The Bhopal gas tragedy was one of the world's worst industrial disasters. On December 2-3 1984, a leak of methyl isocyanate gas and other chemicals from a Union Carbide India pesticide plant in Bhopal, India exposed hundreds of thousands of people. Over 500,000 injuries were reported and thousands died in the aftermath from toxic exposure. Safety procedures were minimal at the plant. The Chernobyl disaster was the worst nuclear power plant accident in history. On April 26 1986, a safety test caused an uncontrolled nuclear chain reaction and subsequent explosions at the Chernobyl nuclear power plant in Ukraine. Large amounts of radioactive materials were released into the atmosphere, contaminating parts of the USSR

1. Man Made Disasters : Case
Studies
M.Starwin

2. Bhopal Gas Tragedy
• The Bhopal disaster, also referred to as the
Bhopal gas tragedy, was a gas leak incident in
India, considered one of the world’s worst
industrial disasters.
• It occurred on the night of 2-3 December 1984 at
the Union Carbide India Limited (UCIL) pesticide
plant in Bhopal, Madhya Pradesh, India.
• A leak of methyl isocyanate gas and other
chemicals from the plant resulted in the exposure
of hundreds of thousands of people.

3. • A government official declaration in 2006 stated
the leak caused 558,125 injuries including 38,478
temporary partial and approximately 3,900
severely and permanently disabling injuries.
• There were mass funerals and mass cremations
as well as disposal of bodies in the Narmada
River. 170,000 people were treated at hospitals
and temporary dispensaries. 2,000 buffalo, goats,
and other animals were collected and buried.

4. • The gas cloud was composed mainly of
materials denser than the surrounding air,
stayed close to the ground and spread
outwards through the surrounding
community.
• The early effects of exposure were coughing,
vomiting, severe eye irritation and a feeling of
suffocation.

5. • Owing to their height, children and other
people of shorter height inhaled higher
concentrations.
• The events in Bhopal revealed that growing
industrialization in developing countries
without concurrent evolution in safety
regulations could have terrible consequences.

6. • Even without enforcement, international standards
could provide norms for measuring performance of
individual companies engaged in hazardous activities
such as the manufacture of pesticides and other
toxic chemicals in India National governments and
international agencies should focus on widely
applicable techniques for corporate responsibility
and accident prevention as much in the developing
world context as in advanced industrial nations
specifically, prevention should include risk reduction
in plant location and design and safety legislation.

7. • Local governments clearly cannot allow
industrial facilities to be placed within urban
areas, regardless of the evolution of land use
over time. Industry and government need to
bring proper financial support to local
communities so they can provide medical and
other necessary services to reduce morbidity,
mortality and material loss in the case of
industrial accidents.

8. • The Bhopal disaster could have changed the
nature of the chemical industry and caused a
reexamination of the necessity to produce such
potentially harmful products in the first place.
• Safety procedures were minimal and neither the
American owners nor the local management
seemed to regard them as necessary. When the
disaster struck there was no disaster plan that
could be set into action.

9. • We need to introduce a system of laws which
will make them liable for higher standards of
safety.
• Multinationals operating in India, must agree
as a condition of doing business that they will
submit to the jurisdiction of the Indian courts
both civil and criminal.

10. • They must agree to be responsible for the acts
of their subsidiaries.
• Prevention is better than cures. Lesson
learned from this manmade disaster is to
understand the nature of disaster before it
occurs and implement better disaster
management system in place.

11. • When series of accidents occurred frequently
in Bhopal plan, if prevented on time properly
by Union Carbide India Limited they could
avoided this nightmare.

12. Chernobyl Disaster
• The Chernobyl disaster was caused by a nuclear
accident that occurred on Saturday 26 April 1986, at
the No. 4 reactor in the Chernobyl Nuclear Power
Plant, near the city of Pripyat in the north of the
Ukrainian SSR.
• It is considered the worst nuclear disaster in history
and was caused by one of only two nuclear energy
accidents rated at seven, the maximum severity, on the
International Nuclear Event Scale, the other being the
2011 Fukushima Daiichi nuclear disaster in Japan.

