RE:

["Spell, Bill" <bills@deq.state.la.us>]

     Yours is not an easy question for those of us with "few" of any type of 
instrument, but there are those in the country with large inventories of 
instruments with trade names such as you mention.  Perhaps you'll hear from 
some of them.  However, it is easy to speculate that the life expectance 
depends heavily on how frequently the instrument is used, under what 
conditions (e.g., hospital vs. cross-country pipeline), and whether or not 
someone has left it "on" or left batteries in too long without checking them 
(the latter two, along with failure to survive the "3 foot drop test," are 
the biggest destroyers of portable instrumentation, I suspect).  I think 
your biggest concern needs to be the advance of technology.  The instruments 
I started with not only don't work, but most of them are probably useless in 
light of today's knowledge.  I'd suggest you plan on replacement every 5 - 8 
years if performance is criticial in your line of work.  If it's "go, no-go" 
type of work, fresh batteries and frequent calibration will assure the 
instruments are ready when you need them.  These are just some idle thoughts 
on a Sunday night.  I'm sure you'll get better answers from others.  Good 
luck!

Bill Spell
(bills@deq.state.la.us)

 ----------
From: radsafe
To: Multiple recipients of list
Date: Friday, June 07, 1996 6:53PM

I am attempting to get an estimate of the life expectancy of portable
radiation detection equipment in order to assist several organizations in
long term budget planning. Primarily, we are dealing with Eberline,
Victoreen, Ludlum, Bicron and Technical Associates equipment, including ion
chambers, scintillation counters, Geiger-Mueller counters, pocket ion
chambers, digital dosimeters based on GMs, and a few gas flow proportional
counters. We have so few of any given model, that we really aren't in a
position to use our own statistics.

If you have any information which might help, I would be happy to receive
it. Please direct any responses to redwards@gonzo.wolfe.net. I would be glad
to send the results to interested parties or, if there is a great deal of
interest, post the results to radsafe.

Thank you.

Richard W. Edwards