This is about an incident which occurred in a nuclear power plant at Chernobyl ,Ukraine in April 1986.At that time the engineers at the plant were conducting a test on RBMK reactors which were graphite moderated to decide how long the mechanical inertia of the turbine -generators rotating mass could keep the generator turning and keep producing electric power after the shut down of the steam supply.To conduct the test the unit had been reduced its output up to 700 MW.But due to an unexpected demand the power dispatch controller of ukraine asked the officials of the plant to maintain high power output.First mistake committed by the reactor operators was that they disconnected the emergency cooling system and also the control device was not properly
reprogrammed to maintain the output limits between 700 to 100 MW.
The engineers started the test under unsafe conditions and allowed the reactor to run freely The temperature of the reactor was increased and hence the fission rate increased Due to this the reactor core broke into pieces and with in a second a large explosion occurred.the surrounding people didn’t know about this, they came to know only after a few hours later.Due to this acute radiation many of the workers in the complex died immediately and the toll of death was estimated as 8000 and the agricultural products were contaminated due to contamination by radioactive particles.It was one of the biggest accidents of the century and it was due to the carelessness of the workers and improper training.
