Database of radiological incidents and related events--Johnston's Archive

Mayak Enterprise criticality accident, 1968

compiled by Wm. Robert Johnston
last modified 14 September 2005

Date: 10 December 1968

Location: Mayak Enterprise, Russia, USSR

Type of event: criticality accident with plutonium solution


Solutions of plutonium were being transferred from a large tank into a stainless steel vessel using a glass bottle. While a worker was pouring a second load from the glass bottle into the vessel, a criticality excursion occurred, producing a flash of light and a pulse of heat. The worker dropped the bottle, which shattered and spilled its remaining contents on the floor, and left the room. A smaller excursion occurred while the room was empty. Two supervisors approached the room, but were halted by high radiation readings; the radiation control supervisor prohibited further approach but was misled into leaving, after which the shift supervisor entered the room and attempted to move or drain the vessel. The largest criticality excursion occurred then, exposing the supervisor to 2,450 rem and covering him with plutonium solution. The supervisor died one month later. The worker received a dose of 700 rem, leading to acute radiation sickness and amputation of both legs and one hand; he was still alive in 1999.

Consequences: 1 fatality (2,450 rem), 1 injury (700 rem).


© 2004, 2005 by Wm. Robert Johnston.
Last modified 14 September 2005.
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