The Accident in Bhopal: Observations 20 Years Later

1. The Accident in Bhopal: Observations 20 Years Later Ronald J. Willey, Northeastern University, Boston, MA, r.willey@neu.edu Dennis C. Hendershot, Chilworth Technology Inc., Plainsboro, NJ, dhendershot@chilworth.com Scott Berger, CCPS Director, AIChE, New York, NY, scotb@aiche.org

2. Introduction The most influential process safety accident in our history passed its 20th anniversary on Dec 3, 2004 This accident occurred before most current college students were born Educators and the Process Safety Committee must keep the memory of this accident alive

3. A chemical plant in Bhopal, India producing a pesticide tradename Sevin So – What Happened?

4. Map of Bhopal

5. Bhopal Railroad Station 4 December 2004

6. Upper Lake Adjacent to the City

7. Plant Entrance Early 1985

9. AN INTERMEDIATE IN THE PROCESS METHYL ISOCYANATE, MIC CH3-N=C=O

10. Relevant Properties PROPERTIES of MIC BOILING POINT 39.1°C VAPOR PRESS AT 20°C 348 mm HG MOLECULAR WEIGHT 57 VAPOR DENSITY (Rel to Air) 2

11. METHYL ISOCYANATEMIC IS AN EXTREME TOXIN HAS A TLV-TWA OF 0.02 PPM (ONE OF THE LOWEST!) LC50 of 5 PPM FOR RATS

12. Storage of MIC Stored three-41 ton storage tanks. One of these tanks became contaminated with water resulting in overheating A runaway reaction

13. Overview Visual of the Storage Tanks

14. Tank 610 Over Pressurized

15. Piping at the Top of a Storage Tank

16. Relief Valve Opened as Designed

17. Downstream Relief System

18. The release passed across a scrubber as designed The release passed through a flare tower as designed

19. Unfortunately, neither of these mitigating units were operating at the time of the release One of the largest man-made releases of a toxin followed

20. Escaping Gas Blanketed Much of Bhopal

21. As a result… Gaseous methyl isocyanate entered the environment which had very stable atmospheric conditions The plume formed was heavier than air and dispersed little as it flowed towards population centers Over 200,000 humans were exposed to methyl isocyanate. Over 10,000 deaths occurred

23. TWO MAJOR EXPLANATIONS WATER ACCIDENTLY ENTERED TANK THROUGH A WATER FLUSHING OPERATION SABOTAGE

24. The Water Washing Theory

25. Overview of the Entire theProcess Vent and Relief Vent Lines

26. Sabotage Theory

27. Pipe Run 20 years ago

28. Pipe Run 4 Dec 2004

29. International Conference on the 20th Anniversary of the Bhopal Gas Tragedy On December 1 to 3, 2004, Prof. J. Gupta of the Indian Institute of Technology – Kanpur organized this conference in Kanpur, India Afterwards, we made an overnight trip by rail to the Bhopal site

30. Presentation by Chief of Police Swaraj Puri Described how he was exposed to MIC vapors Risked his life seeking answers in the dark night to manage the chaos of evacuation. Obtained medical help for the victims, and eventually oversaw the removal and disposal of bodies.

31. Poor communications Less than 10,000 telephones for 900,000 residents at the time. Hampered the discovery of what was affecting the multitudes

32. Presentation from a Plant Operator Workers prided themselves working at the plant. However, change was underway, driven by UC India decision to close its Bhopal operations. Pressure to eliminate costs resulted in personnel layoffs, and decisions mentioned above compromised what could have been a safely run plant.

33. Additionally, Other speakers discussed the long-term health effects, and epidemiology studies and monitoring of the long term health impacts of the disaster have unexpectedly ceased. Finally, many papers related to process safety and how this accident influenced process safety practice across the world were presented.

34. Conditions we found at the plant site

35. The plant operator

36. Tank 610

37. Top of Tank 611

38. Filter Area up Close

39. Valve Connecting to Vent Header

40. End of pipe rack where jumper pipe was located

41. The Scrubber

42. The Flare Tower

43. The Control Room

44. Sign Insidethe Control Room

45. Close up of the sign details

46. Other environmental concernspresence of mercury droplets

47. A corroded tank whose contents are unknown

48. Observations The Bhopal disaster began long before the actual event, and its effects continue today, twenty-one years later. It is clear today that the initiating event is basically irrelevant.

49. 3 Strikes and you are… If even one of the basic protections functioned …e.g. The refrigeration system Or the scrubber, Or the flare, Many, many lives could have been saved.

50. Importance of Communications If communications between the plant and corporate management had been stronger, and if local management had better information and supported There may not have been flawed decisions about fundamental safety principles.

51. The Root Cause Extends Beyond Local Management Decisions Optimistic market-size expectations led to an oversized plant by a factor of three Failure of state and local government to control growth near the plant

52. Consequences extend well beyond December 3, 1984 Thousands of people injured that day continue to suffer And, because Union Carbide was banished so abruptly from the site, the chemicals remaining on site were never properly removed This has lead to additional significant environmental and health impacts

53. Serious accidents are not common It is easy to fall into the mindset that they cannot happen. This is a common human failing, and it explains many risky behaviors from driving too fast on the highway to failure to maintain critical safety systems in a chemical plant.

54. Bhopal clearly disproves this In no circumstances does “unlikely” mean “impossible,” Some possible consequences are clearly so significant that “unlikely” still leaves one with unacceptable risk that must be addressed more aggressively.

55. A Silver Lining Bhopal has lead to improved process safety practices AIChE’s Safety and Health Division and Center for Chemical Process Safety, and throughout many other organizations around the world. Fundamental principles such as Management of Change, Mechanical Integrity, Hazard Analysis, and Layers of Protection are now in the toolbox of most practicing chemical engineers around the world.

56. So… It would be a stretch to say that an accident like Bhopal could never happen today, but as we work together to build a global culture of process safety, the use of the process safety tools – and the strength of process safety practices – will help prevent future Bhopals.

57. Conclusions Every business decision has safety consequences. A negative safety outcome is a negative business outcome. In order to do the right thing, politics and the local community must be assessed, understood, and protected.

58. Questions???