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 Occurred on 26 April 1986
 Worst nuclear power plant disaster in history
 The only level 7 instance on the international
nuclear event scale.
 Resulted in a severe release of radioactivity
into environment
 Plant not properly designed and could run
with very specific instruction.
 Some scientist conducted a highly risky
experiment that lead to the explosion.
 The operator of the plant failed to follow the
instructions.
 Experiment proposed to test a safety
emergency core cooling feature during the shut
down procedure
 This initially caused steam explosion
 Then second explosion from the ignition of
Hydrogen mixed with air,which tore the top of
the reactor .
 Everything inside including molten
uranium,burning graphite and radioactive
ashes emitted into the atmosphere.
 Roughly 180 tons of enriched uranium in the
reactor. If a large blast had happened, half of
Europe would not currently be depicted on any
maps.
 Not a nuclear explosion.
 No chain reaction or explosion like that in an
atomic bomb.
 However,the amount of radioactive material
released was 400 times that caused by US
bombing on Hiroshima.
 Radioactive fallout spread through the Europe.
 Around 1200 tonnes of molten graphite burned
for around 9 days which causes radioactivity
spread .
 Around 5000 tonnes of boron, dolomite, sand,
clay and lead were dropped on to the burning
core by helicopter in an effort to extinguish the
blaze and limit the release of radioactive
particles.
 An interesting point to follow.
Result of a flawed reactor design
. The resulting steam explosion released at least five
percent of the radioactive reactor core.
 Triggered the release of substantial amounts of radiation
into the atmosphere in the form of both particle and gaseous
radioisotopes.
28 people died within four months : total 56 fatalities as
of 2004 due to radiation.
Four hundred times more fallout released than the atomic
bombing of Hiroshima.
2% increase in cancer rates in much of the population
exposed
provoked a radioactive cloud over Russia, Belarus Ukraine
and other neighbouring countries.
 203 people hospitalized immediately.
 135,000 people evacuated from the area.
 300,000-600,000 people were involved in the
cleanup.
 They received doses of radiation.
 contamination was only a minor addition
compared to bombing.
 A seven-fold increase in DNA mutations has
been identified in liquidators' children
conceived after the accident when compared to
their siblings conceived before.

 28,000 km² contaminated by caesium-137 .
 About 250,000 people living in this
area,contaminated by radiation.
 Some children in the contaminated areas
exposed to high radiation doses of up to 50
grays (Gy).
 one gray represents the deposition of one joule
of energy per kilogram of tissue.
 incidence of thyroid cancer among children in
Belarus.
 10 deaths of thyroid cancer attributed to
radiation.
 no increase in leukemia observed.
Cont…
 greater incidence of other cancers in coming
years
 Among some 600,000 workers exposed in the
first year 4000 might be prone to the cancers.
 No cases of birth defects, adverse pregnancy or
decreased fertility found so far.
 people in the area have suffered a paralysing
fatalism due to myths and misperceptions.
 Psycho-social effects among those affected by
the accident.
Cont…
 A large swath of pine forest killed by radiation.
 Livestock removed during evacuation.
 Levels of radiation examined in various natural
foodstocks in Europe.
 fishes affected in Sweden and Finland.
 physical deformities in the plant and animal
populations in affected areas.
 insect, bird and other animal populations
dramatically diminished.
 Barn swallows having more physical
abnormalities .
 the abundance of invertebrates decreased.
 Brightly colored and migratory birds
particularly sensitive to radioactive
contaminants:says Mousseau
 contaminated dirt, water and food might be
responsible.
Cont…
 concern about contamination of the soil with
strontium-90 and caesium-137.
 Caesium binds to the clay minerals.
 contamination migrating into underground
aquifers ,lakes and ponds.
 Contamination of Paripyat river,a major issue.
 Affecting aquatic life.
 Contaminated soil affecting the local food
supply.
 Large no. of people resettled.
 Still facing problems.
 An increased incidence of thyroid cancer
among children.
 political nature of nuclear energy affecting
Scientific studies
 uncontaminated food sources and food
distribution channels, and public health
measures — might affect the future of the
countries.
 Chernobyl lucky to survive a major nuclear
blast.
 Some people believe help from an Unidentified
Flying Object.
 Hundreds of people claim to see a red flying
object hovering some 300 metres over the
reactor.
 UFO emitted two rays of crimson light towards
the fourth unit.
 The level was decreased almost four times.
This probably prevented a nuclear blast.
 Operators should be aware of the safety
requirements.
 Operating the reactor with key security
systems.
 Better communication between the safety
officers and the operators in charge.
 Don’t shut down the Emergency Core Cooling
System (ECCS).[39]
 Use better design of control rods.
 Use a secure container for the reactor
 reactor safety, notably in eastern Europe.
 the safety of all Soviet-designed reactors improved
vastly.
 Modifications made to overcome deficiencies in all
the RBMK reactors still operating
 Control rods of RBMK reactors modified by
adding neutron absorbers.
 Automated inspection equipment has also been
installed.
 Many other international programmes initiated
following Chernobyl
CHERNOBYL NUCLEAR DISASTER CASE STUDY.pptx

