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Research paper thumbnail of Risk Assessment of Major Accidents Triggered by Lightning Events

The analysis of major industrial accident databases indicates that lightning events are the most ... more The analysis of major industrial accident databases indicates that lightning events are the most frequent cause of technological accidents triggered by natural events in chemical and process plants. Severe fires, mainly affecting storage farms, are the most frequent final scenario associated to such events. In the present study, a quantitative methodology for the assessment of the risk due to major accidents triggered by lightning is presented. The methodology was developed within a common framework for the quantitative assessment of risk due to external hazard factors in chemical and process plants. The procedure also allows the identification of the credible scenarios that may be associated to the different modes of structural damage and the identification of critical equipment items.JRC.DG.G.7-Traceability and vulnerability assessmen

Research paper thumbnail of Assessment of the Probability of Structural Damage due to Lightning Impact on Process Equipment in the Chemical and Process Industry

A detailed analysis of past accidents evidenced that lightning strikes on storage or process vess... more A detailed analysis of past accidents evidenced that lightning strikes on storage or process vessels containing flammable materials may cause severe accidents at refineries, storage sites, processing sites and other industrial facilities where hazardous materials are stored or processed. Although the hazard due to lightning is well known and is usually considered in the safety analysis of chemical and process plants, well accepted quantitative procedures to assess the contribution of accidents triggered by lightning to industrial risk are still lacking. In particular, the approaches to the assessment of lightning strike probability, damage caused by lightning strike and intensity of loss of containment (LOC) caused by lightning are mostly based on expert judgment and not on up-to-date models that take into account the relevant progress made in the last years in the analysis of the lightning phenomenon. In the present paper an innovative procedure for the quantitative assessment of the industrial risk due to LOC of hazardous substances triggered by lightning is introduced. The study was focused on the development of models for lightning impact probability and for damage probability. In particular, a Monte Carlo approach was developed to calculate the probability of lightning impact on the basis of the geometry of the structure and of lightning intensity and frequency data.JRC.DG.G.7-Traceability and vulnerability assessmen

Research paper thumbnail of A novel framework for the quantitative assessment of risk due to major accidents triggered by lightning

Research paper thumbnail of Assessment of major accidents triggered by lightning

CRC Press eBooks, Aug 25, 2009

The present study aimed at the analysis of past accidents caused by lightning and the development... more The present study aimed at the analysis of past accidents caused by lightning and the development of a framework for the quantitative assessment of these events. The analysis of past accidents suggests that lightning events are the most frequent cause of technological accidents in chemical and process plants. Fires, mainly affecting storage farms and involving atmospheric storage tanks, are the most frequent final scenario associated to such events. The development of a quantitative methodology for the assessment of the risk due to major accidents triggered by lightning was thus addressed. The starting point of the methodology is the assessment of the frequency and severity of the lightning event. Different damage states were defined, and damage probability functions were derived. The overall frequency and intensity of loss of containment were thus determined. Standard models for consequence analysis allowed the assessment of the physical effects of the final scenarios.JRC.G.7-Traceability and vulnerability assessmen

Research paper thumbnail of Iclp 2010 Monte Carlo Based Lightning Risk Assessment in Oil Plant Tank Farms

Research paper thumbnail of Acceptability parameters for industrial risk with respect to natural-technological interactions

When industrial risks are of concern, local operators, safety management and public authorities a... more When industrial risks are of concern, local operators, safety management and public authorities are generally focused on technological risk sources, management deficiencies or human errors, but are often unaware of possible accidental scenarios which may derive from the impact of disastrous natural events as earthquakes, flooding or lightning on industrial establishments (Na-Tech hazard). This issue has been recently recognized by the European Community, which has financed a large-scale integrated project within the Seventh Framework Program, concerning the early recognition, monitoring and integrated management of risks related to emerging and new technologies (iNTeg-Risk). In the project, a specific task has been devoted to assess the contributions of Na-Tech risks to the overall industrial risk at community level, aiming at the improvement of the resilience of industrial facilities to technological accidents triggered by natural hazards. In the following, a general procedure for the evaluation of Na-Tech risks having considered floods, lightning and earthquakes, with specific reference to large scale equipment containing hazardous substances, is presented. Preliminary results of specific methods developed for the Quantitative Risk Assessment of industrial facilities and areas exposed to Na-Tech events are discussed. These results have clarified that the contribution of natural events to the industrial risks may be important and comparable to the purely technological risks. Furthermore, they allow the definition of priorities for the prevention and mitigation of accidental scenarios in terms of safety management, early warning systems and/or technological resources. The study also focused on the acceptability criteria for industrial installations with respect to the accidental events triggered by natural events. Important differences may arise if a classical reference for the acceptability matrix (e.g. the ALARP matrix) is used. The natural event recurrence period and the probability of its intensity and the hazard of top events require very different procedures for their estimation. Historical data are essential for natural events whereas they are less significant for industrial equipment, due to the continuous development of safety system and technology. Moreover, the figure for \u201cfrequent event\u201d in the industrial risk matrix has a correspondent \u201cvery rare\u201d figure for natural event in the geophysical or meteorological meaning, and the external environment is generally struggling for the natural event and overloading of public emergency systems does not allow a contribution for the industrial accidental scenario mitigation. Also, combined scenario occur when natural events strike any industrial installation, and mitigation systems are often affected at the same time, whereas single, partially mitigable scenarios are generally predicted in the normal process life and industrial safety assessment. Finally, the natural event effects may contribute to the overall risks as workers may be injured directly for the same event of for the structural damage of buildings, offices and steel structures inside the installation. In this framework, the possible definition of acceptability parameters based on threshold values for the natural events, either in terms of Na-Tech accidental scenario probability of occurrence or for the relative intensity was investigated. The proposed threshold values were obtained from the threshold values of the specific equipment categories, for each natural event, that were obtained in previous studies and from the analysis of the societal risk variation as obtained from QRA analysis

