Deaths due to the Chernobyl disaster 800 roentgens, twice the normal 50% probability of death dose. The following list is of those directly killed by the explosion and initial radioactivity release, or in the support efforts that followed. Deaths due to the Chernobyl disaster The Chernobyl disaster (, "Chornobylʹsʹka katastrofa", "Chernobyl accident") was considered as one of the worst nuclear disasters in history. It occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in the Ukrainian Soviet Socialist Republic, then part of the Soviet Union, now in Ukraine. The scientific consensus on the effects of the disaster has been developed by the United Nations
Chernobyl disaster phase" and would not dissolve for 800–1000 years. Guidelines for levels of radioiodine in drinking water were temporarily raised to 3,700 Bq/L, allowing most water to be reported as safe, and a year after the accident it was announced that even the water of the Chernobyl plant's cooling pond was within acceptable norms. Despite this, two months after the disaster the Kiev water supply was abruptly switched from the Dnieper to the Desna River. Meanwhile, massive silt traps were constructed, along with an enormous 30m-deep underground barrier to prevent groundwater from the destroyed reactor entering the Pripyat River. Bio-accumulation of