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Potential Doses to Individuals Screened with Whole-Body Security Screening Systems: OSL Dosimeter Measurements. Craig R. Jones, CHP Fran Szrom, CHP. June 2011. UNCLASSIFIED. Disclaimer.
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Potential Doses to Individuals Screened with Whole-Body Security Screening Systems: OSL Dosimeter Measurements Craig R. Jones, CHP Fran Szrom, CHP June 2011 UNCLASSIFIED
Disclaimer The appearance of a manufacturer’s equipment does not imply endorsement of the equipment by the Army, DOD, or the Federal Government. UNCLASSIFIED
Introduction to Personnel Security Screening Systems • Individual Screened • General-Use: 0.25 μSv (25 μrem) per screening • Limited-Use: 0.01 mSv (1 mrem) per screening • 0.25 mSv (25 mrem) per year • Operator’s/Bystanders Annual Limit • 1 mSv (100 mrem) per year • Inspection zone – operators and bystanders outside inspection zone during screening UNCLASSIFIED 3
Background • Purpose: Evaluate potential dose to the individual being screened • Field measurements • ANSI N43.17-2009 methodology (Reference Effective Dose) • Energy correction, Dose conversion factors • No estimate of eye or skin doses with survey instruments • Dosimeter study requires • Very large number of screenings • Automated method for initiating screenings • Using DDE as a surrogate for Reference Effective Dose UNCLASSIFIED
Test Setup – Repetitive Screening • System 1: • Robotic solution • 93,105 screenings • ~ 2 weeks • System 2: • Software solution • 8,627 screenings • < 1 week UNCLASSIFIED
Test Setup - Phantoms UNCLASSIFIED
System 1: Deep Dose Equivalent • Maximum DDE per screening: • 4,200 μSv/93,105 screenings = 0.045 μSv (4.5 μrem) • Average DDE per screening: • 3,559 μSv/93,105 screenings = 0.038 μSv (3.8 μrem) • Minimum DDE per screening: • 2,560 μSv/93,105 screenings = 0.027 μSv (2.7 μrem) UNCLASSIFIED
System 1: Lens Dose Equivalent • Maximum LDE per screening: • 8,450 μSv/93,105 screenings = 0.091 μSv (9.1 μrem) • Average LDE per screening: • 6,226 μSv/93,105 screenings = 0.067 μSv (6.7 μrem) • Minimum LDE per screening: • 4,710 μSv/93,105 screenings = 0.051 μSv (5.1 μrem) UNCLASSIFIED
System 1: Shallow Dose Equivalent • Maximum SDE per screening: • 15,050 μSv/93,105 screenings = 0.162 μSv (16.2 μrem) • Average SDE per screening: • 10,552 μSv/93,105 screenings = 0.113 μSv (11.3 μrem) • Minimum SDE per screening: • 7,420 μSv/93,105 screenings = 0.080 μSv (8.0 μrem) UNCLASSIFIED
System 2 UNCLASSIFIED 10
System 2: Deep Dose Equivalent • Maximum DDE per screening: • 540 μSv/8,627 screenings = 0.063 μSv (6.3 μrem) • Average DDE per screening: • 416 μSv/8,627 screenings = 0.048 μSv (4.8 μrem) • Minimum DDE per screening: • 250 μSv/8,627 screenings = 0.029 μSv (2.9 μrem) UNCLASSIFIED
System 2: Lens Dose Equivalent • Maximum LDE per screening: • 650 μSv/8,627 screenings = 0.075 μSv (7.5 μrem) • Average LDE per screening: • 516 μSv/8,627 screenings = 0.060 μSv (6.0 μrem) • Minimum LDE per screening: • 280 μSv/8,627 screenings = 0.033 μSv (3.3 μrem) UNCLASSIFIED
System 2: Shallow Dose Equivalent • Maximum SDE per screening: • 780 μSv/8,627 screenings = 0.090 μSv (9.0 μrem) • Average SDE per screening: • 577 μSv/8,627 screenings = 0.067 μSv (6.7 μrem) • Minimum SDE per screening: • 280 μSv/8,627 screenings = 0.033 μSv (3.3 μrem) UNCLASSIFIED
Summary • Both systems evaluated comply with the ANSI/HPS N43.17-2009 dose per screening limit for general-use • DDE is comparable to the Reference Effective Dose (ANSI/HPS N43.17-2009) • The annual number of screenings per individual is limited by the DDE/Reference Effective Dose, not LDE or SDE. UNCLASSIFIED