Industrial accidents triggered by natural hazards: an emerging risk issue

Abstract. The threat of natural hazards impacting chemical facilities and infrastructures with the subsequent release of hazardous substances has been recognised as an emerging risk which is likely to be exacerbated by the ongoing climate change. Within the European FP7 project iNTeg-Risk, efforts are dedicated to address the problem of Natech accidents by trying to understand their underlying causes and by developing methodologies and tools to assess Natech risk. Special attention is thereby given to the risk of chemical accidents triggered by earthquakes, floods and lightning. This work outlines the ongoing efforts in the development of new concepts and tools for Natech hazard and vulnerability ranking, risk assessment, risk-based design, and emergency planning and early warning

Industrial accidents triggered by natural hazards: an emerging risk issue

The threat of natural hazards impacting chemical facilities and infrastructures with the subsequent release of hazardous substances has been recognised as an emerging risk which is likely to be exacerbated by the ongoing climate change. Within the European FP7 project iNTeg-Risk, efforts are dedicated to address the problem of Natech accidents by trying to understand their underlying causes and by developing methodologies and tools to assess Natech risk. Special attention is thereby given to the risk of chemical accidents triggered by earthquakes, floods and lightning. This work outlines the ongoing efforts in the development of new concepts and tools for Natech hazard and vulnerability ranking, risk assessment, risk-based design, and emergency planning and early warning

Analysis of the impact of wildland-urban-interface fires on LPG domestic tanks

Managing Wildland-Urban-Interface (WUI) fires is a challenging task due to the inherent complexity of the WUI environment. To ensure the success of strategies for the protection of population and structures, safety measures have to be implemented at different scales (landscape, community and homeowner). The present study is focused on the homeowner scale and deals with the threat related to the presence of LPG domestic tanks in a WUI fire scenario. Recent accidents have demonstrated that the risk associated with this type of installation is real, but often disregarded by residents. A methodology was developed, providing a set of indicators that may easily be compared with risk acceptance criteria, assessing whether the integrity of an LPG tank exposed to WUI fire scenarios is compromised or not. The methodology is applicable to a vast range of situations and at a different level of detail according to available data. A number of case studies were carried out, showing that WUI fire scenarios impacting on domestic LPG tanks complying with regulations currently adopted in several Mediterranean countries cannot be deemed safe. The methodology proposed represents an advanced tool to assist on safety distances sizing to be prescribed by standards, driving regulators towards better-informed decision-making

Domino effects related to explosions in the framework of land use planning

The present study analyses the possible escalation due to the damage of industrial equipment containing hazardous materials loaded by pressure waves produced either by an accidental source as a Vapour Cloud Explosion, or by a voluntary external attack such as the explosion of a TNT charge located nearby the industrial facility. The results obtained evidence the similarities and the differences for the two explosion sources in terms of structural damage, loss of containment and of expected impacts on the population. In particular, a specific vulnerability assessment was carried out defining a case-study in order to evidence the different potential impact of domino effect triggered by internal process causes respect to escalation scenarios caused by external acts of interference. © 2013, AIDIC Servizi S.r.l

Controlled targeting of different subcellular sites by porphyrins in tumour-bearing mice.

Unilamellar liposomes of dipalmitoyl-phosphatidylcholine can incorporate various porphyrins in either the phospholipid bilayer or the internal aqueous compartment depending on the water-/lipo-solubility of the drug. Intraperitoneal injection of the liposome-bound porphyrins to mice bearing a MS-2 fibrosarcoma results in remarkably more efficient tumour targeting than that obtained by administration of the same porphyrins dissolved in homogeneous aqueous solution. Moreover, also water-insoluble porphyrins can be transported to the tumour via liposomes. Fractionation of liver and neoplastic cells indicates that the subcellular distribution of liposome-delivered porphyrins is also dependent on their solubility properties: thus, relatively polar porphyrins, such as tetra(4-sulfonatophenyl)porphine and uroporphyrin, are mainly recovered from the soluble fraction, whereas hydrophobic porphyrins, such as haematoporphyrin or porphyrin esters, preferentially partition in the cytoplasmic membrane. As a consequence, different subcellular sites can be targeted by porphyrins and possibly photodamaged through a suitable choice of the drug-carrier system

Assessment of Failure Frequencies of Pipelines in Natech Events Triggered by Earthquakes

