A Grid Based Approach for Fire and Explosion Consequence Analysis

The process area of an offshore oil and gas platform is very compact with a high degree of congestion and confinement due to space limitations and environmental conditions. Although there are safety systems installed on the platforms, the process area is never completely safe. Among the loss producing events, fires and explosions are the most frequently reported process related accidents. They have potential to cause serious injury to personnel, major damage to equipment and structure, and disruption of operations. It is therefore necessary to perform a fire and explosion hazard analysis as a basis for the implementation of appropriate mitigation measures and emergency response plans to protect personnel.In this paper, we reviewed the existing consequence models, such as source models, dispersion models, ignition models, fire and explosion models, and selected the ones most suitable for offshore conditions. These models were then used to perform a consequence assessment for an offshore platform by simulating four different scenarios. Two main revisions were incorporated: (1) a grid-based approach was adopted to enable better consequence/impact modelling and analysis of radiation and blast overpressures, and (2) an enhanced onsite ignition model was integrated in the consequence assessment process to obtain better results.