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acceptance criteria; risk acceptability acceptance criteria 34, 39, 113, 115-116, 119, 161 see also acceptability criteria; risk acceptability accidents estimation of physical effects 249-250 major 143, 243, 245-246, 266 resulting from vapour cloud explosion 79 see also industrial accidents active fire protection (AFP) 13, 137, 145, 180, 219

Fire risk assessment is a fundamental element of the entire organisation divided into its process (main ones and auxiliary ones), and it needs special attention including the aspects associated with the incoming elements and the findings to be made available for informed decisions. As ISO 31000 outlines the principles and guidelines for risk management, the associated IEC/ISO 31010 technical standard reviews some techniques to be used for risk assessment. The focus, therefore, is on the phase of the risk-management process that aims to answer the following questions: What can happen and why (risk identification phase)? What are the consequences and probabilities of the hypothesised events and what are the factors that mitigate their severity or reduce their probability (risk analysis phase)? What is the final risk level in relation to the tolerability and acceptability thresholds used (risk evaluation phase)?

This book allows the readers achieving a common and intuitive overview of the process to select, design and operate a fire strategy in a risk-based framework, in which the strategy, as a pool of different measures, is not unique. Resilience is achieved when fire risk assessment allows the consideration of the relevant fire scenarios, and their mitigation in frequency and magnitude to an acceptable level, given a defined risk criterion, is put in place and maintained over the time with a sound fire-safety strategy, known and shared among the stakeholders. Stakeholders should be aware of, considering the fire strategy as a common and shared holistic approach that goes beyond the differences among the parties to a specific additional and inalienable objective for the building performance, fire safety.

Risk management is therefore an integral part of all organisational processes and decision making. It should be systematic, structured and well timed. It should also be based on the best available information and well tailored. It should consider human and cultural factors (‘soft’ factors) together with technical and organisational factors (‘hard’ factors). Intuitively and understandably, fire risk is one of the risks that requires the most attention and the development of a robust strategy, maintained over time to ensure the safety of occupants, the environment, assets and business continuity.

Fire-safety design and fire-safety management over time are complex activities that require the knowledge and awareness of the stakeholders about the fire scenarios that may arise and develop according to the fire threats associated with their assets. Each application context is characterised by clearly different fire risks, associated with a series of peculiarities of the domain of interest which find their expression in the development of more or less complex scenarios as well as being determined, in their evolution, by the strategy adopted and its partial/complete success. Fire and explosion scenarios in the civil construction sector are particularly different from those observed in the industrial sector, especially in the presence of hazardous substances. In the industrial sphere, the same severity can lead to major accidents in many countries regulated by specific regulations. In Chapter Unavailable , an attempt is made to briefly illustrate the types of accident scenarios in the industrial and civil sectors.

In full compliance with risk-management approaches, lessons learnt from real events (both accidents and incidents as well as near misses and anomalies) are a fundamental way to increase fire safety and mitigate the reoccurrence. This activity is not only supported by the information and knowledge sharing activity but also by the methods available to conduct the analysis of real events. Some of them are very structured and standardised. Some of the anticipated cases are assessed to identify the main failures that led or escalated to a fire event in different sectors ranging from the maritime industry to heritage buildings. The use of the Fire-safety Concept Tree is also shown as a method to allocate the observed failures to the main elements of a fire-safety strategy with an obvious advantage in the identification of corrective actions for new projects.