Thank You - False Positives

[Stuart Torf <torfsm@NU.COM>]

First of all, I want to thank everyone for all the responses on "false 
positives". 

It is forums like RADSAFE that are most useful (Thank You, Melissa). 

It was apparent that I should have provided a lot more information than what 
was in my original e-mail. My apologies. Well here it is. 

We use a Harshaw 8810 TLD card. 

Approximately < 1% of our TLDs come up with a "false positive" 

The beta chip #3 is 3.6 mil thick Li7F with a black mylar window (17 mg/cm2). 

We use a "minimum reportable dose" algorithm which gives us a 90% confidence 
level on our beta responses. In essence, we don't see any
betas unless they are > 200 mrem. 

Our background response (chip #3) for the site in question is calculated 
(linear) with an estimated error of 45%. 

The typical beta to gamma dose ratio is anywhere from 2 to 3. Gamma doses are 
usually > 100 mrem. 

The glow curves are analyzed (and in some cases smoothed out by glow curve 
refit/ analysis software) and appear normal in every respect.
(no anomalous peaks or oddball glow curve shapes were identified). 

Once again, thank you for all of your responses. 

Stu Torf 
Northeast Utilities 
torfsm@nu.com