Research paper thumbnail of Monte Carlo based lightning risk assessment in oil plant tank farms

2010 30th International Conference on Lightning Protection (ICLP), 2010

Research paper thumbnail of Awareness and mitigation of NaTech accidents: Toward a methodology for risk assessment

Natural hazards affecting chemical and process facilities deserve particular attention since they... more Natural hazards affecting chemical and process facilities deserve particular attention since they can cause the release of hazardous substances possibly resulting in severe environmental pollution, explosions and/or fires (so-called NaTech accidents). Awareness of the hazard posed by Natech events in growing, and a need for explicitly including NaTech accidents into chemical-accident prevention and mitigation is nowadays widely recognized. Nevertheless, several elements that characterize Natech events still need to be investigated. In particular, only scarce data exists on equipment damage modes, release intensities and the final consequences for these accidents. The present contribution focuses on the development of a general framework for the assessment of NaTech risk. The analysis of past accident data allowed the gathering of data on the expected damage of process equipment caused by the impact of flood, lightning and earthquake events. Failure modes and damage states caused by ...

Research paper thumbnail of Equipment Failure Probability due to the Impact of Lightning

The historical analysis of accidental scenarios triggered by lightning shows that the impact of a... more The historical analysis of accidental scenarios triggered by lightning shows that the impact of a lightning on a process plant might be the initiating event of a severe accident. The analysis identifies the most common damages to the equipment as either immediate ignition of flammable atmospheres or structural damage with subsequent release. However, the available information on lighting damage to industrial equipment is fragmented and not very detailed. The aim of the present study is to define a failure model for reference equipment categories following lightning impact. Starting from the analysis of lightning damage, the possibility of equipment damage is assessed on the basis of lightning characteristics. The probability of failure is evaluated as the probability to find, in impacting lightning strikes, the minimum energy necessary to cause the loss of containment of the selected equipment. Probability distribution functions available for lightning characteristics, used together...

Research paper thumbnail of An Approach to the Quantitative Assessment of Risk Due to Natech Events

Transactions of the VSB - Technical University of Ostrava, Safety Engineering Series, 2012

Research paper thumbnail of Assessment of major accidents triggered by lightning

Theory and Applications, 2009

The present study aimed at the analysis of past accidents caused by lightning and the development... more The present study aimed at the analysis of past accidents caused by lightning and the development of a framework for the quantitative assessment of these events. The analysis of past accidents suggests that lightning events are the most frequent cause of technological accidents in chemical and process plants. Fires, mainly affecting storage farms and involving atmospheric storage tanks, are the most frequent final scenario associated to such events. The development of a quantitative methodology for the assessment of the risk due to major accidents triggered by lightning was thus addressed. The starting point of the methodology is the assessment of the frequency and severity of the lightning event. Different damage states were defined, and damage probability functions were derived. The overall frequency and intensity of loss of containment were thus determined. Standard models for consequence analysis allowed the assessment of the physical effects of the final scenarios.JRC.G.7-Traceability and vulnerability assessmen

Research paper thumbnail of Industrial accidents triggered by flood events: Analysis of past accidents

