H-3 signs

["Kjell A. Johansen" <kajohans@powercom.net>]

Paul Lavely considered a scenario in which the glass tubes of a
tritiated sign melted.
Several years ago we had a fire at a fossil plant that was being
renovated.  Six h-3 powered signs were in the fire with three of them
being severely damaged.  In putting out the fire, the water pressure
blasted  the loose glass tubes out of the open door and on to the
turbine hall roof.  I was able to find all but two tubes.  Six were on
the turbine hall roof, four were on the floor below, and several were
out in a hallway.  None were broken and all glowed in the dark.  The
fire was hot enough to twist metal walkways as well as melting the front
of the signs.  None of the glass tubes showed any signs of damage.
Therefore, I do not think that a scenario in which the tubes melt is
likely.  For the two tubes I could not find, I postulated that fireman
stepped on a tube and broke it being instantly enveloped in a cloud of
H-3.  The doses were low.

Kjell Johansen
Wisconsin Electric
Milwaukee

As, always, my own opinions and not necessarily those of my company.

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