The Event Sequence Diagram framework for dynamic Probabilistic Risk Assessment

Dynamic methodologies have become fairly established in academia. Their superiority over classical methods like Event Tree/Fault Tree techniques has been demonstrated. Despite this, dynamic methodologies have not enjoyed the support of the industry. One of the primary reasons for the lack of acceptance in the industry is that there is no easy way to qualitatively represent dynamic scenarios. This paper proposes to extend current Event Sequence Diagrams (ESDs) to allow modeling of dynamic situations. Under the proposed ESD representation, ESDs can be used in combination with dynamic methodology computational algorithms which will solve the underlying probabilistic dynamics equations. Once engineers are able to translate their knowledge of the system dynamics and accident evolution into simple ESDs, usage of dynamic methodologies will become more popular.