Bhopal gas disaster/plant datails/cause of accident/root cause

1. BHOPAL GAS TRAGEDY
-About Plant
-Cause of disaster
Gaurav Kumar Singh Rajput
Roll no- 15

2. INTRODUCTION
 The Bhopal Disaster which is commonly referred to
as Bhopal Gas Tragedy was a gas leak incident in
India, considered one of the world’s worst industrial
catastrophes.
 It occurred on the night of December 2-3,1984 at
the Union Carbide India Limited, a pesticide plant in
Bhopal, Madhya Pradesh, India.
 A leak of methyl isocyanate gas and other
chemicals from the plant resulted in the exposure of
thousands of people.

3. UNION CARBIDE INDIA LIMITED
 UCIL was the Indian subsidiary of Union Carbide
Corporation (UCC), with Indian Government
controlled banks and the Indian public holding a
49.1 percent stake.
 It started in 1969 at the northern state of India.
 Phosgene, Monomethlyamine, Methyl Isocyanate
(MIC) and the pesticide Carbaryl, also known as
Sevin were manufactured here.

5. PLANT PRODUCTION PROCESS
 UCC produced carbaryl using MIC as an
intermediate.
 After the Bhopal plant was built, other
manufacturers including Bayer produced carbaryl
without MIC, though at a greater manufacturing
cost.

6. PLANT PRODUCTION PROCESS
Methylamine (1) reacts with phosgene (2)
producing methyl isocyanate (3)
which reacts with 1-naphthol (4) to yield
carbaryl (5)

7. CAUSE:-
 According to one theory:
Water leaked into tank from valves while workers
were cleaning the clogged pipe which is 400 feet
above it.
 According to another theory:
Water was directly introduced into tank intentionally
by a worker via a missing pressure gauge .
It resulted in exothermic reaction and finally to a
explosion.

8. OTHER CAUSE:-
 Plant management deficiencies like :
 Lack of skilled operators,
 Reduction of safety management.
 Insufficient maintenance and
 Inadequate emergency action plans.
 Use of a more dangerous pesticide manufacturing
method for decreasing generation cost.
 Plant location close to a densely populated area.

9. CONTRIBUTION OF NEGLIGENCE:-
 UCIL didn’t maintained safety rules.
 A pipe leaked? Don't replace it.
 MIC workers needed more training. They could do
with less.
 The MIC tank alarms had not worked for four years.
 The flare tower and the vent gas scrubber had been
out of service for five months before the disaster.
 To reduce energy costs, the refrigeration system
was idle. The MIC was kept at 20 degrees Celsius,
not the 4.5 degrees advised by the manual.

10.  The steam boiler, intended to clean the pipes, was
out of action for unknown reasons.
 Carbon steel valves were used at the factory, even
though they corrode when exposed to acid.
 According to the operators the MIC tank pressure
gauge had been malfunctioning for roughly a week.
 UCC admitted in their own investigation report that
most of the safety systems were not functioning on
the night of December 3, 1984.

11. Thank you…!