Stress increases pyrophoricity
a,
Stress can be physical or chemical
b.
Uranium lathe chips more susceptible to spontaneous igni-
tion than annealed metals of same dimensions in sheet form
Ruptured fuel elements in a nuclear reactor present a very
real fire hazard
a.
Chalk River incident
b.
Windscale reactor incident
With fissionable materials, fires are limited by criticality
considerations
Methods used to handle pyrophoric materials
a.
Finer the material the smaller the quantities handled
b.
Layers of pyrophoric material are kept thin
ce.
Initial surface treatment (slow exposure of pyrophoric
materials to dry oxygen)
10.
d.
Keeping pyrophoric materials under an inert atmosphere
e.
Fires fought with graphite powders
Serious pyrophoric incidents that have occurred and corrective
measures taken
a.
.b.
ce.
Y-12 area (1956)
Uranium rolling operation (1956)
Sylvania plant (1956)
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