Journal of Hazardous Materials, 2010

Research paper thumbnail of Industrial accidents triggered by lightning

Journal of Hazardous Materials, 2010

Natural disasters can cause major accidents in chemical facilities where they can lead to the rel... more Natural disasters can cause major accidents in chemical facilities where they can lead to the release of hazardous materials which in turn can result in fires, explosions or toxic dispersion. Lightning strikes are the most frequent cause of major accidents triggered by natural events. In order to contribute towards the development of a quantitative approach for assessing lightning risk at industrial facilities, lightning-triggered accident case histories were retrieved from the major industrial accident databases and analysed to extract information on types of vulnerable equipment, failure dynamics and damage states, as well as on the final consequences of the event. The most vulnerable category of equipment is storage tanks. Lightning damage is incurred by immediate ignition, electrical and electronic systems failure or structural damage with subsequent release. Toxic releases and tank fires tend to be the most common scenarios associated with lightning strikes. Oil, diesel and gasoline are the substances most frequently released during lightning-triggered Natech accidents.

Research paper thumbnail of The Risks Related to the Interaction Between Natural Hazards and Technologies

Research paper thumbnail of Industrial accidents triggered by natural hazards: an emerging risk issue

Natural Hazards and Earth System Sciences, 2011

Research paper thumbnail of Industrial accidents triggered by earthquakes, floods and lightning: lessons learned from a database analysis

Natural Hazards, 2011

Natural hazards and disasters can cause major accidents in chemical and process installations. Th... more Natural hazards and disasters can cause major accidents in chemical and process installations. These so-called Natech accidents can result in hazardous-materials releases due to damage to process and storage units, or pipes. In order to understand the dynamics of Natech events, accidents triggered by earthquakes, floods and lightning recorded in industrial accident databases were analysed. This allowed the identification of the most vulnerable equipment types, their modes of failure due to natural-event impact and the final accident scenarios. Moreover, lessons learned for future accident prevention and mitigation were derived. The analysis showed that pipes and storage tanks are the most vulnerable equipment for earthquakes, floods and lightning, calling for more research of equipment behaviour under natural-event loading. The damage modes and states are strongly dependent on the characteristics of the impacting natural event. Toxic dispersion, fires and explosions were observed as a consequence of all three types of analysed natural events. In the case of floods, two additional scenarios were identified. These are water contamination and the formation of toxic and/or flammable vapours upon reaction of the released chemicals with the floodwaters. The overall number of recorded Natech accidents was found to range from 2 to 5% of all reported accidents in the analysed databases.

Research paper thumbnail of Risk Assessment of Major Accidents Triggered by Lightning Events

The analysis of major industrial accident databases indicates that lightning events are the most ... more The analysis of major industrial accident databases indicates that lightning events are the most frequent cause of technological accidents triggered by natural events in chemical and process plants. Severe fires, mainly affecting storage farms, are the most frequent final scenario associated to such events. In the present study, a quantitative methodology for the assessment of the risk due to major accidents triggered by lightning is presented. The methodology was developed within a common framework for the quantitative assessment of risk due to external hazard factors in chemical and process plants. The procedure also allows the identification of the credible scenarios that may be associated to the different modes of structural damage and the identification of critical equipment items.JRC.DG.G.7-Traceability and vulnerability assessmen

Research paper thumbnail of Assessment of the Probability of Structural Damage due to Lightning Impact on Process Equipment in the Chemical and Process Industry

A detailed analysis of past accidents evidenced that lightning strikes on storage or process vess... more A detailed analysis of past accidents evidenced that lightning strikes on storage or process vessels containing flammable materials may cause severe accidents at refineries, storage sites, processing sites and other industrial facilities where hazardous materials are stored or processed. Although the hazard due to lightning is well known and is usually considered in the safety analysis of chemical and process plants, well accepted quantitative procedures to assess the contribution of accidents triggered by lightning to industrial risk are still lacking. In particular, the approaches to the assessment of lightning strike probability, damage caused by lightning strike and intensity of loss of containment (LOC) caused by lightning are mostly based on expert judgment and not on up-to-date models that take into account the relevant progress made in the last years in the analysis of the lightning phenomenon. In the present paper an innovative procedure for the quantitative assessment of the industrial risk due to LOC of hazardous substances triggered by lightning is introduced. The study was focused on the development of models for lightning impact probability and for damage probability. In particular, a Monte Carlo approach was developed to calculate the probability of lightning impact on the basis of the geometry of the structure and of lightning intensity and frequency data.JRC.DG.G.7-Traceability and vulnerability assessmen

Research paper thumbnail of A novel framework for the quantitative assessment of risk due to major accidents triggered by lightning

