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All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

MO-AB-201-03: The Alphabet Soup of Regulatory Compliance: Being Prepared for Inspections

The role of the Radiation Safety Officer at a medical facility can be complicated. The complexity of the position is based on the breadth of services provided at the institution and the nature of the radioactive materials license. Medical practices are constantly changing and the use of ionizing radiation continues to rise in this area. Some of the newer medical applications involving radiation have unique regulatory and safety issues that must be addressed. Oversight of the uses of radiation start at the local level (radiation safety officer, radiation safety committee) and are heavily impacted by outside agencies (i.e. Nuclear Regulatory Commission, State Radiologic Health, The Joint Commission (TJC), etc). This session will provide both an overview of regulatory oversight and essential compliance practices as well as practical ways to assess and introduce some of the new applications utilizing radioactive materials into your medical facility. Learning Objectives: Regulatory Compliance and Safety with New Radiotherapies: Spheres and Ra-223 (Lance Phillips) Understand the radioactive materials license amendment process to add new radiotherapies (i.e., SIR-Spheres, Therasphere, Xofigo). Understand the AU approval process for microspheres and Xofigo. Examine the training and handling requirements for new procedures. Understand the process involved with protocol development, SOP in order to define roles and responsibilities. The RSO and The RSC: Challenges and Opportunities (Colin Dimock) Understand how to form an effective Committee. Examine what the Committee does for the Program and the RSO. Understand the importance of Committee engagement. Discuss the balance of the complimentary roles of the RSO and the Committee. The Alphabet Soup of Regulatory Compliance: Being Prepared for Inspections (Linda Kroger) Recognize the various regulatory bodies and organizations with oversight or impact in Nuclear Medicine, Radiology and Radiation Oncology. Examine 10CFR35 requirements as they relate to the everyday practice of Nuclear Medicine and Radiation Oncology. Understand the nature of available guidance documents (e.g., NUREG 1556). Examine the commonalities between TJC and CMS preparedness.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2016

SU-F-T-244: Radiotherapy Risk Estimation Based On Expert Group Survey

Purpose: To evaluate the reliability of RPN (Risk Priority Number) decided by expert group and to provide preliminary data for adapting FMEA in Korea. Methods: 1163 Incidents reported in ROSIS for 11 years were used as a real data to be compared with, and were categorized into 146 items. The questionnaire was composed of the 146 items and respondents had to valuate ‘occurrence (O)’, ‘severity (S)’, ‘detectability (D)’ of each item on a scale from 1 to 10 according to the proposed AAPM TG-100 rating scales. 19 medical physicists from 19 different organizations in Korea had participated in the survey. Because the number of ROSIS items was not evenly spread enough to be classified into 10 grades, 1–5 scale was chosen instead of 1–10 and survey result was also fit to 5 grades to compare. Results: The average O,S,D were 1.77, 3.50, 2.13, respectively and the item which had the highest RPN(32) was ‘patient movement during treatment’ in the survey. When comparing items ranked in the top 10 of each survey(O) and ROSIS database, two items were duplicated and ‘Simulation’ and ’Treatment’ were the most frequently ranked RT process in top 10 of survey and ROSIS each. The Chronbach α of each RT process were ranged from 0.74 to 0.99 and p-value was <0.001. When comparing O*D, the average difference was 1.4. Conclusion: This work indicates the deviation between actual risk and expectation. Considering that the respondents were Korean and ROSIS is mainly composed of incidents happened in European countries and some of the top 10 items of ROSIS cannot be applied in radiotherapy procedure in Korea, the deviation could have been came from procedural difference. Moreover, if expert group was consisted of experts from various parts, expectation might have been more accurate. Therefore, further research on radiotherapy risk estimation is needed.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2016

TU-D-201-02: Medical Physics Practices for Plan and Chart Review: Results of AAPM Task Group 275 Survey

