Re: H-3 Signs

[Paul Lavely <lavelyp@uclink4.berkeley.edu>]

Dave,

>Consider the life saving purpose of the sign,

I agree that they serve a very useful purpose; however, that purpose 
(IMHO) should be to serve in locations where it is impractical or 
impossible to use powered signs.

I used to manage the UC Berkeley Fire Marshall and his staff. It was 
his opinion  that most of the H-3 signs on campus were unnecessary 
and the product of "poor planning during construction." Note - these 
are his words and not mine.


>To me $8,000 is a small
>price to pay compared with the loss of life or serious injury that could
>result if signs were not there.


Again, I agree; however, it will not be you or I doing the choosing. 
The disposal choice will be on the shoulders of a hotel maintenance 
manager or the hotel manager. I expect that neither of these will 
know the proper disposal or recycling method nor will they know the 
consequences of improper disposal.


>a hotel with 400 - 600 signs would be if they were
>involved in a fire.  Any H-3 gas released would combine with oxygen (burn)
>and form tritiated water which would vaporize from the heat.  At 20 Ci per
>sign, this could lead to a lot of H-3 contamination.  Consider the
>potential consequences and cost of cleanup for that scenario.

We looked into this scenario. Here, if the fire is hot enough to melt 
the sign and release the H-3 from the tubes, the heat of the fire 
will be expected to disperse most or all of the water vapor with the 
H-3 and little contamination will occur. We are looking to work with 
the local fire departments to do some surveys for H-3 contamination 
after a fire in a building that released H-3 from signs.

Thanks for the response - it allowed me to clarify a few things I 
should have put in the original.

Paul Lavely <lavelyp@uclink4.berkeley.edu>

>

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