GNGTS 2018 - 37° Convegno Nazionale

542 GNGTS 2018 S essione 2.3 Alternatively, a conservative choice for the intensity measure (e.g. PGA, PGV, PGD for earthquake) can be adopted by considering the threshold value for the structural damage and for release of content, as also suggested by Mulargia et al.. These methodologies are applied, for instance, when earthquake involves long oil or gas abo-ground or buried pipelines and fast response for the post-event survey is needed (Lanzano et al. , 2013; 2014; 2015). Technologicalhazardandvulnerability. When industrial installations are analysed, a technological hazard assessment is strongly needed because of the complexity of the system, in order to reduce the overall number of possible outcomes (the accidental scenarios). The procedure takes into account the industrial accidental scenarios as fire, explosion or large- scale dispersion of toxic substances. Hence, large release of content from the corresponding system of containment (i.e. the equipment: atmospheric storage tank, pressurised tanks, reactors, pumps, elongated vessels as separators) is needed. Eventually, only large equipment containing large amount of hazardous substance (as the EU classification, labelling and packaging – CLP - hazard classification normative) should be considered. For the given set of equipment, the fragility function should be then used for the evaluation of the probability of loss of containment (rather than structural fragility), given the intensity of the natural event. These functions are rare and should be considered as a main goal for the scientific and technology development in the next future Consequence assessment and risk re-composition. For the sake of comparability of studies, standard methods have been then developed in the Netherlands, to a large extent by TNO, through some reference handbooks, namely the Yellow Book, Green Book, Purple Book and Red Book (VROM, 2005a-d). The “coloured” books are public and may be considered de facto as a standard reference for any risk assessment. The reader can refer to them for further details on the standard industrial risk assessment. For the acceptability criteria, the work of Paté-Cornell (1994) may be also considered. Conclusions. In-depth analyses of Natech accident data often indicate inadequate design bases of hazardous installations in natural-hazard prone areas due to the use of generic design criteria, whereas the need for Natech- specific additional safety measures and a lack of Natech risk assessment contribute to low preparedness levels. Furthermore, a lack of guidance on how to evaluate Natech risks in the chemical process industry is clear. The needs of fragility functions for the industrial equipment related to the loss of containment rather than the structural integrity is strongly needed, together with reliable hazard assessment for the natural event. Acknowledgements. The study presented in this paper was developed within the activities of ReLUIS (Rete dei Laboratori Universitari di Ingegneria Sismica) for the project ReLUIS-DPC 2014–2018, Unit UNIBO 2 - Impianti. Fig. 1 - Flowchart of the Procedures for Quantitative Risk Assessment of Natech Scenarios as defined in Campedel et al. (2008).