Purpose: AAPM Task Group (TG) 275 is charged with developing riskbased guidelines for plan and chart review clinical processes. As part of this work an AAPM-wide survey was conducted to gauge current practices. Methods: The survey consisted of 103 multiple-choice questions covering the following review processes for external beam including protons: 1) Initial Plan Check, 2) On-Treatment and 3) End-of-Treatment Chart Check. The survey was designed and validated by TG members with the goal of providing an efficient and easy response process. The survey, developed and deployed with the support of AAPM headquarters, was released to all AAPM members who have self-reported as working in the radiation oncology field and it was kept open for 7 weeks. Results: There are an estimated 4700 eligible participants. At the time of writing, 962 completed surveys have been collected with an average completion time of 24 minutes. Participants are mainly from community hospitals (40%), academicaffiliated hospitals (31%) and free-standing clinics (18%). Among many other metrics covered on the survey, results so far indicate that manual review is an important component on the plan and chart review process (>90%) and that written procedures and checklists are widely used (>60%). However, the details of what is reviewed or checked are fairly heterogeneous among the sampled medical physics community. Conclusion: The data gathered from the survey gauging current practices will be used by TG 275 to develop benchmarks and recommendations for the type and extent of checks to perform effective physics plan and chart review processes.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2015

Lens of Eye Dosimetry

An analysis of LANL occupational dose measurements was made with respect to lens of eye dose (LOE), in particular, for plutonium workers. Table 1 shows the reported LOE as a ratio of the “deep” (photon only) and “deep+neutron” dose for routine monitored workers at LANL for the past ten years. The data compares the mean and range of these values for plutonium workers* and non-routine plutonium workers. All doses were reported based on measurements with the LANL Model 8823 TLD.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2017

ADESH Onboarding Booklet

This report is an onboarding booklet from the Associate Director of the Environment Safety and Health group at LANL.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

Improved PARE (Pressurized Airborne Release Equipment) for Powder Venting ARF/RF Testing

This project would design, build and test an improved version of the PARE (Pressurized Airborne Release Equipment) system for (powder venting) ARF/RF testing(DOE 1994). This effort would improve the accuracy of risk estimation for the venting of pressurized powders and the venting of gases through pressurized powders. Previously indicated problematic factors (DOE 1994) would be eliminated and the experimental database would be expanded.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2020

Implementing an aerosol dynamic shape factor for cerium oxide powder

The shape factor (X B ) of bulk powder CeO 2 (cerium oxide) particles is estimated to be X B = 1.34 (dimensionless). This is defined in relation to the measured aerated bulk density (0.91 g cm -3 , Hosokawa Micron, Summit NJ, 2018) of the CeO 2 powder. This information is used to determine the RRF (respirable release factor), and other parameters during drop test experiments of nuclear material storage containers at Los Alamos National Laboratory. The calculation is based on an experimental shape factor (X P = 2.66 dimensionless) for CeO 2 particles of the same (chain aggregate) morphology studied by other researchers. In that work, the shape factor was defined in terms of the maximum possible (compacted) density of CeO 2 material (7.13 g cm -3 ).

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2020

A comprehensive final summary of the MCNP calculations performed concerning the UW 137 Cs release event

This document combines and supersedes earlier reports (e.g. LA-UR-19-32358 and LA-UR-20- 22216) that discussed MCNP-calculated conversion factors (count rate per unit activity per unit area) for collimated 2”x2” NaI detectors (Ludlum model 44-10 and Thermo model SPA3) in contact with various surfaces of interest to the University of Washington 137 Cs release event. These surfaces include: Exterior surface of round and rectangular ducts, Exterior surface of outdoor brick work, Exterior surface of cast iron pipes, Exterior surface of an O 2 filter assembly For each surface, the calculated conversion factors allowed inferences on 137 Cs activity on interior surfaces based on exterior contact measurements of the 662 keV photopeak count rate. The MCNP calculations included the effect of attached collimators (i.e. either a Pb/Sb-based Ludlum or a W-based “Rees” model) on detector response. As a consequence, the conversion factors only apply to the appropriate collimated 2”x2” NaI detector operated in pulse height analysis (PHA) mode. Other assumptions affecting the calculations and valid application of the conversion factors will be outlined below.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Evaluation report on the Thermo Scientific TruDose (neutron,gamma) EPD3

