Natech Accidents Research Articles

Evaluation of natech criteria in organized industrial zones: An application for Kırıkkale province

Natural disasters are unexpected natural events that cause severe property loss and moral damage. Türkiye has been exposed to many disasters due to its location. One of the disasters experienced is the Kahramanmaraş earthquake that occurred on February 6th, 2023, in the recent past. Two consecutive earthquakes caused significant loss of life and property. In addition, some technological accidents happened because of the earthquake. The biggest of these was the fire in the Iskenderun marina. After the earthquake, the big fire that started with the fire of the containers on the quay could be brought under control after a long effort and time. Although it is often overshadowed by natural disasters, technological accidents triggered by natural disasters (Natech) accidents can cause severe damage. Especially Organized Industrial Zones (OIZ) are in areas with high Natech risk. This study determined 10 criteria that will cause Natech accidents for OIZs by literature review. The Pythagorean Fuzzy Analytical Hierarchy Process (PFAHP) method is used to weight the criteria. Then, a ranking is made using The Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method among the five sectors operating in Kırıkkale OIZ and which may have Natech risk.

Ranking of sectors in organized industrial zones according to Natech risk criteria: An application for Gaziantep province in Türkiye

Technological accidents triggered by natural disasters are called Natech accidents. Natech accidents have the impact of increasing the negative effects of disasters. One of the places at risk for a Natech accident is the Organized Industrial Zones (OIZs), where many industrial establishments are located. Although businesses within OIZs are evaluated in terms of security, Natech risk assessment is often ignored. This situation causes Natech accidents to occur. For these reasons, the study focused on evaluating OIZs regarding Natech risk. Many criteria such as electrical resources, natural gas, distance between buildings and so forth are taken into account in Natech's risk assessment. However, it is challenging to make clear decisions and predictions about these criteria due to the nature of the disaster. There is inherently uncertainty and confusion during and after a disaster. For this reason, using fuzzy sets to evaluate criteria is more appropriate. Therefore, the study uses Pythagorean fuzzy sets, which have a wider fuzzy evaluation area. This study also includes the evaluation of alternative sectors in terms of Natech risk. For this purpose, Pythagorean Fuzzy Analytic Hierarchy Process (PFAHP) and Pythagorean Fuzzy the Technique for Order of Preference by Similarity to Ideal Solution (PFTOPSIS) methods are used. OIZ in Gaziantep has the largest area compared to those in other cities in Türkiye, is chosen as the application area of the study. As a result of the study, it is determined that the release of hazardous substances and flammable criteria is the most crucial criterion, and the most dangerous sector in terms of Natech risk is the chemical sector.

Enhancing emergency response planning for natech accidents in process operations using functional resonance analysis method (FRAM): A case of fuel storage tank farm

Recent increases in climate-induced natural disasters have amplified the risk of Natech (natural hazard-triggered technological) accidents, particularly in the chemical industry. These emergencies, characterized by their urgency and resource constraints, pose significant challenges for emergency planning. The Functional Resonance Analysis Method (FRAM) offers a systematic approach to enhance emergency response strategies. This study introduces a FRAM-based methodology specifically designed for fuel storage tank farms, structured into four critical stages: understanding, designing, analyzing, and enhancing the response process. It promotes a cycle of continuous improvement. A case study on a seismic Natech incident at a fuel storage facility demonstrates the methodology's effectiveness and its potential to boost the resilience of emergency response systems against Natech challenges.

