What Happened?

It was just after midnight, December 3, 1984 in Bhopal, India. A succession of events occurred in the Union Carbide India Limited facility that led to the release of ~40 metric tons of methyl isocyanate (MIC) gas. The consequences were tragic: according to the Indian government, more than 3800 people died shortly after the release and thousands were injured.

How Did This Happen?

• The basic cause has been agreed upon by most experts who investigated this event: a significant quantity of water entered the MIC storage tank. Water reacted with MIC, temperature and pressure rose and several safety systems could not deal with the event. Eventually, the vessel’s relief device lifted, releasing MIC vapor.
• 20 years later, the exact water source remains controversial. However, it is clear that installed safety systems did NOT prevent a large release of toxic gas.

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