This report summarizes an evaluation study on the Thermo Scientific TruDose n/γ EPD3 by LANL’s RP-SVS group. Two EPD3s were received for assessment (SNs 7500100 and 7500108) along with an EPD3 desktop reader. The evaluation included intercomparisons with Thermo’s N2 EPD which is in wide circulation at LANL but is no longer commercially available. A favourable assessment of the TruDose EPD3 would help support it as a viable option to replace the N2 EPD. The data and observations included in this report could also serve as the basis of a Technical Basis Document for the use of the EPD3 at LANL.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2023

RCT: Module 2.07 Respiratory Protection [Slides]

Internal dosimetry controls require the use of engineering controls to prevent the internal deposition of radioactive and non-radiological contaminants. However, when engineering and administrative controls are not available or feasible, respiratory protection may be necessary. The RCT should know and apply the considerations used in determining the respiratory protection equipment that is most appropriate for the job. The inappropriate use of or the use of the wrong respiratory protection equipment may result in undesirable health effects.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2016

Experimental evaluation of neutron dose in radiotherapy patients: Which dose?

Purpose: The evaluation of peripheral dose has become a relevant issue recently, in particular, the contribution of secondary neutrons. However, after the revision of the Recommendations of the International Commission on Radiological Protection, there has been a lack of experimental procedure for its evaluation. Specifically, the problem comes from the replacement of organ dose equivalent by the organ-equivalent dose, being the latter “immeasurable” by definition. Therefore, dose equivalent has to be still used although it needs the calculation of the radiation quality factor Q, which depends on the unrestricted linear energy transfer, for the specific neutron irradiation conditions. On the other hand, equivalent dose is computed through the radiation weighting factor w{sub R}, which can be easily calculated using the continuous function provided by the recommendations. The aim of the paper is to compare the dose equivalent evaluated following the definition, that is, using Q, with the values obtained by replacing the quality factor with w{sub R}. Methods: Dose equivalents were estimated in selected points inside a phantom. Two types of medical environments were chosen for the irradiations: a photon- and a proton-therapy facility. For the estimation of dose equivalent, a poly-allyl-diglicol-carbonate-based neutron dosimeter was used for neutron fluence measurements and, additionally, Monte Carlo simulations were performed to obtain the energy spectrum of the fluence in each point. Results: The main contribution to dose equivalent comes from neutrons with energy higher than 0.1 MeV, even when they represent the smallest contribution in fluence. For this range of energy, the radiation quality factor and the radiation weighting factor are approximately equal. Then, dose equivalents evaluated using both factors are compatible, with differences below 12%. Conclusions: Quality factor can be replaced by the radiation weighting factor in the evaluation of dose equivalent in radiotherapy environments simplifying the practical procedure.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2015

Model-based versus specific dosimetry in diagnostic context: Comparison of three dosimetric approaches

Purpose: The dosimetric assessment of novel radiotracers represents a legal requirement in most countries. While the techniques for the computation of internal absorbed dose in a therapeutic context have made huge progresses in recent years, in a diagnostic scenario the absorbed dose is usually extracted from model-based lookup tables, most often derived from International Commission on Radiological Protection (ICRP) or Medical Internal Radiation Dose (MIRD) Committee models. The level of approximation introduced by these models may impact the resulting dosimetry. The aim of this work is to establish whether a more refined approach to dosimetry can be implemented in nuclear medicine diagnostics, by analyzing a specific case. Methods: The authors calculated absorbed doses to various organs in six healthy volunteers administered with flutemetamol ({sup 18}F) injection. Each patient underwent from 8 to 10 whole body 3D PET/CT scans. This dataset was analyzed using a Monte Carlo (MC) application developed in-house using the toolkit GATE that is capable to take into account patient-specific anatomy and radiotracer distribution at the voxel level. They compared the absorbed doses obtained with GATE to those calculated with two commercially available software: OLINDA/EXM and STRATOS implementing a dose voxel kernel convolution approach. Results: Absorbed doses calculated with GATE were higher than those calculated with OLINDA. The average ratio between GATE absorbed doses and OLINDA’s was 1.38 ± 0.34 σ (from 0.93 to 2.23). The discrepancy was particularly high for the thyroid, with an average GATE/OLINDA ratio of 1.97 ± 0.83 σ for the six patients. Differences between STRATOS and GATE were found to be higher. The average ratio between GATE and STRATOS absorbed doses was 2.51 ± 1.21 σ (from 1.09 to 6.06). Conclusions: This study demonstrates how the choice of the absorbed dose calculation algorithm may introduce a bias when gamma radiations are of importance, as is the case in nuclear medicine diagnostics.

