Process Safety and Environmental Protection 9 0 ( 2 0 1 2 ) 424–429 Contents lists available at SciVerse ScienceDirect Process Safety and Environmental Protection jou rnal h om epage: www.elsevier.com/locate/psep Anatomy of a domino accident: Roots, triggers and lessons learnt Bahman Abdolhamidzadeh a,* , Che Rosmani Che Hassan a , Mahar Diana Hamid a , Sajjad FarrokhMehr a , Naser Badri b , Davood Rashtchian b a Department of Chemical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia b Centre for Process Design, Safety and Loss Prevention (CPSL), Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran a b s t r a c t On July 24th, 2010, several explosions and fires devastated a hydrocarbon processing plant in Kharg Island, Iran. Four workers were killed and many others were severely injured. The plant became out of service for 80 days. The way the accident happened and its sequence was representing as a domino accident. In this paper, events leading up to the disaster have been analyzed in details. Graphic presentation techniques such as Fish Bone Analysis and Event Sequence Diagram (ESD) have been utilized to enhance the understanding of the accident mechanism. Finally major lessons learnt from this domino accident have been addressed. © 2012 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. Keywords: Lessons learnt; Domino accident; Fish Bone Analysis; Event Sequence Diagram 1. Introduction Petrochemical complexes are major hazardous installations which process large quantities of different substances. Large amount of flammable substances, intense temperature and pressure conditions make these installations potential sources of severe accidents. Due to the complexity, congestion and level of interaction among subsystems in petrochem- ical plants, the accidents that usually have occurred were not standalone. There is a high potential of domino accident occurrence in those plants meaning an initial accident can triggers more and more accidents making the consequences worse (Khan and Abbasi, 1998, 1999a). The Middle East has probably the most important influence on the global petrochemical industry today and will remain so for many years to come. The region’s unparalleled produc- tion cost advantage and the willingness of its governments to diversify their oil-based economies have fostered expo- nential growth of this industry (Khoshrou, 2003). However, rapid growth of industry in this region had another undesir- able consequence; more accidents. A survey done by authors has shown that both the number and the fatalities of domino accidents are decreasing in developed countries while these * Corresponding author. Tel.: +60 173264892; fax: +60 379675319. E-mail address: abdolhamidzadeh@um.edu.my (B. Abdolhamidzadeh). Received 17 January 2012; Received in revised form 4 April 2012; Accepted 18 April 2012 statistics are rising globally. At the moment, the share of devel- oping countries from past domino accident is around 28% but it is growing year by year. That study has revealed that 12% of the total past domino accidents belongs to Middle East region (Abdolhamidzadeh et al., 2011). One of the lat- est domino accidents which has occurred in this region has taken place in Kharg Petrochemical plant. This plant is located in Kharg Island, 25 km off the coast of Iran and is producing mainly propane, butane and methanol. Similar to many past domino accidents, the material which has been involved in this accident was a mixture of propane and butane. Based on a comprehensive analysis of 225 domino accidents, LPG has the highest share (26.7%) among all the chemicals involved in past domino accidents (Darbra et al., 2010). Table 1 shows some of these accidents. Although the hazard associated with light hydrocarbons such as propane and butane has been repeatedly pointed out, there are still accidents happening with these components involved. It seems that in spite of the importance of these components, industry still needs lessons to be learnt in this regard. Some of these lessons can be learnt by reviewing past accident. So in this paper, Kharg accident has been selected for study and analysis. 0957-5820/$ – see front matter © 2012 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.psep.2012.04.003