RE: Criticality accident

["Neil, David M" <neildm@ID.DOE.GOV>]

Even with "safe" vessels, people managed to have accidents by inadvertently changing the parameters.  In a couple of cases I recall reading, their efforts were worthy of Wile E. Coyote. (Except it's not funny when it's real)

 

For anyone not familiar with American cartoons, email me and I'll explain.

Dave Neil               neildm@id.doe.gov

-----Original Message-----
From: RuthWeiner@AOL.COM [mailto:RuthWeiner@AOL.COM]
Sent: Monday, March 18, 2002 7:33 AM
To: joseroze@NETVISION.NET.IL; radsafe@list.vanderbilt.edu
Subject: Re: Criticality accident

Actually the group that puts out the report analyzes each accident in detail, and has a training system in place for both workers and managers.   An important principle to add to the list, beyon "what caused the accident". etc. is "what are the consequences of an accident."  When workers understood this, they were far less likely to take short cuts.

I don't think 21 accidents in 60 years qualifies as "many."  One point I didn't make was that (as I recall the talk) about 3/4 of the 21 accidents happened before 1965, and almost all of those in the period 1955 to 1965, when the pressure to produce plutoium was very great, in both the U. S. and the Soviet Union.  One cause, that was eliminted pretty quickly in the U. S., was the size of the standard chemical processing vessels used.  Just using smaller vessels reduced the risk of an accidental criticality considerably.

I might also point out that most of the criticality process accidents were not in the U. S.  Russia had the largest number, the U. S. second, and a few in great Britain, France, Japan, etc (these are just the process accidents).  

Ruth Weiner, Ph. D.
ruthweiner@aol.com