60 APPLIED LIFE SCIENCES↗
NASA NTRS1979

Meteoroid Protection Methods for Spacecraft Radiators Using Heat Pipes

Various aspects of achieving a low mass heat pipe radiator for the nuclear electric propulsion spacecraft were studied. Specific emphasis was placed on a concept applicable to a closed Brayton cycle power sub-system. Three aspects of inter-related problems were examined: (1) the armor for meteoroid protection, (2) emissivity of the radiator surface, and (3) the heat pipe itself. The study revealed several alternatives for the achievement of the stated goal, but a final recommendation for the best design requires further investigation.

Ernst, D. M.↗
DOE OSTI2016

Best Practice on Facility Characterisation from a Material and Waste End- State Perspective - 16041

Radiological characterisation plays a significant role in the process of decommissioning of shut-down nuclear facilities in order to ensure the protection of the environment and radiation safety. At all stages of a decommissioning programme or project, adequate radiological characterisation is of crucial importance, not least from a material and waste perspective. The radiological characterisation is a key element for planning, controlling and optimising decommissioning and dismantling activities. Experience has shown that data and information from the operation of a facility can - supplemented by recently collected and analysed data and information - be of crucial importance for decisions on waste management and for characterisation of radioactive waste. Once the dismantling has been done, some information may be hard, costly or even impossible to obtain later in the waste management process. This was the reason why the Working Party on Decommissioning and Dismantling (WPDD) of the OECD Nuclear Energy Agency (NEA) decided in late 2013 to extend the mandate of the Task Group on Radiological Characterisation and Decommissioning (TGRCD) for a second phase focusing on nuclear facility characterisation from a waste and material end-state perspective whereas the first phase focused on overall strategies of radiological characterisation. This paper gives an overview of the activities and findings within both phases up to now. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Sci-Fri AM: Quality, Safety, and Professional Issues 03: The Increasing Costs of Shielding Diagnostic CT Scanners in Ontario

Purpose: In Ontario, shielding for all X-ray machines, including CT scanners, must be evaluated according to Safety Code 20A (Health Canada, 1983) which is based on NCRP-49 (NCRP, 1976). NCRP-147 (NCRP, 2004) is the international standard for shielding calculations of CT scanners and is also referenced in Safety Code 35 (Health Canada, 2008) which, was published to supersede SC20A. The goal of this work is to demonstrate the cost effectiveness of NCRP-147 for CT scanner shielding. Methods: CT scanner shielding calculations are performed using SC20A and NCRP-147: A room located on the third floor with the nearest building 75m away A room with high occupancy uncontrolled adjacent spaces Two side by side rooms on the main floor Results: 1. SC20A: The exterior windows required 0.1mm of Pb to protect the public who may occupy the building at 75m. 1. NCRP-147: No additional shielding required. 2. SC20A: Two walls adjacent to high occupancy uncontrolled space required an additional 1.58mm Pb. 2. NCRP-147: No additional shielding required. 3. SC20A: The entire floor and ceiling slabs in both rooms required an additional 0.79mm Pb. In addition, 0.79mm Pb was added to the walls from the ceiling to overlap the existing Pb shielding in the walls. 3. NCRP-147: No additional shielding required. Conclusion: The application of NCRP Report No. 147 affords the required protection to staff and the public, in the true spirit of the ALARA principle, taking into account relevant social and economic factors.

60 APPLIED LIFE SCIENCES↗