement for MASS to be operated is that they should be at least as safe as conventional ships. Hence, this paper investigates ...how far the current ship risk models for ship-ship collision, ship-structure collision, and groundings are applicable for risk assessment of MASS. Nine criteria derived from a systems engineering approach are used to assess relevant ship risk models. These criteria aim at assessing relevant considerations for the operation of MASS, such as technical reliability, software performance, human-machine interfaces, operating, and several aspects of communication. From 64 assessed models, published since 2005, ten fulfilled six or more of these criteria. These models were investigated more closely. None of them are suitable to be directly used for risk assessment of MASS. However, they can be used as basis for developing relevant risk models for MASS, which especially need to consider the aspects of software and control algorithms and human-machine interaction.
•Developed criteria for ship risk models applicability to autonomous ships.•None of the models could fulfil all criteria, but some can be used as starting point.•Bayesian belief networks seem to be a suitable tool for modeling and should be considered.•Models developed for traffic risk assessment are not suitable for individual ships.
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