Re: Plutonium spontaneously combusting???

[jatalbq@ix.netcom.com (Joseph A Tompkins )]

The temperature at which spontaeous combustion of Pu metal occurrs is 
governed by impurities (% alloy), % O2 & inerting gas type,  moisture 
content, surface area, surface oxidation state, and temperature of the 
Pu.  Whether or not a particular metal sample can auto heat (via slow 
oxidation ) to the lowest ignition temperature is typically determined 
by the heat transfer characteristics of the container or surface on 
which the material is placed and the total mass of the Pu.

One good reference is "Plutonium Glovebox Alternative Fire Prevention 
Study", Report NO. WSRC-TR-92-599 (12/04/91), which states "There is 
always a risk of spontaneous ignition of finely divided or powder Pu in 
a high moisture content atmosphere.  However, actual ignition of 
massive metal pieces of Pu requires very high temperatures and is very 
difficult."  This report lists about 21 references.

Another source of information is the "Plutonium Handbook (A Guide to 
the Technology)", Gordon and Breach Publishers, 1967, chapter 6, which 
gives and indication of the range of environmental conditions over 
which Pu will ignite.