Few accidents happen overnight. Most industrial calamities happen over time. Unfortunately, it’s the tragedy only that makes us take them seriously, but for how long? Bhopal gas tragedy is one of the many accidents which, nearly forty years later, still continues to haunt us. And it did not happen overnight. There were certain key problems at the plant which had begun much prior to the actual accident.
The Bhopal gas tragedy reminds us of how little value does the life of a common citizen hold in a developing nation, and how the large corporate entities get away with their irresponsible conduct without much hassle.
A sneak peak into what happened during the Bhopal Gas Tragedy
It all began, or rather ended on the night of 2nd December 1984. In what began as a routine shift for the workers, everything was not normal behind the scenes.
With six safety systems installed at the plant to keep it safe from accidents, there was very little for the plant workers or the people living nearby to worry about. But later on, as the investigation into the causes of accident progressed, it was revealed that none of the six safety systems was operational on the fateful night. And as a result, thousands were killed overnight after inhaling the toxic Methyl Isocyanate (MIC), turning the city into a graveyard.
To understand what happened at the plant that night, we need to go step by step.
But before jumping at the background, causes and aftermath, let’s first understand what exactly had happened during the incident.
A highly toxic gas, meant to stay isolated in the storage area of the plant, is now out in the air. It’s Methyl Isocyanate commonly referred to as MIC. A gas toxic enough to cause instant death if inhaled in large quantities; a gas that even the government authorities, healthcare department and the factory workers did not know the remedy of, if it leaks into the air.
The plant workers, on the fateful night, had just initiated a routine cleaning task. The unit being cleaned was the chemical processing unit, right next to the storage tanks, but ideally not connected to it, since the MIC was supposed to be in isolation. The pipes of the chemical processing unit were clogged, and they were being cleaned using water. This water somehow reached one of the storage tanks, resulting into a chemical reaction between the water and the MIC gas. An exothermic reaction; where an enormously high amount of heat is released, increasing the temperature of the system.
But since the chemical processing unit and the storage tanks were not interconnected, how come the water from the former system made its way to the latter?
Let’s now go back to the original part; how it all happened. So, embrace yourselves. This is going to be a long ride.
A brief history of UCIL and how it came to be:
A chemical factory, founded in 1934, Union Carbide India Limited (UCIL) was into the production of welding equipment, batteries, industrial chemicals, pesticides and plastics. Post Independence 1947, the Indian government had restricted the foreign investments in the Indian market to promote self-sufficiency. And Union Carbide and Carbon Company (UCC), one of the largest chemical and polymer factories in the United States, was one of the few companies which were allowed to function in India. It held a whooping 50.9% shares in the UCIL.
Setup in 1969, UCIL continued to import the toxic MIC gas for the production of pesticides up until 1979, when the then government of India accorded them the permission to begin its production in-house.
Safety Systems at the Plant on the night of 2nd December 1984
The UCIL plant at Bhopal was equipped with some safety systems to prevent the gas leaks, and also mitigate the effects of the leak, if in case something goes wrong. Unfortunately, none of the safety systems was working when the tragic incident happened.
Some of the key systems were:
1. Refrigeration Unit inside the storage tanks:
MIC being a highly volatile and flammable gas required something to keep its temperature under control at all times. The ideal temperature that was desired was anywhere between 0 and 15 degrees Celsius. To do exactly that, a nitrogen gas padding was installed inside the tanks to keep the gas cool.
What’s more shocking is that the refregiration system at the Bhopal plant was shut off by the factory management just a few months before the gas leak. It was believed that the seals of the pump which helped circulate the MIC gas into the system were vulnerable to leaks and after one seal failure, the system was permanently cut off.
2. Vent Gas Scrubber:
Also known as Caustic Scrubber, this special equipment uses caustic soda to turn the toxic acidic gases into harmless salts.
Now, some reports say that the vent gas scrubber was out of service for maintenance at the time of leak while other reports suggest that it was indeed working, and it was the flowmeter which was nonfunctional. But even it is believed that the scrubbers were working, fact of the matter is they could not come to the rescue.
3. Flare Tower:
When all else fails, flare comes to the play. It’s an equipment designed to burn the gasses as leave the system. At the Bhopal gas plant, a 4-feet long pipeline was incorporated into the system, which was at the time of leak, corroded, and out of service for its maintenance.
With the flare system out of order, the toxic MIC had nowhere but the open air to go.
And even if it worked, the system was just not enough to keep the MIC from escaping into the environment. It was just not good enough to stop such vast amount of gas being released into the air every second.
4. Water Curtain System:
A system was installed at the Bhopal gas plant which would spray water at the leaking gasses preventing them from being circulated to a wider area. But the water curtain system at the UCIL was not adequate enough to deliver any results as it was designed to spray water only up to 15 meters but the gas had reached as far as 50 meters into the air.
5. Absence of Slip Blind in the Jumper Lines:
We had discussed in the beginning of this article that the water being used to clean the pipelines of the chemical processing unit had entered the storage tanks. Here’s how it got there.
The storage tanks, which were to be kept isolated from the rest of the factory, were connected to the chemical processing units through jumper lines just a few days prior to the incident. This was done so that the two could be used interchangeably. And on top of it, the slip blinds, used to the prevent the flow of fluids, were not installed at the junction.
As the factory workers let open the water into the chemical processing unit to remove the clogging, it entered the storage tank E610 and kept flowing into it for hours without any hindrance.
Summary
What we understand from the article is that a regular cleaning task at the plant, coupled with the maintenance lapses and cost-cutting measures, caused the water to inside one of the storage tanks, E610, which were all meant to stay isolated. This reaction between the water and the gas released such vast amounts of heat that no fail-safe at the factory, even if they worked to their best, which they were not, could prevent this toxic gas from being released in the environment.
As a result, thousand died instantly, and hundreds of thousands were left injured without any proper healthcare system at place. Nobody that night knew what made the masses sick, and how to go about easing their pain.
And the consequences of the Bhopal gas tragedy can be seen to this day. Those who survived the impact of harmful MIC gas back then now live with its after effects. Some studies have suggest that men born before 1985, living within an area of 100 sq.km of the accident site have a 27-fold higher risk of cancer. It is yet to be seen as to when the city of Bhopal will get finally get rid of the four-decade-old disaster.
