3.2.1. Shielding the cyclotron vault
With regard to concrete and water shielding containing boron, the issue of disposal as an inorganic element should be mentioned.
3.3.2. Release and monitoring of radioactive gases
A reader would expect to see some concrete examples of reductions in environmental emissions.
Stimson DH, Pringle AJ, Maillet D, King AR, Nevin ST, Venkatachalam TK, Reutens DC, Bhalla R. Management of radioactive waste gases from PET radiopharmaceutical synthesis using cost effective capture systems integrated with a cyclotron safety system. J Radiol Prot. 2016 Sep;36(3):504-517. doi: 10.1088/0952-4746/36/3/504. Epub 2016 Jul 7. PMID: 27383139.
Norifumi ABO, Yoichi NOYA, Kei HIGASHIKAWA, Hironobu YASUI, Yuji KUGE, Development of Compact RI Gas Storage Devices for Placing in a Hot-cell, Japanese Journal of Radiation Safety Management, 2017, Volume 16, Issue 2, Pages 85-90, Released on J-STAGE November 09, 2017, Online ISSN 1884-9512, Print ISSN 1347-1503, https://doi.org/10.11269/jjrsm.16.85
3.6. Design of a PET facility
The various by-products found in waste must also be considered.
Ito S, Saze T, Sakane H, Ito S, Ito S, Nishizawa K. Tritium in [18O]water containing [18F]fluoride for [18F]FDG synthesis. Appl Radiat Isot.61(6), 1179-83,2004
3.6.2. Example of PET/CT facility design
Fig. 3.1. Schematic plan of the layout of a PET/CT facility.
It would be better to show the separation of medical staff flow as well.
5.2. Justification of radiological practices
The justification of radiological practices should include references to specific examples, even if only typical examples at section 5.3.
5.3. Justification of PET, PET/CT, and PET/MRI procedures
(238) In terms of justification review, the cumulative radiation doses from multiple radiological procedures are relevant to the evaluation if they are performed in sequence, but if not, ensuring the justification of the procedure is the basis here.
6.1. Dose estimation of patients
In dose assessment for continuous delivery of radionuclides, such as the use of a generator, it is necessary to consider the form of delivery of the radionuclides, including dose assessment for radiation management purposes. In Japan, there have been cases where airborne concentrations of O-15 have been incorrectly assessed by medical institutions, and the regulatory authorities have provided guidance.
Note that a solution to this issue has been proposed in a study commissioned by the regulatory authority.
7.3 Radiation dose to non-radiation workers
Assuming repeated exposure, medical drivers, medical tour guides, and cafeteria and shop workers in medical facilities may also be considered.
Nakamura F, Kanno T, Okada H, Yoshikawa E, Andou I, Futatsubashi M, Shinke T, Ouchi Y, Torizuka T. [Measurement of radiation exposure to a PET institution driver from patients injected with FDG]. Nihon Hoshasen Gijutsu Gakkai Zasshi. 2006 Aug 20;62(8):1105-10. Japanese. doi: 10.6009/jjrt.62.1105. PMID: 16957665.
Consideration should also be given to wastewater treatment plant workers in areas where PET medical facilities are densely located.
NRPB - W63 Radiological Assessments for Small Users
8.3. Staff dose monitoring
Workplace monitoring with incidence discrimination detectors is also useful.
Hiroshi Muraishi et al. Shift-invariant gamma-ray imaging by adding a detector rotation function to a high-sensitivity omnidirectional Compton camera. 2020 Jpn. J. Appl. Phys. 59 090911
Direct-reading air dose rates installed on walls are also beneficial to cleaning workers. Dosimeters that can record dose rate trends are also utilized.