Industrial Disasters : A case study of Bhopal Gas Leak Disaster

One of the most disastrous events since the history of chemical industry occurred in Bhopal, the capital city of Madhya Pradesh, on the night of December 02, 1984, in the factory of Union Carbide of India Ltd. (UC1L) due to leakage of Methyl Iso Cynate (MIC) gas. UCIL, a subsidiary of the multi national company Union Carbide Corporation (USA) was in the business of manufacturing agricultural pesticides among other things. MIC was required in these manufacturing activities and was therefore, manufactured and stored at the UCIL plant in Bhopal.

Characteristics of MIC

MIC has very special characteristics which make the chemical very hazardous. Some of the properties of the MIC are:

1. It is extremely volatile and vaporises very easily
2. It can boil at a temperature of 38degrees C, so it is very important to be kept cool.
3. It is chemically very active and reacts violently with water.
4. It is highly toxic, it is about 100 times lethal than cyanide gas.
5. It is heavier than atmospheric air, it stays near the ground after release.

The Disaster

During the night of December 2-3, 1984, about 45 tonnes of MIC (Methyl ISo Cynate) gas leaked from the UCIL (Union Carbide of India Ltd.) plant at Bhopal. MIC was stored in the underground tanks, which became contaminated with water. The contamination produced chemical reaction, followed by a rise in gas pressure and a subsequent leak. The chronology of the events leading to one of the most disastrous events in the history of chemical industry is as follows:

Chronology of the Event

1. December 2, 1984, was a routine day at the UCIL factory in Bhopal

2  MIC was stored in an underground tank. The pipeline washing started at 9:30 p.m. as a routine maintenance operation

3. Between 10:30 – 11:00 p.m.: workers engaged in pipeline washing became aware of a leak. Little attention was however paid considering it a normal leak. A casual attempt was made to trace the source of leakage, but of no use. The leak continued.

4. Around 12:15 – 12:30 a.m.: The pressure in the MIC tank about upto 55 pounds per square inch (which was the maximum the gauge could read). The temperature had also shot up to 200 degree C and was increasing. An operator saw that the concrete above the tank was cracking. About 12:30 a.m., the relief valve of the tank gave away and large quantities of MIC gas leaked into the atmosphere.

6. The workers at the factory realized the risk of a massive disaster. They tried to activate the safety systems available at the factory at about 12:30 a.m. The three safety systems available within the factory and their condition at that time were as under:

7. Turning on the flare tower to burn off toxic gas. This system was not in working condition as a piece of pipeline leading to the tower had been removed for maintenance.

8. Using the vent gas scrubber, which was considered the main line of defence. It was also not in an operational condition.

9. Transferring the MIC from the tank into a nearby spare tank. The gauge of the spare tank indicated that the tank already contained something. This gauge indicator was found defective, later on.

10. After failure in all the three safety systems, the workers attempted to douse the leaking gas with water spray. The water spray reached a height of 100 ft. from the ground, while the leak was at 120, ft. above the ground. At 1.00 a.m., realising that nothing could be done to stop the leak, the workers at the plant fled.

11 At about 1.00 a.m. thousands of people living around the plant were awakened by the suffocating, burning effects of the gas. As on three sides, the UCIL plant was-surrounded by slums and other poor settlements, the people living in these colonies were the worst sufferers.

12. There was no warning or guidance to the general public around this time. There were two types of alarms in the factory, one mild siren for workers and one loud public siren. The public siren was started only at about 2:30 a.m.

13. About 2.00 a.m., a large number of people were rushing out of the town through the highways leaving Bhopal. The mad rush on the main roads of the city resulted in stampedes. About two lakh people had fled the city by 3:30 a.m.. The gas clouds dissipated around 3:30 a.m..

14. By 4:00 a.m. hospitals were crowded with suffering people.

In the wake of the tragic disaster, a large number of people lost their lives and received injuries, many to their lungs and eyes. According to the Government reports, 1754 persons had died and 200,000 were injured.

Removal of dead bodies of livestock

The real problem was the removal of dead bodies of livestock, which was still littered on the streets and houses of the affected areas. About 20 dumpers and six cranes were pressed into service to remove 790 buffaloes, 270 cows, 483 goats, 90 dogs and 23 horses. During the burying operation of dead bodies, adequate Technological Di care was taken to check the spread of epidemic.

Emergency Response and Relief Operations

The preparation for coping with a major accident of unprecedented dimensions affecting the surrounding communities like this one was minimal. After the event the immediate response was chaotic and inadequate. Information regarding the gas- release was late and incomplete. The police and medical services were unaware initially that there had been a release of MIC gas. No one knew about the adverse effects of the gas release and the treatment methods of the affected persons.

For the relief purposes of the affected persons a relief commission was created directly under the Chief Minister. Two additional collectors were made incharge of relief and rehabilitation respectively. The main duties of the additional collectors included the proper field work coordination and to ensure the implementation of administrative directives. Various gas affected localities were divided into seven administrative zones. Each zone was under the administrative control of a deputy collector.

The next of kin of the dead persons were paid immediate ex-gratia compensation of Rs. 10,000. The poor families in the gas affected wards were paid an ex-gratia of Rs. 1500. Wheat and rice were distributed free in the affected localities; The local administration faced problems in the absence of reliable socio-economic surveys which made the identification of poor families very difficult. The gas relief commission and the state department of industry launched schemes to provide alternative employment for the affected people.