Accidents With Oil Spills Triggered by Natural Hazards

In addition to direct social and economic damage, natural hazards also have a devastating impact on technological facilities, which may trigger accidents at these infrastructures. Especially dangerous consequences for the population and the environment are caused by such natural hazard triggered technological accidents (Natechs), which may result in the release of various hazardous chemical substances including mineral oil. This paper analyzes Natech accidents involving spills of oil and oil products. The materials of the author’s database of technological and natural hazard triggered technological accidents occurred in Russia since 1991 are used as initial information for the analyses. The types of natural hazards and adverse natural phenomena that caused accidents with oil spills on the territory of Russia in 1991-2021 are identified. Natechs make up about 6% of all accidents with oil spills. The main triggers of these accidents are hydrological and meteorological hazards such as strong winds, storms, floods, melt waters, rainfalls, lightning, snow loads, and heat wave, as well as landslides and other ground movements. Earthquakes caused the largest damage, but they are less frequent events in Russia. More often, mineral oil leaks occur as a result of ship accidentsor the destruction of oil storage facilities and pipelines. The regions of the greatest risk of accident occurrences with oil spills in Russia are identified.

Emergency response in cascading scenarios triggered by natural events

Emergency response is a procedural safety barrier of paramount importance for the mitigation of fire scenarios and the prevention of escalation. However, in Natech scenarios, emergency response may be affected by the natural event impacting the site. Indeed, when contrasting Natech accidents, emergency responders have to face both the natural event and the cascading technological scenario. Despite the criticality of the issue, limited attention was devoted to date to the analysis of emergency response in cascading sequences triggered by natural events. The present study provides a novel and technically sound methodology to assess the performance of emergency response and the required intervention time in Natech scenarios. An expert survey combined with a Bayesian Network model was used to assess the performance of the emergency response. The routing and setup phases were identified as those mostly affected by natural events. Monte Carlo simulations were used to obtain baseline data and specific probability distributions for the time required to carry out the emergency response considering the factors that may hinder the response during natural events. In Natech accidents, the time for effective mitigation resulted higher of at least a factor 2 with respect to that expected in the case of conventional accidents. The methodology developed may be used to support the improvement of the emergency management of Natech scenarios, allowing for a detailed definition of site-specific emergency response plans. Moreover, the results may be used to provide a more accurate assessment of the fire-driven escalation probability in Natech events.

Is critical infrastructure safe from wildfires? A case study of wildland-industrial and -urban interface areas in South Korea

Global climate change, global warming, and unplanned urbanization have resulted in industrial facilities and livelihoods encroaching on wildlands. Wildfire risks concerns about natural hazards triggering technological accidents (Natech) caused by wildfires in wildland-industrial and -urban interface areas are globally increasing. As wildfires that could trigger Natech accidents occur infrequently but often with unpredicted and uncontrollable consequences, critical infrastructure and industrial facilities should prepare for the potential catastrophic impact of wildfires beforehand. This paper describes a case study of wildfire-threatened critical energy infrastructure located in wildland-industrial interface (WII) and wildland-urban interface (WUI) areas in South Korea. The energy infrastructure avoided a serious Natech accident through intensive risk and emergency management. Although there was no Natech disaster or dreadful damage to the energy facility, this threat to the energy infrastructure is a reminder to prepare for future Natech disasters in WII and WUI areas that could result in unmanageable consequences. This study highlights the need for intensive and integrated wildfire-specific Natech risk management, considering critical infrastructure and industrial facilities in WII and WUI areas, that should include all stakeholders with local residents and enhance Natech resilience.

A Quantitative Framework for Propagation Paths of Natech Domino Effects in Chemical Industrial Parks: Part I—Failure Analysis

Along with global climate change and industrialization, domino effects caused by Natech events occurred frequently in chemical industrial parks over the past decades. Previous research has not yet proposed a reliable method to obtain all possible paths of Natech domino effects, and moreover, a risk assessment and mitigation system has not been established. The present work aims to develop a quantitative framework for propagation paths of Natech domino effects, which can effectively safeguard the sustainable development of chemical industrial parks. The presentation of this work is divided into two parts: Part I (current paper) proposes a path probability calculation method that can simultaneously consider multiple primary accident scenarios and multi-level domino effects triggered by natural disasters. The proposed method transforms the propagation paths of domino effects into the paths of directed graph by constructing the equipment failure state transition matrix and the equipment failure state transition probability matrix. The depth-first traversal algorithm is used to obtain all possible propagation paths and their propagation probabilities, providing data support for the quantitative risk assessment and prevention and control measures presented in the accompanying paper (Part II). The case study shows that the probability of equipment failure caused by multi-level domino effects triggered by Natech accidents is higher than that of conventional accidents. However, the present work only considers the spatial propagation of domino effects, while their spatio-temporal propagation remains as a further direction for this area of inquiry.