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CHERNOBYL NUCLEAR DISASTER CASE STUDY.pptx

  • 1.
  • 2.  Occurred on 26 April 1986  Worst nuclear power plant disaster in history  The only level 7 instance on the international nuclear event scale.  Resulted in a severe release of radioactivity into environment
  • 3.
  • 4.  Plant not properly designed and could run with very specific instruction.  Some scientist conducted a highly risky experiment that lead to the explosion.  The operator of the plant failed to follow the instructions.  Experiment proposed to test a safety emergency core cooling feature during the shut down procedure
  • 5.  This initially caused steam explosion  Then second explosion from the ignition of Hydrogen mixed with air,which tore the top of the reactor .  Everything inside including molten uranium,burning graphite and radioactive ashes emitted into the atmosphere.  Roughly 180 tons of enriched uranium in the reactor. If a large blast had happened, half of Europe would not currently be depicted on any maps.
  • 6.  Not a nuclear explosion.  No chain reaction or explosion like that in an atomic bomb.  However,the amount of radioactive material released was 400 times that caused by US bombing on Hiroshima.  Radioactive fallout spread through the Europe.  Around 1200 tonnes of molten graphite burned for around 9 days which causes radioactivity spread .
  • 7.  Around 5000 tonnes of boron, dolomite, sand, clay and lead were dropped on to the burning core by helicopter in an effort to extinguish the blaze and limit the release of radioactive particles.  An interesting point to follow.
  • 8. Result of a flawed reactor design . The resulting steam explosion released at least five percent of the radioactive reactor core.  Triggered the release of substantial amounts of radiation into the atmosphere in the form of both particle and gaseous radioisotopes. 28 people died within four months : total 56 fatalities as of 2004 due to radiation. Four hundred times more fallout released than the atomic bombing of Hiroshima. 2% increase in cancer rates in much of the population exposed provoked a radioactive cloud over Russia, Belarus Ukraine and other neighbouring countries.
  • 9.  203 people hospitalized immediately.  135,000 people evacuated from the area.  300,000-600,000 people were involved in the cleanup.  They received doses of radiation.  contamination was only a minor addition compared to bombing.  A seven-fold increase in DNA mutations has been identified in liquidators' children conceived after the accident when compared to their siblings conceived before. 
  • 10.  28,000 km² contaminated by caesium-137 .  About 250,000 people living in this area,contaminated by radiation.  Some children in the contaminated areas exposed to high radiation doses of up to 50 grays (Gy).  one gray represents the deposition of one joule of energy per kilogram of tissue.  incidence of thyroid cancer among children in Belarus.  10 deaths of thyroid cancer attributed to radiation.  no increase in leukemia observed. Cont…
  • 11.  greater incidence of other cancers in coming years  Among some 600,000 workers exposed in the first year 4000 might be prone to the cancers.  No cases of birth defects, adverse pregnancy or decreased fertility found so far.  people in the area have suffered a paralysing fatalism due to myths and misperceptions.  Psycho-social effects among those affected by the accident. Cont…
  • 12.  A large swath of pine forest killed by radiation.  Livestock removed during evacuation.  Levels of radiation examined in various natural foodstocks in Europe.  fishes affected in Sweden and Finland.  physical deformities in the plant and animal populations in affected areas.
  • 13.  insect, bird and other animal populations dramatically diminished.  Barn swallows having more physical abnormalities .  the abundance of invertebrates decreased.  Brightly colored and migratory birds particularly sensitive to radioactive contaminants:says Mousseau  contaminated dirt, water and food might be responsible. Cont…
  • 14.  concern about contamination of the soil with strontium-90 and caesium-137.  Caesium binds to the clay minerals.  contamination migrating into underground aquifers ,lakes and ponds.  Contamination of Paripyat river,a major issue.  Affecting aquatic life.  Contaminated soil affecting the local food supply.
  • 15.  Large no. of people resettled.  Still facing problems.  An increased incidence of thyroid cancer among children.  political nature of nuclear energy affecting Scientific studies  uncontaminated food sources and food distribution channels, and public health measures — might affect the future of the countries.
  • 16.
  • 17.
  • 18.  Chernobyl lucky to survive a major nuclear blast.  Some people believe help from an Unidentified Flying Object.  Hundreds of people claim to see a red flying object hovering some 300 metres over the reactor.  UFO emitted two rays of crimson light towards the fourth unit.  The level was decreased almost four times. This probably prevented a nuclear blast.
  • 19.  Operators should be aware of the safety requirements.  Operating the reactor with key security systems.  Better communication between the safety officers and the operators in charge.  Don’t shut down the Emergency Core Cooling System (ECCS).[39]  Use better design of control rods.  Use a secure container for the reactor
  • 20.  reactor safety, notably in eastern Europe.  the safety of all Soviet-designed reactors improved vastly.  Modifications made to overcome deficiencies in all the RBMK reactors still operating  Control rods of RBMK reactors modified by adding neutron absorbers.  Automated inspection equipment has also been installed.  Many other international programmes initiated following Chernobyl