RE: Truck-scale scrap detection systems -Reply

[Jim Hardeman <Jim_Hardeman@mail.dnr.state.ga.us>]

Our experience from responding to literally hundreds of
contaminated scrap metal incidents is that the large plastic
scintillators ARE VERY, VERY sensitive ... to the point of
SOMETIMES triggering alarms for trivial sources such as a
layer of refractory brick (containing thorium) at the bottom of a
full gondola car loaded with scrap. They also have a pretty
good record of detecting NORM-contaminated scrap (typically
several thousand dpm) buried under 2-3 feet of scrap steel. 

Jim Hardeman, Manager
Environmental Radiation Program
Environmental Protection Division
Georgia Department of Natural Resources
4244 International Parkway, Suite 114
Atlanta, GA 30354
(404) 362-2675  fax: (404) 362-2653
Jim_Hardeman@mail.dnr.state.ga.us

>>> Stephane Jeanfrancois 08/29/96 12:24 >>>

I know some companies such as Exploranium, Radcom, or
Bicron that are in  that type of business. I don't have the
litterature on hand right now but  I'm searching for it and fax
the info to you . I do know that the first two  companies uses
gigantic plastic scintillator (PVT) that are suppose to  detect
a 1 mR/h source inside a truck. Yes, that is a publicity
statement,  sometime, there are more sensitive, sometime
less, it depends, of course, on  the type of source and the
sheilding provided by the scrap inside the truck  and the truck
itself.