Tokaimura Criticality Accident and Hisashi Ouchi's Death

On September 30, 1999, a criticality accident occurred at the Japan — Tōkai, Ibaraki uranium processing facility in Japan. Senior technician Tokaimura nuclear accidents, along with colleague Tokaimura nuclear accidents and supervisor Tokaimura nuclear accidents, negligently poured seven times the safe amount of uranium into a processing tank. This triggered an uncontrolled nuclear chain reaction, exposing Tokaimura nuclear accidents to the highest radiation dose ever recorded in human history (17,000 mSv). Tokaimura nuclear accidents suffered horrific internal burns, his skin peeled away, and his organs deteriorated. Despite his pleas to die, doctors at the University of Tokyo hospital kept him alive for 83 agonizing days, subjecting him to experimental treatments. He eventually succumbed to multiple organ failure on December 21, 1999. Tokaimura nuclear accidents also died four months later from multiple organ failure. An investigation by the government of Japan concluded the accident was due to a lack of regulatory oversight, poor safety culture, and inadequate worker training. Six officials from Japan — Tōkai, Ibaraki were later charged with professional negligence and received suspended prison terms.