[ RadSafe ] hand held meters

[JOHN.RICH at sargentlundy.com]

radsafers

We're looking for practical experience on using hand held monitors in an 
outdoor setting.

The background gamma dose rates in the area are about 0.02 mR/hr.
The expected change that we want to see is from about 0.02 mR/hr to 0.04 
mR/hr.
So the dose rate goes from about 0.02 mR/hr to 0.04 - 0.06 mR/hr. (two x 
background to 3 x background)

The questions are:
(1) what kind of hand held monitor would be good to see this change (e.g., 
PIC, GM tube, scintillation detector, etc.)?
(2) since this is outdoors, how long should the surveyor wait for the 
readings to stabilize after a random spike?.

I asked a similar question earlier,  and the consensus seemed to be that 
making these measurements with a hand held monitor was problematic. My 
personal experience in this area is very limited, but it seems like the 
spikes could reach about 0.01 mR/hr and lasted several seconds.

thanx in advance  - -jmr

John Rich
312-269-3768