| Question 1: 1. NCRP 147 uses multiple conservative assumptions. Which assumption below is NOT an included conservative assumption? |
| Reference: | Reference: NCRP 147, pages 5 – 6. The public design goal is set to the annual limit. The design goal for controlled areas was set to 10% of the annual limit to be conservative for workers. |
| Choice A: | Attenuation of the primary beam by the patient is neglected. |
| Choice B: | Assume perpendicular incidence on the barrier. |
| Choice C: | The public design goal is set at 10% of the annual limit for the general public. |
| Choice D: | Scattered radiation was measured with large field sizes. |
| Question 2: What is the recommended method for designing barriers given the situation of a shared control room (exposure from multiple sources)? |
| Reference: | Reference: NCRP 147, section 1.4 and the presentation. |
| Choice A: | Reduce the design goal from each source. |
| Choice B: | Increase the occupancy factor at the location. |
| Choice C: | Double the barrier thickness calculated for each source. |
| Choice D: | Assume conservative assumptions will provide enough shielding. |
| Question 3: According to the information presented in this symposium, for the shielding design of a Hologic DBT room, what is the major concern as compared to NCRP 147 recommendation based on 2D mammography? |
| Reference: | “Scatter radiation intensities around a clinical digital breast tomosynthesis unit and the impact on radiation shielding considerations”, K Yang, X Li, B Liu, Medical physics 43 (3), 1096-1110 |
| Choice A: | Much higher work load |
| Choice B: | Much higher beam quality with Tungsten anode |
| Choice C: | Much higher primary dose level with added tomo views |
| Choice D: | Much higher non-uniformity of scatter distribution |
| Question 4: According to the information presented in this symposium, for the shielding design of a dedicated interventional CT room, what is the major difference for a diagnostic CT room? |
| Reference: | “Procedure-specific CT dose and utilization factors for CT-guided interventional procedures”, K Yang, S Ganguli, MC DeLorenzo, H Zheng, X Li, B Liu, Radiology 289 (1), 150-157 |
| Choice A: | Much higher work load |
| Choice B: | Much higher occupancy factor |
| Choice C: | Much higher CTDIvol per exam |
| Choice D: | Much higher DLP per exam |
| Question 5: Automatic tools used for shielding design, such as XRayBarr and RadShield, have the following advantage(s): |
| Reference: | Downloadable software XRAYBARR and RadShield, RadShield: semi-automated shielding design using a floor plan driven graphical user interface |
| Choice A: | Employs iterative method to solve for barrier thickness |
| Choice B: | Report generation |
| Choice C: | Ability to save and load prior shielding design inputs |
| Choice D: | All of the above |
| Question 6: Automatic tools for shielding design are considered for investigative use only and their results should be double checked by the qualified medical physicist (QMP) |
| Reference: | Downloadable software XRAYBARR and RadShield, found in disclaimers and about sections |
| Choice A: | True |
| Choice B: | False |
| Question 7: According to NCRP 184, the total number of CT exams in the United States has increased by what factor between 1996 and 2015? |
| Reference: | NCRP 184, Figure 5.1, Page 61. In 1996, there were 22.6 Million CT exams; by 2015 there were 78.7 Million. |
| Choice A: | 1.5x |
| Choice B: | 2x |
| Choice C: | 3x |
| Choice D: | 5x |
| Question 8: Suppose that a source of F-18 (HVL of lead = 5.11 mm) and a source of Tc-99m (HVL of lead = 0.234 mm) both irradiate the same location from opposite sides such that there is no common wall between both sources and the location in question. Further, suppose that each delivers the same dose over the course of a week and that the sum of those two doses exceeds the weekly targeted dose limit for that location. In order to shield this location with the least amount of shielding material, one should |
| Reference: | Madsen MT, Anderson JA, Halama JR, Kleck J, Simpkin DJ, Votaw JR, et al. AAPM Task Group 108: PET and PET/CT shielding requirements. Medical Physics [Internet]. 2006 Jan;33(1):4–15. Available from: http://www.aapm.org/pubs/reports/RPT_108.pdf |
| Choice A: | Use the same number of half-value layers between each source and the location. |
| Choice B: | Use more half-value layers between the F-18 source and the location and fewer half-value layers between the Tc-99m source and the location. |
| Choice C: | Use more half-value layers between the Tc-99m source and the location and fewer half-value layers between the F-18 source and the location. |
| Question 9: How much attenuation does a CT gantry provide for calculations of protection? |
| Reference: | Radiation Shielding for Diagnostic Radi-ology, Second Edition. Editors: D. G. Sutton, C. J. Martin, J. R. Williams, and D. J.Peet. British Institute of Radiology, Lon-don, UK, 2012. |
| Choice A: | 10% |
| Choice B: | 20% |
| Choice C: | 50% |
| Choice D: | 60% |
| Choice E: | 90% |
| Question 10: In a radiography room at what angle will scatter radiation from a patient to room wall be greater? |
| Reference: | Radiation Shielding for Diagnostic Radi-ology, Second Edition. Editors: D. G. Sutton, C. J. Martin, J. R. Williams, and D. J.Peet. British Institute of Radiology, London, UK, 2012. |
| Choice A: | 130 degrees |
| Choice B: | 120 degrees |
| Choice C: | 110 degrees |
| Choice D: | 100 degrees |
| Choice E: | 90 degrees |