During a seismic event, underground pipelines can undergo to significant damages with severe implications in terms of life safety and economic impact. This type of scenarios falls under the definition of Natech. In recent years, quantitative risk analysis became a pivotal tool to assess and manage Natech risk. Among the tools required to perform the quantitative assessment of Natech risk, vulnerability models are required to characterize equipment damages from natural events. This contribution is focused on the review of the pipeline vulnerability models available for the case of earthquakes. Two main categories of models have been identified in the literature. A first category proposes the repair rate as performance indicator for the damage of pipeline due to seismic load, and gives as output the number of required repairs per unit length. A second category proposes fragility curves associated with risk states depending on the mechanism of ground failure. In the framework of Natech risk assessment, the latter have the important advantage of having clearly and unambiguously defined the risk status (and thus the extent of the release) with which they are associated. A subset of vulnerability models deemed more appropriate to be applied in the framework of Natech risk assessment is then identified. Their application to the assessment of the expected frequencies of release events due to pipeline damage is provided, enabling their comparison and the discussion of the relative strengths and weaknesses

Lumped model for the assessment of the thermal and mechanical response of LNG tanks exposed to fire

Fires may impact on liquefied natural gas (LNG) process and storage units causing severe damages and potential accident escalation. In the present work, a lumped model able to predict the thermal response of LNG tanks exposed to fire is presented. The model is based on a thermal nodes approach, solving heat and material balances on the equipment exposed to fire, contemplating boiling regime phenomena, heat-up and pressure build up. The model allowed obtaining key indications for the evaluation of the vessel resistance during fire exposure. The model was applied to reproduce the accident scenario occurred at Tivissa (Spain) in 2002 and applied to an industrial case study

Kinetic Generation of Whistler Waves in the Turbulent Magnetosheath

The Earth's magnetosheath (MSH) is governed by numerous physical processes which shape the particle velocity distributions and contribute to the heating of the plasma. Among them are whistler waves which can interact with electrons. We investigate whistler waves detected in the quasi-parallel MSH by NASA's Magnetospheric Multiscale mission. We find that the whistler waves occur even in regions that are predicted stable to wave growth by electron temperature anisotropy. Whistlers are observed in ion-scale magnetic minima and are associated with electrons having butterfly-shaped pitch-angle distributions. We investigate in detail one example and, with the support of modeling by the linear numerical dispersion solver Waves in Homogeneous, Anisotropic, Multicomponent Plasmas, we demonstrate that the butterfly distribution is unstable to the observed whistler waves. We conclude that the observed waves are generated locally. The result emphasizes the importance of considering complete 3D particle distribution functions, and not only the temperature anisotropy, when studying plasma wave instabilities.Peer reviewe

New insights into the pathogenesis of bullous pemphigoid: 2019 update

There are several lines of evidence indicating that the physiopathological bases of bullous pemphigoid (BP), the most common subepidermal autoimmune bullous disease, are hallmarked by the production of autoantibodies directed against the hemidesmosomal anchoring proteins BP180 and BP230. In contrast to the robustness of the latter assumption, the multifaceted complexity of upstream and downstream mechanisms implied in the pathogenesis of BP remains an area of intense speculation. So far, an imbalance between T regulatory cells and autoreactive T helper (Th) cells has been regarded as the main pathogenic factor triggering the autoimmune response in BP patients. However, the contributory role of signaling pathways fostering the B cell stimulation, such as Toll-like receptor activation, as well as that of ancillary inflammatory mechanisms responsible for blister formation, such as Th17 axis stimulation and the activation of the coagulation cascade, are still a matter of debate. In the same way, the pathomechanisms implied in the loss of dermal-epidermal adhesion secondary to autoantibodies binding are not fully understood. Herein, we review in detail the current concepts and controversies on the complex pathogenesis of BP, shedding light on the most recent theories emerging from the literature

Accident scenarios caused by lightning impact on atmospheric storage tanks

In recent years, severe natural events raised the concern for the so-called NaTech (natural-technological) accident scenarios: Technological accidents caused by the impact of a natural event on an industrial facility or infrastructure. Severe scenarios typical of the process industry, as fires, explosions, toxic releases, and water pollution were reported as the consequence of natural events in industrial areas. The historical analysis of accidental scenarios triggered by lightning shows that the impact of a lightning on an atmospheric storage tank might be the initiating event of a severe accident. The analysis of past accident evidences that several alternative damage mechanisms and accident scenarios may follow lightning impact. Although lightning hazard is well known and is usually considered in the risk 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 accident scenarios following lightning strike are mostly based on expert judgment. In the present study, a detailed methodology is presented for the assessment of quantified event trees following lightning impact on an atmospheric tank. Different damage mechanisms have been considered in order to assess the frequencies of loss of containment due to lightning strikes. The results were used in a case study to assess the overall risk due to lightning impact scenarios in typical lay-outs of tank farms of oil refineries. Copyright © 2013, AIDIC Servizi S.r.l