STP responses to the questions are inserted below. STP uses Siemens/Thermo Mk2 electronic dosimeters.
Regards, Leonard Earls Consulting Engineer 361-972-7759 ________________________________ From: [email protected] [mailto:[email protected]] On Behalf Of Courtenay, Christopher C Sent: Tuesday, December 14, 2010 13:37 To: [email protected] Subject: Powernet: Electronic Dosimeter Bias Duke Energy would like to know the following: 1. Do you bias your EDs to over-respond in the field? Biased yes. Bias needed due to energy dependence of silicon diode detectors, also used in DMC EDs. 2. What bias do you apply if you do? (5%, 10%, etc) Our EDs are biased +10% with respect to a Cs-137 exposure on phantom. 3. Have you noticed a change in ED response due to changing plant conditions (Co58/Co60 ratio changes due to Zinc injection, etc) or specific jobs (weld overlay, alloy 600, etc)? Issues involving ED/TLD agreement are usually traced to wearing issues, e.g., not wearing next to the TLD in a non-uniform field or wearing the ED "backwards". Point of reference - Duke uses the DMC2000S from Mirion. Chris Courtenay Engineer, Duke Energy 980-875-5005 "To the optimist, the glass is half full. To the pessimist, the glass is half empty. To the engineer, the glass is twice as big as it needs to be."
