m to turn the turbines of the generator. The operator forced the reactor up to 7% power by removing all but 6 of the control rods. This was a violation of procedure and the reactor was never built to operate at such low power. This type of reactor is very unstable when filled with water. The operator was not successful in getting the flow of water corrected and the reactor was getting increasingly unstable. The operator disabled emergency shutdown procedures because a shutdown would abort the test. By 01:22 AM, when the operators thought they had stable conditions, they decided to start the test. The operator blocked automatic shutdown because of a fear that a shutdown would abort the test and they would have to repeat it. The test began and the remaining turbine was shut down. Power in the reactor began to gradually rise because of the reduction in water flow caused by the turbine shutdown, which lead to an increase in boiling. The operator initiated manual shut down, which lead to a quick power increase due to the control rod design. The reactor reached 120 times its full power. All the radioactive fuel disintegrated, and pressure from all excess steam broke every one of the pressure tubes and blew the entire top shield of thereactor. All of these factors including serious violations of safety operations, dangerous design flaws, and imperfect control systems is what led to the virtually instantaneouscatastrophic increase of thermal power which led to core meltdown. The steam explosion also destroyed part of the building. Radioactive material was then thrown out into the atmosphere for over 10 days. Multiple fires were formed both inside and out of the reactor. By five o'clock the firemen had smothered the flames.In later days, about 5000 tons of materials were thrown into the reactor well from helicopters of the air force to extinguish burning graphite and suppress radiation release. The flow of different substances cont...
