R. Pastorino

A framework for risk assessment and decision-making strategies in dangerous good transportation

The risk from dangerous goods transport by road and strategies for selecting road load/routes are faced in this paper, by developing an original site-oriented framework of general applicability at local level. A realistic evaluation of the frequency must take into account on one side inherent factors (e.g. tunnels, rail bridges, bend radii, slope, characteristics of neighborhood, etc.) on the other side factors correlated to the traffic conditions (e.g. dangerous goods trucks, etc.). Field data were collected on the selected highway, by systematic investigation, providing input data for a database reporting tendencies and intrinsic parameter/site-oriented statistics. The developed technique was applied to a pilot area, considering both the individual risk and societal risk and making reference to flammable and explosive scenarios. In this way, a risk assessment, sensitive to route features and population exposed, is proposed, so that the overall uncertainties in risk analysis can be lowered.

A century of accidents in the Italian industry: Relationship with the production cycle

Abstract The purpose of this paper is to examine the fluctuations of accident frequency in the Italian industry during a period of time covering almost a hundred years (from 1890 to 1989) and to examine possible connections with industrial production fluctuations. Notwithstanding the considerable variations of economic and social conditions and the increasing technological and scientific improvement, the number of accidents never drops below 110 cases per 1000 workers/year. We focused our attention on economic factors, which, especially over the long run, seem to be the most important, so as to set the basic trends in occupational accidents. A nice parallelism between the economic cycle and the trend of accidents has been pointed out, differences not exceeding 20% over the whole period of observations. This relationship affords the oppurtinity to verify that the factors influencing human safety conditions in industrial activities do not depend on technological development.

An Approach to Risk Evaluation in Connection with Fire Scenarios from a Cruise Ship

The main threat from ship accidents is connected to the transport of chemical/petrochemical products and possible environmental impact from leakages. However, in case of sensitive environmental targets, a serious threat can be represented by cruise ship too, as demonstrated by Costa Concordia, a perfect example of a modern cruise ship that capsized in 2012, under calm sea and clear visibility conditions near the shore of Giglio Isle, Italy. This paper approaches cruise risk assessment in a vulnerable area located about 25 km East of Genoa with 13 km of coastline into the Ligurian gulf. The framework allows the attainment of cautious values of the maximum affected and hazardous areas, in connection with fire scenarios and smoke spreading. The conservative results are to be considered in setting-up emergency planning with appropriate response equipment, fire-fighting and lightering resources and can be a powerful tool to design optimal ship route and temporary docking points for cruise tourism, thereby balancing economic issues and inherent safety criteria.

Oil spills: from statistical analysis to quantitative risk assessment

This paper is focused on the development of a formalised approach to the quantification of risk in probabilistic terms, according to the methods already appIied in the process industry. The study is structured into linked stages that were undertaken sequentially, as follows, The first part was dedicated to the analysis of the long-term accident trends in open sea and to elaborate world-wide statistics on the number and frequency of spills, immediate and underlying causes, as well as on accident evolving scenarios. The statistics about the frequency of casualties can provide an overall view of the level of safety involved in the shipping activity, In facing the whole risk two aspects can be outlined: risk in open sea and risk in harbour area. Therefore, in the subsequent applicative phase, an Italian casestudy was considered, by developing a quantified risk assessment methodology. Starting from the elaboration of the collected yearly data on hydrocarbon transport and type of tankers in the considered port, it was possible to perform a statistical reinforced analysis of the expected accident frequency. A range of possible accident scenarios was selected, starting from the analysis of oil related activities and the type of hydrocarbon handled or transported in the area. The analysis of the consequences of the oil spill and the subsequent accident in case of ignition was performed considering, in detail, the study of the pool fwe and the connected thermal radiation. Based on these findings, conclusions are drawn, with emphasis on some risk control options and practical recommendations, according to inherent safety principles.