Natech Accidents Triggered by Heat Waves

Natech accidents have an increasing relevance due to the growing number of such events and to their severe consequences. Climate change and global warming are intensifying the occurrence and the magnitude of climate-related natural events, further increasing the risk of cascading sequences triggered by natural disasters impacting industrial installations. The present study focuses on Natech triggered by heat waves. The features of this specific category of Natech events were investigated by past accident analysis, collecting an extended dataset of past events. The dataset analysis allowed the identification of the key factors that characterize these accident scenarios, such as the direct causes, the technological scenario that occurred, the substance categories, and the equipment items more frequently involved. The main direct cause of accidents resulted in an internal pressure increase, exceeding equipment design limits. Fire scenarios represent the most important category of technological scenarios that occurred. Besides equipment items handling liquid and gaseous hydrocarbons, waste storage and processing systems also resulted frequently in accidents, due to the self-decomposition and self-ignition phenomena. The analysis of past accidents also allowed identifying some lessons learned, useful to identify specific actions aimed at preventing and/or mitigating the possible occurrence of these accident scenarios.

Scenario deduction of Natech accident based on dynamic Bayesian network: A case study of landslide accident in a liquor storage tank area in Guizhou Province, China

Industrial technical accidents caused by natural disasters are defined as Natech accidents, such as earthquakes and landslides, which can cause tremendous damage to industrial storage tanks, and lead to accidental leakage and even serious fire and explosion accidents. In this study, a landslide-induced storage tank accident model under earthquake disasters was proposed, and the relationship between landslide mass impact and target impact resistance was taken into account. Also, tank failure and the formation of the pool fire were considered to be the consequences of the Natech accident. Through scenario deduction, the dynamic process of landslide Natech was transformed qualitatively into a disaster chain network diagram composed of a scenario state, a disaster-causing factor and emergency management. The Bayesian network was used to learn and deduce the parameters of the network diagram, and in this process, the prior probability and conditional probability of nodes were obtained primarily by Monte Carlo simulation, and by an improved expert scoring method based on the fuzzy set theory. Through visualization software, the sensitivity analysis of landslide Natech was achieved. Finally, a case study of a liquor storage tank area in Guizhou Province, China was carried out, and the results show that a large amount of hazardous material leakage caused by buckling is key to the formation of pool fire accidents, and several prevention measures for earthquake-induced landslide Natech was proposed according to the sensitivity analysis.

Social vulnerability assessment for an industrial city in Natech accidents: A Bayesian network approach

ABSTRACT China is a large industrial country where tropical meteorological disasters occur frequently. Therefore, natural-technological (Natech) risk cannot be ignored. Assessing the social vulnerability of an industrial city prone to tropical meteorological disaster-induced Natechs is urgent. To analyze the social vulnerability of such cities, we propose a Bayesian network (BN)-based method to model the social vulnerability framework. Natech is characterised by high-consequence and low-probability. The industrial cities in Southeast China are selected as a case study. The Monte Carlo method simulates the data generated in industrial cities suffering from tropical disaster-induced Natechs, and the conditional probability tables of BN descendant nodes are obtained by the expert scoring method. After sensitivity analysis, we conclude that the ‘catastrophic index of tropical cyclones,’ ‘population density,’ and ‘prevention capacity’ have important impacts on social vulnerability. Human traits, the social environment, and the economy play important roles in social vulnerability assessments. Therefore, reducing the catastrophic index of tropical cyclones and population density and strengthening prevention capacity management measures are necessary. Some suggestions obtained after sensitivity analysis can assist governments in improving disaster prevention and mitigation abilities and formulating urban planning policies for sustainable development. Highlights Industry city’s vulnerability analysis for Natural-technological (Natech) accidents A social vulnerability assessment framework for sustainable development A Bayesian network combined with the Monte Carlo simulation data and expert judgment Risk management for high-consequence and low-probability events

