Corporate responsibility for industrial incidents
Corporate responsibility for industrial incidents

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Corporate responsibility for industrial incidents

5.2 The incident and its consequences

It is important to establish what happened on the night of 2–3 December 1984 at the Union Carbide Corporation plant in Bhopal.

Activity 6

Doing some independent research online, find out:

How and why did the the leak of toxic chemicals at the Union Carbide plant at Bhopal occur?

While researching the facts of the Bhopal gas leak, consider both the immediate cause of the leak and any evidence of more systemic operational causes for the failure.

It would be a good idea to make a note of who carried out the different investigations into the incident and what their conclusions were. Consider how successful you were in finding the original reports of the investigations and how easy it was to find unbiased reports of the incident.

These website and report suggestions may be useful for the activity.

  • Union Carbide Bhopal Information Center website.

  • Jackson B. Browning, Retired Vice President, Health, Safety, and Environmental Programs, Union Carbide Corporation, Union Carbide: Disaster at Bhopal (1993).

  • Ashok S. Kalelkar, Investigation of Large-Magnitude Incidents: Bhopal as a Case Study (1988), Arthur D. Little Inc., Cambridge, Massachusetts, USA, presented at the Institution of Chemical Engineers Conference On Preventing Major Chemical Accidents.

  • International Confederation of Free Trade Unions and International Federation of Chemical, Energy, and General Workers Unions (1985) Report of the ICFTU–ICEF Mission to Study the Causes and Effects of the Methyl Isocyanate Gas Leak at the Union Carbide Pesticide plant in Bhopal India.

  • Amnesty International report (2004) Clouds of Injustice: Bhopal Disaster 20 Years On.

  • N.D. Jayaprakash (n.d.) Bhopal Gas Leak Disaster: UCC’s Heinous Crime and Response of the Indian State, part 1 and part 2.

  • R.J. Willey, Northeastern University, Boston, MA, D.C. Hendershot, Chilworth Technology Inc., Plainsboro, and S. Berger, CCPS Director, American Institute of Chemical Engineers, New York (2006) The Accident in Bhopal: Observations 20 Years Later.


You will have found that the universally accepted source of the disaster on the night of 2 December 1984 was a leak of methyl isocyanate (MIC), a toxic gas used in the production of pesticides, from a container at the UCIL plant. The leak occurred as a result of water (the exact quantity is unclear) entering a tank of MIC (tank 610); this caused an exothermic reaction, heating the liquid to over 200 °C. The raised pressure caused the tank to vent the toxic fumes into the atmosphere across the city of Bhopal.

You are likely to have discovered that exactly how the water entered tank 610 is disputed and is unlikely to be determined. You may now wish to compare your research on the different reports of the incident with what the author discovered, as summarised below, and then reflect on how difficult you found it to access the findings of some of the different investigations. This may be due to the fact that the incident occurred before the advent of the internet and before the ability to store digital information existed. Alternatively, it may be that there has been no incentive for the Indian authorities or for the Union Carbide Corporation (UCC) to make certain information easily accessible.

Union Carbide reports

UCC conclusions, 1985: the UCC investigation resulted in the ‘Bhopal Methyl Isocyanate Incident Investigation Team Report’. It is reported to have concluded that it would require a large quantity of water to be added directly to the tank for such a reaction to occur. The report points to the fact that no water had entered the tanks in the five years that the factory had been in production and so it was unlikely that it had entered through a fault in the plant’s piping system.

The UCC website does not have a copy of this report and the author found the information above in secondary source material. Although this report is often quoted in articles and books on Bhopal, both the author and the Open University Library failed to track down a copy of this report on the internet in PDF form. There is a hard copy in the British Library.

Report of Arthur D Little Inc., Investigation of Large-Magnitude Incidents, 1988: a firm of consultant chemical engineers commissioned by UCC concluded that the most likely cause was direct entry of the water into the tank through a hose. They disputed the accuracy of the evidence provided by the workers on the site, which indicated that the water entered tank 610 because of the failure of a worker to insert a slip bind (a metal disc inserted between two pipelines to prevent the flow of water into a pipeline) when washing out the pipes.

Report of Jackson Browning, Union Carbide: Disaster at Bhopal, 1993: the Vice President of Union Carbide Corporation Health and Safety Programmes at the time of the Bhopal gas leak went further in his report, stating: ‘Although it was not known at the time, the gas was formed when a disgruntled plant employee, apparently bent on spoiling a batch of methyl isocyanate, added water to a storage tank.’ This view of events is maintained by UCC on its website.

Official Indian investigations

Report of the Vararajan Committee 1985: the Council of Scientific and Industrial Research (CSIR) prepared a Report on Scientific Studies on the Release Factors related to Bhopal Toxic Gas Leakage. It was co-authored by 16 scientists and presented to the Indian Parliament in December 1985. This report supported the view that the water had entered the tank through leaking valves. It states:

In retrospect, it appears the factors that led to the toxic gas leakage and its heavy toll existed in the properties of the very high reactivity, volatility and inhalation toxicity of MIC. The needless storage of large quantities of the material in very large size containers for inordinately long periods as well as insufficient caution in design, choice of materials of construction and in provision of measuring and alarm instruments, together with inadequate controls on systems of storage and on quality of stored materials as well as lack of necessary facilities for quick effective disposal of material exhibiting instability, led to the accident. (Para 5.12)

This report is also difficult to find, and the author relied on an excerpt provided in a book on the disaster entitled The Black Box of Bhopal by Themistocles D’Silva.

The Indian Central Bureau of Investigation (CBI) conducted an investigation of the incident but never published its report. This is significant as the CBI had sealed and controlled the Bhopal plant after the incident and had exclusive access to the records of the unit so it may have obtained evidence not available to the authors of the other reports.

The state of Madhya Pradesh initiated the Singh Commission in December 1984. A year later, just as Justice Singh had overcome various administrative hurdles and was ready to hear evidence, the state government disbanded the commission for having exceeded its time limit and refused applications for an extension of the time limit. Reports in the Indian press at that time indicate that the Indian government was concerned that such a report would compromise the ongoing litigation and claims of the victims (e.g. ‘Madhya Pradesh government commission on gas tragedy wound up’, The Hindu, 18 December 1985, p. 7; T. Singh, ‘Ending an enquiry’, India Today, 15 January 1986).

Other reports

Representatives of the Delhi Science Forum, an Indian not-for-profit public interest organisation, visited the site just after the leak in December 1984 and interviewed the victims, the doctors who treated the victims, and the engineers and operators at the plant. The resultant report states that the water entered tank 610 when a vent line was being washed. It identified that there were some safety and maintenance failings in the plant which meant that the various safeguards were not operating. For instance, the chilling unit that would have cooled the tank had been switched off as an economy measure, and the pipes, vent and feed lines were in poor condition and needed replacing. The report questions why the samples taken from the tank had not detected the presence of water and points to the lack of reliable monitoring devices operating on tank 610. The report notes that when it became clear that the reaction in tank 610 was out of control and a leak of gas unavoidable, no effort was made to initiate steps to alert the population near the plant to the danger.

The International Confederation of Free Trade Unions, International Federation of Chemical, Energy, and General Workers’ Unions (ICFTU–ICEF) Mission sent a fact-finding mission to Bhopal in 1985 and spoke with the workers at the Bhopal plant. Their report concludes that the leak occurred due to a combination of factors – including issues with the design of the plant, the operating procedures, lack of maintenance, faulty equipment, cuts in staffing levels and lack of skilled supervision.


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