The South Texas Project responds as follows: As you know, the beta correction factor for an ion chamber depends upon the beta energy and the geometry of the chamber. Several years ago, STP decided to use a generic beta correction factor for our ion chambers (RO-20s) using Tl-204 as a reference. (Our average beta energy is quite low.) As a result, we use a beta correction factor of 5 for contact measurements and measurements up to a foot away from the source. On the rare (if ever) occasion we make a beta measurement greater than a foot away from a source, we use a beta correction factor of 3 for these measurements.
Regards, Leonard Earls Consulting Engineer 361-972-7759 _____________________________________________ From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Wednesday, January 04, 2012 09:44 To: [email protected] Subject: Powernet: Beta Correction Factor for Handheld Ion Chamber Instruments Palo Verde requests the following information: What beta source is used to establish beta correction factors for handheld ion chambers (RO-20, RO-2/2A, RSO-50E) at your facility? Is a generic beta correction factor is assigned (such as 4 or 5) or is the specific value established during calibration assigned (such as 3.8)? Thanks Gordon Nelson Radiological Engineering Palo Verde Nuclear Generating Station Phone (623) 393-5200 Cell (623) 238-0542 Pager (877) 466-7534 [email protected]
