Explosion at an aluminum factory caused by the July 2018 Japan floods: Investigation of damages and evacuation activities

An explosion at an aluminum factory occurred due to floods in Soja City, Okayama Prefecture, in July 2018. This study investigates the accident, its overall impact on local residents, and emergency management activities. The results of the study showed that several nearby structures and homes were damaged by the explosion. Concern for more explosions has led to the evacuation of residents of Shimobara area of Soja City. In Shimobara, residents had carried out voluntary disaster prevention activities before the disaster. After the explosion, Shimobara residents were able to evacuate safely in cooperation with the voluntary disaster prevention organization and the local government agency. The study revealed that there was a lack of information on chemical accident hazards shared by the factory with local government authorities and first responders, as well as with local residents. In order to be better prepared for technological accidents, and in particular accidents caused by natural disasters (known as Natechs), mechanisms for information sharing between companies and municipalities should be adopted.     

Research on three-dimensional visualization system of Natech events triggered domino accidents in oil-gas depots

Natech events and domino accidents happen worldwide and usually lead to severe consequences, especially in hazardous areas such as Oil-Gas depots. With the continuous development of the Oil-Gas industry and information technology, it is essential to realize the three-dimensional management and monitoring of hazardous substances. To evaluate the consequences caused by Natech events triggered domino accidents (accident chain), a matrix loop method was proposed to calculate the probability and evolution path of the accident chain. The actual layout and the real-time data of the Oil-Gas depot are input into the evaluation method in matrices, thus making the results reliable and updated. Besides, a B/S architecture system is developed to present the evaluation consequences of the proposed method. The three-dimensional visualization effects of natural disasters, technological accidents and the dynamic propagation process of the accident chain are also realized in the system to enhance the user's experience. A system application regarding lightning-triggered domino accidents was carried out to demonstrate the feasibility and rapidity of the proposed evaluation method and perform the system's operation process and visualization effects. The application results show that the system can provide effective decision-making assistance to safety management workers before the accident and guidance for emergency rescue operations during the accident.     

Quantitative risk assessment of domino effect in Natech scenarios triggered by lightning

Lightning strike is the natural event more frequency causing Natech accidents involving atmospheric storage tanks. Despite the resulting fires have usually limited severity and only local effects, domino effect may cause the escalation of these primary events, possibly affecting nearby pressurized storages and process equipment, thus resulting in relevant increase in the potential area impacted. A methodology was developed for the quantitative assessment of risk due to domino effects caused by Natech accidents triggered by lightning. A comprehensive procedure was obtained, tailoring lightning risk assessment to include probabilistic models for domino escalation based on probit approach and combinatorial analysis. The methodology was applied to a case-study to evidence the shift in risk figures due to domino effect and the credibility of the secondary domino scenarios. The results of the case-study show that an increase up to two orders of magnitude with respect to risk calculated for conventional scenarios is possible when considering lightning-induced Natech primary scenarios and their escalation.     

Multi-hazard failure assessment of atmospheric storage tanks during hurricanes

Hurricane as one of the most destructive natural hazards can make a devastating impact on the industrial equipment, especially atmospheric storage tanks, leading to the release of stored chemicals and disastrous safety and environmental issues. These catastrophic consequences are caused not only by strong winds but also by the torrential rainfall and inundating floods. The objective of this study is to present a risk-based methodology for assessing and reducing the vulnerability of atmospheric storage tanks to hurricanes. Considering the shell buckling, flotation, sliding, and roof sinking as dominant failure modes of atmospheric storage tanks during hurricanes, Bayesian network (BN) has been employed to combine the failure modes while considering their conditional dependencies. The probability updating feature of the developed BN was employed to indicate that the flood is the most critical hazard during hurricanes while the impact of wind and rainfall cannot be neglected. Extending the developed BN to an influence diagram, the cost-benefit filling of storage tanks with water prior to the advent of hurricanes was shown as a viable measure for reducing the damage probability. The results show that the proposed methodology can be used as an effective decision support tool for assessing and reducing the vulnerability of atmospheric storage tanks to natural hazards.     

Understanding the patterns and characteristics of Natech events in China

With the frequent occurrence of natural disasters, natural hazard triggered technological accident (Natech) risk has attracted extensive attention from academia and industry. Natech events have the characteristics of various inducements and consequences, cascading chain reactions, and complex spatial interleaving, which leads to serious consequences. The Natech event is constantly threatening China's industrial safety production. However, the systematic analysis of Natech events in China is still lacking. The study counted 288 cases in the past 20 years and constructed Natech databases. Based on the theory of risk chain and risk system, a systematic horizontal and vertical analysis was developed for the first time. It aims to understand the characteristics of Natech events in terms of temporal and spatial, hazard factors, industry and risk material, consequences and hazard. In the results, Natech events showed a fluctuating trend. The southwest region (28.13%) and the middle Yellow River region (21.18%) belong to the critical control areas. China's industries were seriously affected by the disasters of meteorological (43.75%) and secondary, especially in the Chemical & Petrochemical and manufacturing. 64.58% of Natech events caused environmental pollution, and 13.19% of Natech events caused major or above consequences. Oil (31.25%) and hazardous chemicals (28.47%) were the main substances causing pollution, fire and explosion, which need to be controlled. The research preliminarily clarifies the risk chain and characteristics of Natech events, which provided the basis for Natech risk assessment.