13. • The accident started during a safety test on an
RBMK-type nuclear reactor, which was
commonly used throughout the Soviet Union.
• The test was a simulation of an electrical
power outage to aid the development of a
safety procedure for maintaining reactor
cooling water circulation until the back-up
electrical generators could provide power.

14. • This gap was about one minute and had been
identified as a potential safety problem that
could cause the nuclear reactor core to
overheat.
• It was hoped to prove that the residual
rotational energy in a turbine generator could
provide enough power to cover the gap.

15. • Three such tests had been conducted since 1982,
but they had failed to provide a solution.
• On this fourth attempt, an unexpected 10-hour
delay meant that an unprepared operating shift
was on duty.
• During the planned decrease of reactor power in
preparation for the electrical test, the power
unexpectedly dropped to a near-zero level.

16. • The operators were able to only partially
restore the specified test power, which put the
reactor in a potentially unstable condition.
• This risk was not made evident in the
operating instructions, so the operators
proceeded with the electrical test.

17. • Upon test completion, the operators triggered
a reactor shutdown, but a combination of
unstable conditions and reactor design flaws
caused an uncontrolled nuclear chain reaction
instead.
• A large amount of energy was suddenly
released, vaporising superheated cooling
water and rupturing the reactor core in a
highly destructive steam explosion.

18. • This was immediately followed by an open-air
reactor core fire that released considerable
airborne radioactive contamination for about
nine days that precipitated onto parts of the
USSR and western Europe, before being finally
contained on 4 May 1986.
• The fire gradually released about the same
amount of contamination as the initial
explosion.

19. • As a result of rising ambient radiation levels
off-site, a 10-kilometre (6.2 mi) radius
exclusion zone was created 36 hours after the
accident.
• About 49,000 people were evacuated from
the area, primarily from Pripyat.

20. • The exclusion zone was later increased to 30
kilometres (19 mi) radius when a further
68,000 people were evacuated from the wider
area.
• The reactor explosion killed two of the reactor
operating staff.

21. • In the emergency response that followed, 134
station staff and firemen were hospitalized
with acute radiation syndrome due to
absorbing high doses of ionizing radiation.
• Of these 134 people, 28 died in the days to
months afterward and approximately 14
suspected radiation-induced cancer deaths
followed within the next 10 years.

22. • Among the wider population, an excess of 15
childhood thyroid cancer deaths were
documented as of 2011.
• The United Nations Scientific Committee on the
Effects of Atomic Radiation (UNSCEAR) has, at
multiple times, reviewed all the published
research on the incident and found that at
present, fewer than 100 documented deaths are
likely to be attributable to increased exposure to
radiation.

23. • Model predictions with the greatest
confidence values of the eventual total death
toll in the decades ahead from Chernobyl
releases vary, from 4,000 fatalities when solely
assessing the three most contaminated former
Soviet states, to about 9,000 to 16,000
fatalities when assessing the total continent of
Europe.

24. • To reduce the spread of radioactive
contamination from the wreckage and protect
it from weathering, the protective Chernobyl
Nuclear Power Plant sarcophagus was built by
December 1986.
• It also provided radiological protection for the
crews of the undamaged reactors at the site,
which continued operating.

25. • Due to the continued deterioration of the
sarcophagus, it was further enclosed in 2017 by
the Chernobyl New Safe Confinement, a larger
enclosure that allows the removal of both the
sarcophagus and the reactor debris, while
containing the radioactive hazard. Nuclear clean-
up is scheduled for completion in 2065.
• The Chernobyl disaster is considered the worst
nuclear power plant accident in history, both in
terms of cost and casualties.

26. • The initial emergency response, together with
later decontamination of the environment,
ultimately involved more than 500,000 personnel
and cost an estimated 18 billion Soviet rubles-
roughly US$68 billion in 2019, adjusted for
inflation.
• The accident resulted in safety upgrades on all
remaining Soviet-designed RBMK reactors, of
which 10 continue to be operational as of 2019.