A risk assessment model for oil and gas industry operations

Abstract

The study presented in this thesis tackles a risk assessment model for oil and gas industry operations, mainly based on a bow-tie risk assessment. The oil and gas industry, specifically the pipeline transportation sector, is continually vulnerable to high risk levels, and the risk of pipeline failure and the release of carried products can result in grave environmental consequences and damage. The methodology employed in quantifying related risks levels rely primarily on event tree analysis, fault tree analysis, and bow-tie model. These tools are applied to a typical natural gas pipeline system. The top event was chosen to be ‘pipeline leakage’ and the corresponding bow-tie model was graphed. The potential causes in the fault tree were divided into two categories: process failure which includes corrosion failure, material defects, and equipment or welding failure, and non-process failure which covers excavation and earthworks and outside force damage. The event tree concluded in three possible outcomes: safe prevention, unsafe prevention, and no prevention. Results show clear mapping of the causes and consequences for a certain hazardous event, and once risks are identified, risk ranking of the hazardous outcomes of a chemical cleaning incident is performed, and decision-making at the planning stage can be improved and more suitable control and recovery measures can be put in place.