A multi-hazard history of Antigua*

Antigua experiences earthquakes, droughts and hurricanes. To isolate for study each of these as they occur, would be to over simplify the inter-relationships between the aftereffects of one and the occurrence and the effects of the next. Moreover, there will be conditions arising from factors outside the natural disaster spectrum which bear upon, and are themselves affected by, all of these phenomena. This interplay of events and conditions is readily illustrated in the case of island countries, which have a natural and clearly defined containment. Such interrelationships suggest a complex human-ecological system which must be recognized if environmental balance and compatability are to be maintained - particularly in respect of hazards. This documentary analysis of the colonial era in Antigua, has to conclude for the time being with questions concerning the environmental effectiveness of imported systems of administration which, with no knowledge of comparable natural hazards, assumed sectoral separation.     

Risk analysis in Natech events: State of the art

Natech events (Natural Hazard Triggering Technological Disasters) are industrial accidents caused by natural events such as hurricanes, floods, earthquakes, tsunamis, and so on. In recent decades, the probability of these events occurring has increased, activating the interest of researchers in the study of new methods of risk analysis to prevent and mitigate possible damage to people, the environment, and processing facilities. On the other hand, the concept of multi-hazard is summarized in the combination of two or more threat factors manifested in isolated, simultaneous manner, or by chain reaction, to produce a trigger event of a disaster, where hazardous events can be one or more natural events. Considering that, it is essential to know the progress in risk analysis for Natech events, to identify the gaps for future research. Therefore, in this paper, a systematic review of the Natech events literature with single and multi-hazard approaches was developed. The review was conducted by searching the Science Direct, Web of Science, and Scopus databases for scientific documents. Subsequently, the words Natech and Multi-hazard were taken as keywords, and 208 results were obtained. Then, some management documents were consulted in international organizations to compare academic literature and industrial risk management. In conclusion, the risk analysis methods revised are specific to a particular hazard and apply mainly to earthquakes, floods, and lightning. Regarding a multi-hazard approach, the methods focus on risk mitigation in urban areas without taking into account Natech risk. In the case of industrial risk assessment, some methodologies were found that briefly consider Natech risk in risk assessment processes in industry.     

Probabilistic seismic multi-hazard loss estimation of Iran gas trunklines

The location of Iran in addition to holding the world's second-largest gas reserves, makes this country an important transporter of natural gas in the world. Moreover, Iran is a country that suffers from hazards associated with frequent destructive earthquakes, which can severely damage buried gas transmission networks, different losses correspond to individuals, social, environmental, and the property is expected. Therefore, it is essential to identify potential seismic hazards and assess their risk will be induced to the country. This paper is performing a comprehensive probabilistic loss assessment of the entire network of the Iran Gas Trunklines (IGAT) due to seismic multi-hazard failure using GIS-based analyses and the HAZUS methodology proposed by FEMA. In the current study, all kinds of seismic hazards are considered for analyzing the IGAT as a spatially-distributed infrastructure for being exhaustive. As a result, seismic hazard maps, repair rate maps, the IGAT expected damage state map, and the IGAT economic loss map are presented. As an example of the outputs of this study, the economic loss of the IGAT is predicted by up to 380 US dollars per segment, which is related to the most vulnerable segments of the pipelines. The outputs of the current research not only can help to plan for mitigating the probable seismic losses but also can help anyone, who are involved in designing and developing new gas transmission lines, to design new trunklines with a more degree of safety.     

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.