Chernobyl disaster Chernobyl disaster The Chernobyl disaster, also referred to as the Chernobyl accident, was a catastrophic nuclear accident. It occurred on 25–26 April 1986 in the No. 4 light water graphite moderated reactor at the Chernobyl Nuclear Power Plant near the now-abandoned town of Pripyat, in northern Ukrainian Soviet Socialist Republic, Soviet Union, approximately north of Kiev. The event occurred during a late-night safety test which simulated a station blackout power-failure, in the course of which safety systems were intentionally turned off. A combination of inherent reactor design flaws and the reactor operators arranging the core in a manner contrary to
Chernobyl disaster of about 4,000 among the 5 million persons residing in the contaminated areas. The report projected cancer mortality "increases of less than one per cent" (~0.3%) on a time span of 80 years, cautioning that this estimate was "speculative" since at this time only a few cancer deaths are linked to the Chernobyl disaster. The report says it is impossible to reliably predict the number of fatal cancers arising from the incident as small differences in assumptions can result in large differences in the estimated health costs. The report says it represents the consensus view of the eight UN organizations.