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

Arzamas-16 criticality accident, 1963

compiled by Wm. Robert Johnston
last modified 14 September 2005

Date: 11 March 1963

Location: Arzamas-16, Sarov, Russia, USSR

Type of event: criticality accident


A critical experiment assembly was being assembled without proper checking procedures. The assembly included a plutonium core with a neutron source in the center, all surrounded by a lithium deuteride reflector. While experimenters were assembling it, a criticality excursion occurred producing a flash of light. At that point the experimenters left the room and the assembly table was manually lowered from the control room (the automatic scram system was not operating). Two experimenters received doses of 370 and 550 rem, respectively. Both experienced radiation sickness and recovered (the first lived to 1989, the second was still alive in 1999).

Consequences: 2 injuries.


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