Aftermath of the Chernobyl disaster

Aftermath of the Chernobyl disaster On April 26, 1986, an explosion occurred at the fourth reactor of the Chernobyl Nuclear Power Plant in the Ukrainian SSR, now Ukraine - Number of people killed in the first three months after the disaster: 31 Number of people killed due to the long-term effects of radiation (15 years): 60-80 - Number of people who survived acute radiation syndrome: 134 Number of people involved in clean-up operations: Over 600,000 Ground contamination Five million hectares of farmland were taken out of use Map showing radioactive contamination with cesium-137, a harmful substance with a long half-life that formed in the disaster - Radius of the exclusion zone around the Chernobyl Nuclear Power Plant: 30 kilometers Cherikov Slavgorod Krasnopolye Total area of affected BELARUS Bryansk- regions, thousands of square kilometers RUSSIA Verka Dobrush Gomel . Khoiniki Narovlya UKRAINE 60 46.5 Vystupovichi The Chernobyl Nuclear Power Plant Copripyat Polesskoye "Chernobyl Pershotravnevoye. Belarus Curies per square kilometer (Ci/sq. km.) Russia 1-5 5-15 15-40 >40 50 • Kiev The curie (symbol Ci) is an off-system unit of radioactivity. In addition to the curie, radioactivity can be measured using the becquerel (Bq), which is equal to one decay per second. Therefore: 1 Ci = 3.7x1010 Bq Ukraine Average radiation doses received by different areas of the population Clean-up workers 1 600,000 people Evacuees 1 116,000 people 1986–1989 ~100mSv 1986 33mSv Residents of restricted areas + 270,000 people 1986-2005 >50mSv Residents of other 1986–2005 10-20mSv contaminated areas 1 5,000,000 people The millisievert equals one-thousandth (0.001) of one sievert. The sievert (symbol: Sv) is a unit measuring the biological effect of radiation on the body. One sievert equals one joule per kilogram. The level of natural background radiation averages about 2.4 millisieverts per year RIANOVOSTI 2011 www.rian.ru