Abstract
A major fire is a credible scenario for any site or installation that is involved in the storage of liquid hydrocarbons (oil and fuels). Similarly, a major explosion scenario (albeit less probable than a major fire scenario with respect to hydrocarbons storage) could be considered for bulk hydrocarbon storage sites if the lessons of Buncefield explosion in 2005 are put in perspective.
Obviously, major incidents like oil/fuels storage tank fires and explosions do not occur frequently; nevertheless the associated risks are ever present with attendant high impacts on people, assets and environment. Dealing effectively with these types of hazards would require a well-structured and verifiable fire hazard management (FHM) approach on one hand, and satisfactory level of emergency response preparedness on the other hand. A realistic FHM approach spanning prevention and control/mitigation measures when combined with good level of incident response preparedness (with respect to men, equipment and materials) would facilitate the reduction of associated oil storage tank fire risks to ALARP level.
Historically, the success rate of suppression and extinguishment for full surface oil tank fires is relatively low, particularly for larger tanks with diameters greater than 30 m. The only known large tank fire ever extinguished was the Orion refinery tank fire (circa 82 m diameter) in 2001. Suppressing oil tank fires is no simple task, and failures to achieve suppression timely are due to many factors most of which could have been addressed with suitable risk perception, evaluation, education and management. Poor risk perception could blindside operator’s site or corporate management to the extent that oil tank fire incident may be considered as very remote possibility or to assume that the provision of fixed and portable fire systems and a fire brigade are enough risk controls for oil tank fires. Managers of hydrocarbons bulk storage facilities need to be educated on the scale of oil tank fire hazards including but not limited to tank rupture/collapse, explosion, and boil over, and the associated challenges and competencies required to manage industrial catastrophic events of such magnitude.
This paper is therefore set to highlight the scale of threat posed to people, assets, business continuity and the environment by hydrocarbon storage tank fires, and discuss the main tank fire hazards and key factors that influence the success or failure in the prevention and suppression of oil storage tank