Risk Analysis of Natech Accidents Trigged by Lightnings and Floods

Natural Hazard Triggered Technical Accidents (Natech) cause serious loss of life, environment and property and affect life negatively. Risk analysis studies of these accidents are important. In this study, it was aimed to analyze the risk of Natech accidents for Türkiye. Statistical evaluation of Natech accidents was made through various databases for selecting the province and organization where the application will be made. Because of these evaluations, two exemplary gas storage organizations (Organization 1: includes 5 cylindrical tanks of the same volume, Organization 2: includes 4 cylindrical tanks of the same volume and 1 large volume spherical tank) were selected within the scope of the legislation in Erzurum, which stands out in terms of flood and lightning risk. Flood-triggered Natech accidents were analyzed using the preliminary hazard list and Fine-Kinney methods, and lightning-triggered Natech accidents were analyzed through the YILKOMER and RADSAN programs. For Organization 1 and Organization 2, the protection level was determined as 3 and 4, respectively, according to the effectiveness value. While 34 hazard effects were graded with the preliminary hazard list for Organization 1 and 22 hazard effects by Fine-Kinney; for Organization 2, hazard effects were graded 37 with the preliminary hazard list and 28 with Fine-Kinney. Because of the analyses carried out, Organization 2 was found to be more risky in terms of Natech accidents triggered by both lightning and flooding. It can be said that this situation is because the relevant organization is located in a more congested area and within the organized industry, and that it contains more voluminous tanks. It is important that emergency plans be prepared by considering the Natech risks, based on the characteristics of the industrial facility and the type of natural disaster in the region.

Natech accidents triggered by cold waves

Natural events are a widely recognized hazard for industrial sites where relevant quantities of hazardous substances are handled, due to the possible generation of cascading events resulting in severe technological accidents (Natech scenarios). To date, research efforts were mainly dedicated to the study of Natech scenarios triggered by earthquakes, floods, and hurricanes. However, a number of recent events evidenced the potential hazard of Natech scenarios triggered by cold waves and winter storms. The present study aims at providing a comprehensive analysis of past accidents involving hazardous substances triggered by cold waves affecting the industrial infrastructure. A dataset of over 740 Natech events was collected from specialized sources. A detailed analysis of the primary events and damage modes of the equipment items involved was carried out, highlighting that most of the accidents were linked to the phase transition from the liquid to the solid state of the process fluid or of atmospheric water. The analysis of the events allowed the identification of several aspects of the cause-consequence chains, such as the technological scenarios and the equipment items more frequently involved. A specific focus was also on the vulnerability and failure modes of safety barriers. The lessons learned derived from the analysis of the accidents provide key elements to prevent similar accidents from happening in the future. These were used to suggest specific safety barriers integrating winterization and freeze protection programs.

Risk-aware navigation in industrial plants at risk of NaTech accidents

Industrial plants are susceptible to NaTech disasters during earthquakes caused by damage to structural and non-structural components and the potential release of toxic materials. To mitigate and manage this risk, the ROSSINI project was initiated and its results are described here for what concerns industrial plant worker safety and their risk-based navigation in emergency situations. The project includes a data acquisition system consisting of a data acquisition board and an array of different sensor technologies, which process the seismic event and other meteorological information before passing them as inputs towards the risk identification and evaluation (RIE) modules. Here, the risks associated with structural and non-structural damage and health risks associated with the release of harmful substances are estimated and combined to form a navigable risk map. This map is used within a purpose-built risk-based navigation application for the safe egress of workers from an industrial plant. To demonstrate the implementation of this system, two case-study industrial plant layouts consisting of buildings, non-structural components, liquid storage tanks, piping systems, and chemical storage vessels, were devised. This paper describes the project's implementation in these contexts and illustrates the results via several example scenarios.

