Howdy James! South Texas Project Nuclear Operating Company has a procedure that says:
"WEAR individual monitoring devices on the front of the torso located between the breast pocket and the belt line. IF two monitoring devices are worn, THEN WEAR both in close proximity (about a hand's width) of each other." And: "Each additional DLR must be accompanied by an SRD in the same area of the body." I added the parenthetical statement in the most recent procedure modification thinking that would unquestionably settle any confusion about a distance between the SRD and DLR, but I guess good Texan English isn't as common as I would like it to be. Merriam-Webster defines "hand" as: "A unit of measure equal to 4 inches (10.2 centimeters) used especially for the height of horses." We Texans have some difficulty thinking of the "width" of a hand meaning the fingers are spread, and we would feel a bit slighted if we tried to buy something stated as a certain measurement of "hands" finding that someone didn't measure it with a flat, fingers-joined, hand-width. A spread hand is defined as a "span", which Webster says is, "The distance from the end of the thumb to the end of the little finger of a spread hand; also: an English unit of length equal to nine inches (22.9 centimeters)." I don't know of anyone who measures stuff from the heel of hand to the finger-tip, as the variance between people would be outrageous and the position of the wrist would alter it from one occasion to another. We buy our SRDs from Thermo-Fisher Scientific already having a clip attached. In the event we need to use a telemetry device, we remove the manufacturer's clip and attach the telemetry transmitter which also has its own clip. In contaminated environments, we put the SRD in a plastic, zipper-seal bag and pack it in a PCE pocket. On occasion we put the SRD into a Faraday bag for welders, which makes it less "Self-Reading", but minimizes false alarms from RF interference. Very Respectfully, Dane A. Kappler Dosimetry Health Physicist South Texas Project Nuclear Operating Company Wadsworth, TX From: James P Stewart [mailto:[email protected]] Sent: Wednesday, August 16, 2017 8:00 AM To: [email protected] Subject: [powernet] Dosimetry Placement **THIS EMAIL IS FROM AN EXTERNAL SENDER OUTSIDE OF THE STPNOC NETWORK. BE CAUTIOUS ABOUT CLICKING LINKS OR OPENING ATTACHMENTS FROM UNKNOWN SOURCES. DO NOT PROVIDE PERSONAL INFORMATION SUCH AS SS#, USER ID/PASSWORD, ETC.** Fermi procedures require the DLR to be within a hand's width distance from the SRD on the person's upper torso to ensure an accurate dose accumulation of the two radiation dose measuring devices. 1. What are your requirements for DLR/SRD placement? 2. If requirement is a hands width, is it open or closed fingers? 3. What type of clips do you use on SRDs (specifically DMC3000) Please send responses to [email protected]<mailto:[email protected]>
