Loss scenarios

The safety and risk of a hydrocarbon facility cannot be assessed solely on the basis of fire fighting systems or past loss histories. The overall risk can only be assessed by defining loss scenarios and an understanding of the risk philosophy adopted by senior management. 

The goal of assessing risk is to build on the knowledge of chemical reactivity hazards, to understand how the hazard properties may lead to loss scenarios in the facility context, and to determine whether existing safeguards are adequate. Therefore, the assessment of risk can be performed at any stage of facility design, development, operation, or alteration. Of course, the more that is known about the facility and its equipment and operation, the more detailed the risk assessment can be. Methods used to determine chemical reaction risks are varied, as are their objectives and data requirements. 

The design and construction of a chemical warehouse should consider possible loss scenarios that may affect employees, the surrounding population, the environment, the warehouse building and business continuity. Protection and mitigation features should be consistent with the characteristics of the materials stored, environmental and population vulnerability, and potential natural perils. 

Potential loss scenarios include fire, explosion, chemical release, natural peril occurrences, riot and civil commotion, arson, loss of utilities, or a fire, explosion, or a chemical release at a nearby facility. Chemical releases might result from a spill or container failure, or as a consequence of fire, natural peril, or other event, and might involve the chemicals themselves, products of chemical reactions or decomposition, or in the case of fire, products of combustion. 

The possible loss scenarios, including events originating both internally and externally, should be explored. An assessment should then be made of the controls and protection features provided and their mitiga-tive effect on each loss scenario. Failures of controls and protection features should then be assumed to determine the worst-case and other, more credible, loss scenarios. Finally, the likelihood and degree of risk associated with each loss scenario should be developed. 

A timely and effective response will be necessary to mitigate the effects of worst-case and other, more credible, loss scenarios. 

Based upon the loss scenarios defined, the plan should prescribe the manpower and equipment resources needed as outlined in Section 9.6. 

Step 4 Calculate Tranche Loss Scenarios. Calculate the probability of each loss scenario for each tranche using a binomial distribution. Calculate the amount of loss for each tranche in each scenario. 

The safety manager should develop multiple approaches to deal with organizational risk. Analysis of the risk assessment process is often enhanced by developing various models and techniques from various loss scenarios. The utilization of differing approaches is based on assumptions regarding how potential risks materialize... 

Kappos AJ, Panagopoulos G, Penelis GG (2008) Development of a seismic damage and loss scenario for con-tempraary and historical buildings in Thessaloniki, Greece. Soil Dyn Earthq Eng 28(10-11) 836-850... 

The seminal paper by Haimes and Jiang (2001) introduces the initial EM framework, wherein a linear model analogous to I-O systems is proposed to compute the propagation of inoperability through interdependent physical infrastructure. Subsequent woik by Santos and Haimes (2004) shows how IIM model parameters can be calibrated from economic I-O data, using the demand-reduction interpretation of inoperability. The concept of forced demand reduction was later introduced to model supply loss scenarios within the IIM framework (Anderson et al. 2007). For an introduction to interval arithmetic, the reader may refer to the book by Kaufmann and Gupta (1985), while its application within IIM is demonstrated in the work of Barker and Rocco (2011). 

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