Probabilistic Hydrocarbon Release Leading to Fire and Explosion Incorporating System and Human Reliability Analysis: A Comparison of Onshore and Offshore Facilities

Human support and the inevitable interaction necessarily play a major part in daily production and maintenance activities at onshore and offshore facilities.The impact of human reliability on performance of workers at offshore facility is higher compared to onshore facility, owing to the harsh offshore working environment.This study presents an integrated probability model that combines human and system reliabilities and utilises a Bayesian network (BN).A comparison was made between onshore and offshore facilities in terms of human reliability and probability of hydrocarbon release leading to fire and explosion in order to investigate the influence of human performance shaping factors (PSFs) of human error at each working environment.Particularly, this research uses probability values obtained from expert opinions in fire and explosion scenarios caused by hydrocarbon release in onshore and offshore facilities.The proposed integrated approach is applied to a case study on hydrocarbon storage tank at onshore and offshore facilities.Accordingly, three possible consequences were evaluated (i.e., probability of safe condition, hydrocarbon release and high pressure) that could lead to fire and explosion.The probabilities of consequences are compared between onshore and offshore working conditions.It has been observed that the probability of hydrocarbon release of at onshore is slightly higher compared to offshore working environment with a percentage difference of 0.032 and this can be neglected due to the small difference.Meanwhile, the influence of PSFs of human error are higher at offshore working condition.Therefore, it can be concluded that there is a higher influence of human PSF of stress, task complexity, training, experience and atmospheric factor of human error at offshore compared to onshore due to the harsh working environment. © 2023, Institute of Technology PETRONAS Sdn Bhd.