Research paper thumbnail of Assessment of major accidents triggered by lightning

CRC Press eBooks, Aug 25, 2009

The present study aimed at the analysis of past accidents caused by lightning and the development... more The present study aimed at the analysis of past accidents caused by lightning and the development of a framework for the quantitative assessment of these events. The analysis of past accidents suggests that lightning events are the most frequent cause of technological accidents in chemical and process plants. Fires, mainly affecting storage farms and involving atmospheric storage tanks, are the most frequent final scenario associated to such events. The development of a quantitative methodology for the assessment of the risk due to major accidents triggered by lightning was thus addressed. The starting point of the methodology is the assessment of the frequency and severity of the lightning event. Different damage states were defined, and damage probability functions were derived. The overall frequency and intensity of loss of containment were thus determined. Standard models for consequence analysis allowed the assessment of the physical effects of the final scenarios.JRC.G.7-Traceability and vulnerability assessmen

Research paper thumbnail of Iclp 2010 Monte Carlo Based Lightning Risk Assessment in Oil Plant Tank Farms

Research paper thumbnail of Acceptability parameters for industrial risk with respect to natural-technological interactions

When industrial risks are of concern, local operators, safety management and public authorities a... more When industrial risks are of concern, local operators, safety management and public authorities are generally focused on technological risk sources, management deficiencies or human errors, but are often unaware of possible accidental scenarios which may derive from the impact of disastrous natural events as earthquakes, flooding or lightning on industrial establishments (Na-Tech hazard). This issue has been recently recognized by the European Community, which has financed a large-scale integrated project within the Seventh Framework Program, concerning the early recognition, monitoring and integrated management of risks related to emerging and new technologies (iNTeg-Risk). In the project, a specific task has been devoted to assess the contributions of Na-Tech risks to the overall industrial risk at community level, aiming at the improvement of the resilience of industrial facilities to technological accidents triggered by natural hazards. In the following, a general procedure for the evaluation of Na-Tech risks having considered floods, lightning and earthquakes, with specific reference to large scale equipment containing hazardous substances, is presented. Preliminary results of specific methods developed for the Quantitative Risk Assessment of industrial facilities and areas exposed to Na-Tech events are discussed. These results have clarified that the contribution of natural events to the industrial risks may be important and comparable to the purely technological risks. Furthermore, they allow the definition of priorities for the prevention and mitigation of accidental scenarios in terms of safety management, early warning systems and/or technological resources. The study also focused on the acceptability criteria for industrial installations with respect to the accidental events triggered by natural events. Important differences may arise if a classical reference for the acceptability matrix (e.g. the ALARP matrix) is used. The natural event recurrence period and the probability of its intensity and the hazard of top events require very different procedures for their estimation. Historical data are essential for natural events whereas they are less significant for industrial equipment, due to the continuous development of safety system and technology. Moreover, the figure for \u201cfrequent event\u201d in the industrial risk matrix has a correspondent \u201cvery rare\u201d figure for natural event in the geophysical or meteorological meaning, and the external environment is generally struggling for the natural event and overloading of public emergency systems does not allow a contribution for the industrial accidental scenario mitigation. Also, combined scenario occur when natural events strike any industrial installation, and mitigation systems are often affected at the same time, whereas single, partially mitigable scenarios are generally predicted in the normal process life and industrial safety assessment. Finally, the natural event effects may contribute to the overall risks as workers may be injured directly for the same event of for the structural damage of buildings, offices and steel structures inside the installation. In this framework, the possible definition of acceptability parameters based on threshold values for the natural events, either in terms of Na-Tech accidental scenario probability of occurrence or for the relative intensity was investigated. The proposed threshold values were obtained from the threshold values of the specific equipment categories, for each natural event, that were obtained in previous studies and from the analysis of the societal risk variation as obtained from QRA analysis

Research paper thumbnail of Monte Carlo based lightning risk assessment in oil plant tank farms

2010 30th International Conference on Lightning Protection (ICLP), 2010

Research paper thumbnail of Awareness and mitigation of NaTech accidents: Toward a methodology for risk assessment

Natural hazards affecting chemical and process facilities deserve particular attention since they... more Natural hazards affecting chemical and process facilities deserve particular attention since they can cause the release of hazardous substances possibly resulting in severe environmental pollution, explosions and/or fires (so-called NaTech accidents). Awareness of the hazard posed by Natech events in growing, and a need for explicitly including NaTech accidents into chemical-accident prevention and mitigation is nowadays widely recognized. Nevertheless, several elements that characterize Natech events still need to be investigated. In particular, only scarce data exists on equipment damage modes, release intensities and the final consequences for these accidents. The present contribution focuses on the development of a general framework for the assessment of NaTech risk. The analysis of past accident data allowed the gathering of data on the expected damage of process equipment caused by the impact of flood, lightning and earthquake events. Failure modes and damage states caused by ...