Cascading Effects of Natural Hazards: Lessons from Recent Natech Accidents and Practices

Recent trends of disaster present that disasters are more uncertain and complex with unpredictable cascading effects owing to global environmental and climate change. As one of the significant phenomena, natural hazards triggering technological accidents, so-called Natech, which cause acute and prolonged terrifying consequences, have also been increased. Considering low probability but high consequences, Natech accidents often exceed the capacity of disaster preparedness and response of local government and professional responders. As a result, the need to better manage Natech risks has become a challenge in disaster risk management among all stakeholders, including government, disaster and safety experts, industry, and citizens. Although there have been numerous efforts undertaken by international organizations and individual countries to reduce Natech risks, there are still not sufficient reflections to reduce the risks of natural hazard triggering technological disasters in South Korea. Thus, this study highlights lessons from Natech risk reduction practices undertaken by individual countries and recent minor Natech cases to fullfill gaps in effective risk management considering for cascading effects.

A framework of sensitivity analysis for the performance assessment of safety barriers impacted by NaTech accidents

Hazardous Natural events can cascade into Technological accidental scenarios (so called NaTech accidents). The occurrence of these accidents can degrade the performance of the preventive and mitigative safety barriers installed in the technological plants. Such performance degradation is typically assessed by expert judgement, without considering the effect of the magnitude of the natural hazard, nor its increasing frequency of occurrence in view of climate change. In this work, a novel sensitivity analysis framework is developed to identify the safety barriers whose performance degradation is most critical and thus needs careful modeling for realistic risk assessment. The framework is based on the calculation of a set of sensitivity measures, namely the Beta, the Conditional Value at Risk (CVaR) and the Value of Information (VoI),●and their use to prioritize the safety barriers with respect to the need of:●accounting for performance degradation during an accidental scenario;●planning investments for further characterization of the safety barrier performance.An application is shown with respect to a case study of literature that consists of a chemical facility equipped with five safety barriers (of three different types, active, passive and procedural). NaTech scenarios can occur, triggered by floods and earthquakes. The results obtained with the Beta measure indicate that two-out-of-five barriers (one active and one passive) deserve accurate modelling of the performance degradation due to natural events. An additional outcome is that in the case study considered, both CVaR and VoI rank the passive barrier as the most effective in mitigating the scenarios escalation: therefore, this barrier is the one for which the decision maker could decide to invest resources for improving the characterization of its performance to obtain a more realistic assessment of the risk.

A scenario analysis under epistemic uncertainty in Natech accidents: imprecise probability reasoning in Bayesian Network

The increasing frequency and severity of Natech accidents warn us to investigate the occurrence mechanism of these events. Cascading disasters chain magnifies the impact of natural hazards due to its propagation through critical infrastructures and socio-economic networks. In order to manipulate imprecise probabilities of cascading events in Natech scenarios, this work proposes an improved Bayesian network (BN) combining with evidence theory to better deal with epistemic uncertainty in Natech accidents than traditional BNs. Effective inference algorithms have been developed to propagate system faulty in a socio-economic system. The conditional probability table (CPT) of BN in the traditional probability approach is modified by utilizing an OR/AND gate to obtain the belief mass propagation in the framework of evidence theory. Our improved Bayesian network methodology makes it possible to assess the impact and damage of Natech accidents under the environment of complex interdependence among accidents with insufficient data. Finally, a case study of Guangdong province, an area prone to natural disasters, is given. The modified Bayesian network is carried out to analyze this area’s Natech scenario. After diagnostic analysis and sensitivity analysis of human factors and the natural factor, we are able to locate the key nodes in the cascading disaster chain. Findings can provide useful theoretical support for urban managers of industrial cities to enhance disaster prevention and mitigation ability.

