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ORAU Team Document Number: ORAUT-TKBS-0006-6 NIOSH Dose Reconstruction Project Effective Date: 10/05/2006 Revision No.: 01 PC-1 Technical Basis Document for the Hanford Site – Controlled Copy No.: ______ Occupational External Dosimetry Page 1 of 80 Subject Expert: Jack Fix Supersedes: Document Owner Approval: Signature on File Date: 01/09/2004 Edward D. Scalsky, TBD Team Leader Revision No.: 00 Approval: Signature on File Date: 01/09/2004 Judson L. Kenoyer, Task 3 Manager Concurrence: Signature on File Date: 01/09/2004 Richard E. Toohey, Project Director Approval: Signature on File Date: 01/09/2004 James W. Neton, OCAS Health Science Administrator TABLE OF CONTENTS Section Page Record of Issue/Revisions ................................................................................................................... 5 Acronyms and Abbreviations ............................................................................................................... 6 6.1 Introduction ................................................................................................................................. 8 6.1.1 Purpose ............................................................................................................................ 9 6.1.2 Scope ............................................................................................................................... 9 6.2 External Dosimetry ...................................................................................................................... 9 6.3 Basis of Comparison ................................................................................................................. 10 6.4 Dose Reconstruction Parameters ............................................................................................. 10 6.4.1 Hanford Historical Administrative Practices ..................................................................... 11 6.4.2 Hanford Dosimetry Technology ....................................................................................... 13 6.4.2.1 Beta/Photon Dosimeters ........................................................................................ 14 6.4.2.2 Neutron Dosimeters ............................................................................................... 17 6.4.3 Calibration ...................................................................................................................... 18 6.4.3.1 Hanford Beta/Photon Dosimeters ........................................................................... 18 6.4.3.2 Hanford Neutron Dosimeters .................................................................................. 20 6.4.4 Workplace Radiation Fields ............................................................................................ 21 6.4.4.1 Hanford Beta/Photon Dosimeter Response Testing ............................................... 21 6.4.4.2 Hanford Workplace Beta/Photon Dosimeter Response .......................................... 26 6.4.4.3 Uncertainty in Beta/Photon Recorded Dose ........................................................... 26 6.4.4.4 Hanford Neutron Dosimeter Response Testing ...................................................... 30 6.4.4.5 Hanford Workplace Neutron Dosimeter Response ................................................. 33 6.4.4.6 Neutron to Photon Ratio ......................................................................................... 39 6.4.4.7 Neutron Dose Fraction ........................................................................................... 44 Effective Date: 01/09/2004 Revision No. 01 Document No. ORAUT-TKBS-0006-6 Page 2 of 80 6.4.4.8 Uncertainty in Neutron Dose .................................................................................. 46 6.5 Adjustments to Recorded Neutron Dose ................................................................................... 46 6.5.1 Neutron Dose Adjustments ............................................................................................. 46 6.5.2 Neutron Weighting Factor ............................................................................................... 47 6.5.3 Neutron Correction Factor............................................................................................... 48 6.6 Missed Dose ............................................................................................................................. 48 6.6.1 Photon Missed Dose ....................................................................................................... 48 6.6.1.1 Year ....................................................................................................................... 49 6.6.2 Neutron Missed Dose ..................................................................................................... 49 6.6.2.1 Year ....................................................................................................................... 50 6.6.2.2 Facility/Location ..................................................................................................... 50 6.6.2.3 Dosimeter Type ...................................................................................................... 51 6.6.2.4 Energy Range ........................................................................................................ 51 6.7 Uncertainty ................................................................................................................................ 51 6.7.1 Missed Dose ................................................................................................................... 51 6.7.2 Positive Recorded Photon Dose ..................................................................................... 53 6.7.3 Neutron Dose.................................................................................................................. 54 6.7.4 Organ Dose .................................................................................................................... 54 References ........................................................................................................................................ 55 Glossary ............................................................................................................................................ 60 Attachment 6E Occupational External Dose for Monitored Workers .............................................. 70 6E.0 Distribution Parameters ............................................................................................................. 71 6E.1 Years of Exposure .................................................................................................................... 71 6E.2 Rate .......................................................................................................................................... 71 6E.3 Radiation Type .......................................................................................................................... 71 6E.3.1 Beta/Photon .................................................................................................................... 71 6E.3.2 Neutron ........................................................................................................................... 72 6E.4 Distribution Parameters ............................................................................................................. 73 6E.4.1 Type ............................................................................................................................... 73 6E.4.2 Parameter 1 .................................................................................................................... 73 6E.4.2.1 Resolution of Recorded Dose Components ............................................................ 74 6E.4.2.2 Adjustments to Recorded Penetrating Dose ........................................................... 74 6E.4.2.3 Adjustments to Recorded Neutron Dose ................................................................ 75 6E.4.2.4 Unmonitored Photon Dose ..................................................................................... 76 6E.4.2.5 Missed Photon Dose .............................................................................................. 77 6E.4.2.6 Missed Neutron Dose ............................................................................................. 77 6E.4.2.7 Organ Dose ............................................................................................................ 79 6E.4.3 Parameter 2 .................................................................................................................... 80 6E.4.3.1 Hanford Workplace Recorded Dose Uncertainty .................................................... 80 Effective Date: 01/09/2004 Revision No. 01 Document No. ORAUT-TKBS-0006-6 Page 3 of 80 LIST OF TABLES Table Page 6-1 Hanford historical dosimetry events ....................................................................................... 15 6-2 Laboratory sources of uncertainty for beta/photon dosimeter calibration parameters ............................................................................................................................. 19 6-3 Analysis of two-element film dosimeter dose. ......................................................................... 20 6-4 Laboratory sources of uncertainty for neutron dosimeter calibration parameters .................... 21 6-5 IARC testing results