Research paper thumbnail of Equipment Failure Probability due to the Impact of Lightning

The historical analysis of accidental scenarios triggered by lightning shows that the impact of a... more The historical analysis of accidental scenarios triggered by lightning shows that the impact of a lightning on a process plant might be the initiating event of a severe accident. The analysis identifies the most common damages to the equipment as either immediate ignition of flammable atmospheres or structural damage with subsequent release. However, the available information on lighting damage to industrial equipment is fragmented and not very detailed. The aim of the present study is to define a failure model for reference equipment categories following lightning impact. Starting from the analysis of lightning damage, the possibility of equipment damage is assessed on the basis of lightning characteristics. The probability of failure is evaluated as the probability to find, in impacting lightning strikes, the minimum energy necessary to cause the loss of containment of the selected equipment. Probability distribution functions available for lightning characteristics, used together...

Research paper thumbnail of An Approach to the Quantitative Assessment of Risk Due to Natech Events

Transactions of the VSB - Technical University of Ostrava, Safety Engineering Series, 2012

Research paper thumbnail of Assessment of major accidents triggered by lightning

Theory and Applications, 2009

The present study aimed at the analysis of past accidents caused by lightning and the development... more The present study aimed at the analysis of past accidents caused by lightning and the development of a framework for the quantitative assessment of these events. The analysis of past accidents suggests that lightning events are the most frequent cause of technological accidents in chemical and process plants. Fires, mainly affecting storage farms and involving atmospheric storage tanks, are the most frequent final scenario associated to such events. The development of a quantitative methodology for the assessment of the risk due to major accidents triggered by lightning was thus addressed. The starting point of the methodology is the assessment of the frequency and severity of the lightning event. Different damage states were defined, and damage probability functions were derived. The overall frequency and intensity of loss of containment were thus determined. Standard models for consequence analysis allowed the assessment of the physical effects of the final scenarios.JRC.G.7-Traceability and vulnerability assessmen

Research paper thumbnail of Industrial accidents triggered by flood events: Analysis of past accidents

Journal of Hazardous Materials, 2010

Research paper thumbnail of Industrial accidents triggered by lightning

Journal of Hazardous Materials, 2010

Natural disasters can cause major accidents in chemical facilities where they can lead to the rel... more Natural disasters can cause major accidents in chemical facilities where they can lead to the release of hazardous materials which in turn can result in fires, explosions or toxic dispersion. Lightning strikes are the most frequent cause of major accidents triggered by natural events. In order to contribute towards the development of a quantitative approach for assessing lightning risk at industrial facilities, lightning-triggered accident case histories were retrieved from the major industrial accident databases and analysed to extract information on types of vulnerable equipment, failure dynamics and damage states, as well as on the final consequences of the event. The most vulnerable category of equipment is storage tanks. Lightning damage is incurred by immediate ignition, electrical and electronic systems failure or structural damage with subsequent release. Toxic releases and tank fires tend to be the most common scenarios associated with lightning strikes. Oil, diesel and gasoline are the substances most frequently released during lightning-triggered Natech accidents.

Research paper thumbnail of The Risks Related to the Interaction Between Natural Hazards and Technologies

Research paper thumbnail of Industrial accidents triggered by natural hazards: an emerging risk issue

Natural Hazards and Earth System Sciences, 2011

Research paper thumbnail of Industrial accidents triggered by earthquakes, floods and lightning: lessons learned from a database analysis

Natural Hazards, 2011

Natural hazards and disasters can cause major accidents in chemical and process installations. Th... more Natural hazards and disasters can cause major accidents in chemical and process installations. These so-called Natech accidents can result in hazardous-materials releases due to damage to process and storage units, or pipes. In order to understand the dynamics of Natech events, accidents triggered by earthquakes, floods and lightning recorded in industrial accident databases were analysed. This allowed the identification of the most vulnerable equipment types, their modes of failure due to natural-event impact and the final accident scenarios. Moreover, lessons learned for future accident prevention and mitigation were derived. The analysis showed that pipes and storage tanks are the most vulnerable equipment for earthquakes, floods and lightning, calling for more research of equipment behaviour under natural-event loading. The damage modes and states are strongly dependent on the characteristics of the impacting natural event. Toxic dispersion, fires and explosions were observed as a consequence of all three types of analysed natural events. In the case of floods, two additional scenarios were identified. These are water contamination and the formation of toxic and/or flammable vapours upon reaction of the released chemicals with the floodwaters. The overall number of recorded Natech accidents was found to range from 2 to 5% of all reported accidents in the analysed databases.