Understanding Households’ Perceptions Regarding the Effect of a Natech Accident on Residential Property Values: The Case of Ichihara City

This research investigated households’ perceptions concerning the effects of a natural hazard-triggered chemical accident (known as a Natech) on residential property values in Ichihara city, Japan, where a Natech accident occurred in 2011 following the Great East Japan earthquake and tsunami. Furthermore, the household survey investigated households’ perceptions regarding the effect that the disclosure of risk information concerning potential chemical and Natech accidents on future property values. Data was collected through a stratified random survey of households within three kilometers of the Chiba industrial park in Ichihara City, Japan, where the Natech accident occurred. The household survey findings indicate that the respondents felt that the land price did not decline due to the Natech accident in 2011. However, they consider chemical and Natech accidents a threat to their lives and property. They are concerned that chemical accidents alone or triggered by natural hazards may happen again at the Chiba industrial park and about the potential for the accidents to decline property values in the future. The results also showed that respondents want the government to disclose chemical risk information, but they are also concerned that the disclosure will affect future property values. The study results have implications on Natech risk governance at the community and industry level. The survey results highlighted the need to develop risk communication strategies taking into consideration households concerns, and finding ways to counterbalance the negative effects that the disclosure of risk information may have.

Natech guide words: A new approach to assess and manage natech risk to ensure business continuity

The risk posed by natural hazards to the technological systems is known as Natech risk. It is different from the more widely known and studied risk posed by such sites to the environment and society. Though currently, available risk assessment techniques recognize Natech, the specific qualitative technique for Natech risk assessment and reduction has not yet been developed. After analyzing past data of Natech accidents, relevant guide words have been suggested in this study. These guide words will help anticipate Natech risk and visualize the Natech scenario. Once the Natech risk is identified, corresponding risk reduction measures can be taken to avoid possible Natech accidents and consequences.

Thinking the unthinkable: A perspective on Natech risks and Black Swans

Technological accidents are a threat to the population, the environment and the economy. Occasionally, the notion of “Black Swan” event is applied to such accidents as an explanation for why they could not be prevented. By their very nature, Black Swans are considered extreme outliers which are impossible to anticipate or manage. However, technological accidents are generally foreseeable and therefore preventable when the associated risk is managed responsibly and when warning signs are not ignored. Consequently, such accidents cannot be considered Black Swans. We contend that the same holds for technological accidents triggered by natural hazards (so-called Natech accidents) which usually result from a lack of corporate oversight and insufficient application of state-of-the-art knowledge in managing the associated risk. We argue that the successful reduction of Natech risk requires a corporate mindfulness of the risk and the need to address it using updated approaches, the recognition that organizational behavior influences the risk significantly, and risk ownership that departs from the “Act-of-God” mindset which much of the discussion around natural hazards is fraught with. The study also highlights the importance of scientific research and knowledge management to reduce risks.

Assessment of risk modification due to safety barrier performance degradation in Natech events

Natural hazards may cause severe technological accidents involving hazardous substances (Natech accidents). Along with process equipment also safety critical elements as safety barriers might be impacted by such events, thus reducing the protection provided and the possibility to prevent escalation and cascading effects. In the present study a comprehensive methodology is developed to address the quantitative assessment of the risk caused by the escalation of Natech accidents, specifically addressing the effect of the performance modification of safety barriers caused by the impact of the natural hazard. Barrier performance depletion is modelled through an innovative multi-level approach, and it is then introduced in the quantitative risk assessment procedure by a modified event tree analysis. A demonstrative application of the proposed methodology to a case study is provided, showing a relevant increase in risk figures deriving from the degradation of safety barrier performance caused by natural events. The proposed framework extends the systemic assessment of Natech scenarios to encompass the specific criticalities introduced by safety barrier performance modification induced by natural events, providing a more effective support to decision-making in the management and control of risk deriving from the interaction of natural hazards with technological installations.