Pressure in tank 610 builds up
alarmingly because of an
extremely violent chemical
reaction and MIC vapour escapes
rupturing a sage disc and
popping the safety valve. Tank
619 was not empty
The vent gas scrubber
is supposed to spray caustic
soda on escaping vapours to
neutralise them. The scrubber
was under maintenance.
Vent liner
Poisonous MIC vapour
escaped from the top of
the 33 meter high vent
line.
The refrigeration system
keeps MIC cool but was out of
commission and tank 610 could
not be cooled to slow down the
reaction.
The water curtain
which could have neutralised the MIC
was designed to reach a height of 12
to 15 metres, but the MIC vapour was
gushing out 33 meters above the
ground.
The flare tower
could not be used because a
length of piping was corroded
and had not been replaced
Carbide’s lies
The gas leak just can’t be from my plant. The
plant is shut down. Our technology just can’t go
wrong. We just can’t have such leaks
At no point during that night did Union
Carbide itself try to reach the authorities
with information about the leak or tell
them what to do
is only an
irritant, it is not
fatal
You apply water and you
get relief
the gas is non-poisonous. there is nothing to do
except to ask the patients to put a wet towel over their
eyes
the leak had been plugged
we don’t know of any
fatalities either in our
plant or in other Carbide
plants due to
health effects
lung ailments and acute breathlessness
winter bronchitis
200,000 affected people and about
50,000 seriously affected
sleeping and
digestion problems
babies examined were low in birth weight. Mothers
themselves were generally malnourished, anaemic
and breastmilk was insufficient
more than five per cent
of the community died
gastrointestinal symptoms like nausea,
vomiting and burning in the stomach
anxiety and depression
Many people were suffering
from sleep disturbance, ‘gas
phobia’, and a feeling of
hopelessness
many families were finding it
difficult to cope with this abnormally
stressful situation in their life, they
strongly advised immediate
psychiatric care.
Contributing Factors
storing MIC in large tanks and
filling beyond recommended
levels
poor maintenance after the
plant ceased MIC production at
the end of 1984
failure of several safety due to poor maintenance
safety systems being switched off to
save money- including MIC tank
refrigeration system which could have
mitigated the disaster severity
situation was worsened by the
mushrooming of slums on the vicinity of the
plant
existent catastrophe plans
shortcomings in health care and
socio-economic rehabilitation
use of a more
dangerous pesticide
manufacturing method
large-scale MIC storage
plant location close to a density populated area
undersized safety devices
the dependence on manual operations
lack of skilled operators
reduction of safety
management
insufficient maintenance
inadequate
emergency
action plans
basic information
Gas Leak incident in India
considered the
world's worst
industrial disasters
Occurred in the night of
December, 2-3, 1984
Union Carbide India Limited (UCIL)
pesticide plant in Bhopal, Madhya
Pradesh
Over 500,000 people were exposed to methyl isocyanate
gas and other chemicals
The toxic substance made its way in and
around the shantytowns located the plant
Official immediate
death toll was
2,259
total of 3,787 deaths related to the gas release
DOW Chemical Company purchased UCC in
2001, seventeen years after the disaster
seven ex-employers were convicted in
Bhopal of causing death by negligence