On the night of April 26, 1986 a large-scale technological catastrophe in history of the manind humanity happened in Ukraine - powerful explosion thundered at the fourth unit that ultimately destroyed the reactor. Radioactive substances emitted in the air in the result of the accident were 30 times more than the ones following a nuclear attack on Hiroshima during World War II. At least 8 million people, primarily liquidators of the disaster suferred radiation exposure the total number of whom made almost 600 thousands. Around Chernobyl 30-kilometer exclusion zone was established - more than 100 thousand people of Ukraine were forced to leave their homes.