Risk assessment and decision-making strategies in dangerous good transport. From an Italian case-study to a general framework

Publisher Summary This paper discusses the risk associated with the transportation of dangerous goods by road and strategies for selecting road load/routes by developing a site-oriented framework of general applicability. A methodological approach for the assessment of standard vehicle and dangerous good truck flows was applied to a pilot area, allowing a statistical reinforced evaluation of intrinsic enhancing/mitigating parameters. In this way a risk assessment sensitive to route specifics and population exposed is proposed and the overall uncertainties by the risk analysis can be lowered. The developed model, of general applicability, can represent a useful tool not only to estimate transport risk but also to define strategies for the reduction of risk and emergency management. Poor appreciation of factors related to road conditions such as road class, designated speed limits, traffic density, as well as of the population characteristics, is likely to result in a risk assessment insensitive to route specifics and over- or under-estimating the overall level of risk. The results show that the risk associated with the transport of hazardous materials on the highway considered in the chapter is at the limit of the personally acceptable level of risk.

A methodological approach to internal antifire crew optimization. An oil refinery case history

This paper deals with the problem of defining the operational tasks, modelling and optimizing of antifire crew and their attempts. Unwanted events are generally modest and easily controlled in their starting phase. This obviously leads to considering that quickness and coordination enhance the possibility of successful fire control. Hence the importance that the first intervention of the factory antifire crew is supported by strong organization and efficiency. Immediate and appropriate response to emergency is essential to minimize severity of accidents, life losses, as well as the potential reduction in the plant future productivity. In approaching internal antifire crew optimization, it is convenient to distinguish a traditional inventory phase, a subsequent optimization and a graphic modelling phase. Optimization criterion is developed according to graph theory, with regard to intervention pathways and to consistency of antifire crew. The proposed graphic model provides, in an immediately readable way, the sequence of operator actions to be followed in order to cope with emergency situations.

An innovative unified model for the rate of air mixing with releases from high velocity sources

Publisher Summary The evaluation of the rate of air mixing with a sudden release of flammable or toxic material is an essential tool for properly designing flares, vents, and other safety devices, as well as to quantify the potential risk connected to the existing ones or arising from the various kinds of accidents that can happen in process industries. An iterative procedure was developed for the evaluation of the boundaries of the cloud flammable region, making use of the experimental data obtained in wind tunnel. It was showed that a significant subset of this data can be correlated to describe the boundaries of the flammable cloud by means of a simple formula. In addition, it was also demonstrated that a similar approach can be applied to the whole set of the data, resulting in a more general mathematical description of the jet dispersion, applicable to face easily the different kinds of design problems concerning upward directed releases with much more ease. The model, validated by means of replicated tunnel experiments, substantially agrees with the existing ones for the limiting cases of horizontal and upward directed jets. The model directly gives the boundaries of flammable clouds and the ground level concentrations of toxic releases; in addition, with some modifications, it can be applied to evaluate the heat transfer on vessels and buildings due to flame radiation and impingement.

T9-17 – A combined approach to improve safety performance on existing process plants. Practical application according to Seveso II

Publisher Summary Seveso II Directive (96/82/EC), dealing with the control of major accidents and acknowledged by Italian law D.L. 334/99, implies the need of developing adequate tools for the evaluation and mitigation of industrial risk. Retrospective Hazop is considered suitable for safety assurance, but it is rejected because it suffers from limitations and involves considerable time. The technique has been developed ad hoc starting from Hazop and Process Hazard Review and applied to a process of acrylic polymerization along the whole production cycle. The process of Hazop is well known as an effective and highly respected method of hazard identification. The Hazop is applied only to those sections of a plant where it has been determined that a deviation from the design intent could lead to serious accidents; it suggests the action required to reduce the risk of accidents. The evaluation of a risk by the Index Method allows a univocal interpretation of the hazards of an existing plant, related to the intrinsic characteristics, the chemistry, and the environmental conditions, allowing to characterize every unit by a global risk index. On the other side, the technique attempts to overcome Hazop limitations for existing plants, taking into account all the interventions and modifications to plant design, by the use of experience, current best practice, and actual tendency towards inherent safety plants.