Bhopal Disaster

In 1984 Union Carbide was operating a pesticide plant (UCIL) in Bhopal, Madhya Redesh India. On the night of December 2-3 1984 the Bhopal gas tragedy took place. The industrial disaster is considered the world’s worst in history. 500,000 people were exposed to methyl isocyante (MIC) gas. The highly toxic substance made its way into and around the small towns located near the plant. Estimates vary on the death toll, with the official number of immediate deaths being 2,259. In 2008  the government of Madhya Pradesh had paid compensation to the family members of 3,787 victims killed in the gas release, and to 574,366 injured victims. A government affidavit in 2006 stated that the leak caused 558,125 injuries, including 38,478 temporary partial injuries and approximately 3,900 severely and permanently disabling injuries. Others estimate that 8,000 died within two weeks, and another 8,000 or more have since died from gas related diseases.

The UCIL factory was built in 1969 to produce the pesticide Sevin using methyl isocyanate (MIC) as an intermediate. In the early 1980s, the demand for pesticides had fallen, but production continued regardless, leading to an accumulation of stores of unused MIC at the Bhopal site. The chemical process employed in the Bhopal plant had methylamine reacting with phosgene to form MIC. The underground storage tanks at the plant were 300% larger than other storage tanks in the industry.

Safety regulations specified that no one tank should be filled more than 50% (i.e., 30 tons) with the liquid MIC. In late October 1984, a maintenance failure caused one tank to lose the ability to pump out the liquid MIC. At the time of that failure the tank contained 42 tons of liquid MIC.

There was a history of leaks at the plant. In 1976 , two local trade unions complained of polution within the plant. In 1981, a worker was accidentally splashed with phosgene as he was carrying out a maintenance job for the plant’s pipes. In a panic he removed his mask and inhaled a large amount of toxic phosgene gas, leading to his death 72 hours later. Following these events, journalist Rajkumar Keswani began investigating and published his findings in Bhopal’s local paper Rapat, in which he urged “wake up, people of Bhopal, you are on the edge of a volcano”. In January 1982, a phosgene leak exposed 24 workers, all of whom were admitted to a hospital. None of the workers had been ordered to wear protective equipment. One month later, in February 1982, an MIC leak affected 18 workers. In August 1982, a chemical engineer came into contact with liquid MIC, resulting in burns over 30% of his body. In October 1982 there was another MIC leak. By early December 1984, most of the plant’s MIC related safety systems were malfunctioning and many valves and lines were in poor condition.

During the late evening hours of December 2, 1984, water was believed to have entered the tank during attempts to unclog it. The introduction of water resulted in a runaway exothermic reaction resulting in excessive pressure build-up. A leak was found by 11:45 pm, and reported to the MIC supervisor on duty at the time. The decision was made to address the problem after a 12:15 am tea break, but it was too late. Plant personnel evacuated the plant without warning the neighborhoods surrounding the plant, setting the stage for the world’s worst industrial disaster.



* Which supports and barriers were in play?

* What were the dynamics?

* Who, or what, won the Tug-of-War?

* Discuss the outcome with your friends and family.

* Use Post # 4 as a reference for the dynamics and the relationships between supports and barriers.