Re: I-125 thyroid detector

["Gary H. Kramer" <gkramer@hpb.hwc.ca>]

Greetings

The Human Monitoring Laboratory routinely conducts thyroid measurements 
for I-131 and I-125.  Our detectors have no additional shielding other 
than being in the counting room, which is a lead lined steel chamber.

However, many facilities in Canada do use conical collimaters that are 
lead of about 2 cm thickness.

We have several procedures in place for calibration and can make these 
available to you if you wish.  The HML also supplies phantoms to Canadian 
(and some US labs) for calibration/intercomparison purposes.

Yor MDA will depend on your background.  Typically we have an MDA of 40 
Bq for I-131 and 4 Bq for I-125.  Counting time is 5 minutes.

Regards

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| H     H   M       M   L	|  Gary H. Kramer			      |
| H     H   MM     MM   L	|  Head, Human Monitoring Laboratory	      |
| H     H   M M   M M   L	|  The Canadian National Calibration Reference|
| H     H   M  M M  M   L	|  Centre for In-Vivo Monitoring	      |
| HHHHHHH   M   M   M   L	|  775 Brookfield Road, Ottawa, Ontario	      |
| H     H   M       M   L	|  CANADA K1A 1C1			      |
| H     H   M       M   L	|  Tel: 613 954 6668;  Fax 613 957 1089	      |
| H     H   M       M   LLLLLLL |  GKRAMER@HPB.HWC.CA			      |
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