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Radiation Protection Dosimetry

Zaid Q Ababneh, Anas M Ababneh, Sultan Alsagabi, Fahad I Almasoud
Gulf countries are often affected by dust storms which have a significant influence on the environment and public health. The present work examines the radioactivity content in the intense dust storm occurred over Gulf countries on 1 April 2015. The results showed that the average value of 137Cs in dust samples (±SD) is 14.4 ± 1.6 Bq/kg, which is almost two orders of magnitude larger than those in soil samples. 7Be was detected with a considerable amount only in dust samples. The activity concentrations of the natural radionuclides (234,238U, 228,230,232Th, 226,228Ra and 40K) in dust samples were found to be approximately two to three times higher than the corresponding values in soil samples, which is attributed to the abundance of the finest particle size in the dust samples...
October 19, 2017: Radiation Protection Dosimetry
Seung Kyu Lee, Sang I Kim, Jungil Lee, Insu Chang, Jang-Lyul Kim, Hyoungtaek Kim, Min Chae Kim, Bong-Hwan Kim
When neutron survey metres are calibrated in neutron fields, the results for room- and air-scattered neutrons vary according to the distance from the source and the size, shape and construction of the neutron calibration room. ISO 8529-2 recommends four approaches for correcting these effects: the shadow-cone method, semi-empirical method, generalised fit method and reduced-fitting method. In this study, neutron scattering effects are evaluated and compared using the shadow-cone and semi-empirical methods for the neutron field of the Korea Atomic Energy Research Institute (KAERI)...
October 19, 2017: Radiation Protection Dosimetry
Paolo Ferrari, Monia Vadrucci, Alessandro Ampollini, Lorenzo Campani, Luigi Picardi, Concetta Ronsivalle, Francesca Mariotti
The TOP-IMPLART, a new proton therapy facility, is under development in Frascati ENEA Laboratories, near Rome. The project is centered on a medium-energy proton accelerator designed as a sequence of modular linear accelerators (the final energy will be 230 MeV). Being not a commercial product, measurements and simulation are fundamental to characterize the system and the radiation field, even during its construction. In this work some preliminary evaluations of the neutron contamination have been tried. The simulations were validated through some measurements obtaining a satisfactory agreement...
October 19, 2017: Radiation Protection Dosimetry
V Stránský, L Thinová
In the year 2010 a continual radon measurement was established at Mladeč Caves in the Czech Republic using a continual radon monitor RADIM3A. In order to model radon time series in the years 2010-15, the Box-Jenkins Methodology, often used in econometrics, was applied. Because of the behavior of radon concentrations (RCs), a seasonal integrated, autoregressive moving averages model with exogenous variables (SARIMAX) has been chosen to model the measured time series. This model uses the time series seasonality, previously acquired values and delayed atmospheric parameters, to forecast RC...
October 13, 2017: Radiation Protection Dosimetry
Jing Chen, Michael W Cooke, Jean-Francois Mercier
Historical results of natural radioactivity in drinking water were reviewed for a total of 21 communities across Canada from 1975 to 2016. Analyses for 226Ra, 210Pb and total uranium were carried out on monthly composite samples of drinking water from selected Canadian municipalities. Generally speaking, levels of 226Ra, 210Pb and total uranium were found to be low compared to national and international standards for drinking water quality. Because levels were low, federal monitoring programs were discontinued in most communities in 1986 except for Regina, Elliot Lake and Port Hope...
October 13, 2017: Radiation Protection Dosimetry
Olivier Van Hoey, Filip Vanhavere, Lise Verbraeken
Personal neutron dosimetry requires workplace specific correction factors from detailed neutron field characterization. A Bonner sphere system (BSS) with a 3He proportional counter and a 3 inch an a 9 inch sphere was developed at SCK·CEN for rapid neutron field characterization. The BSS energy and angular responses were simulated with MCNPX and validated by irradiations with a thermal neutron beam at the Belgian Reactor 1 (BR1) and 252Cf and Am-Be sources at the SCK·CEN Laboratory for Nuclear Calibration (LNK)...
October 13, 2017: Radiation Protection Dosimetry
Patrice Roch, David Celier, Cécile Dessaud, Cécile Etard
The Nuclear Safety and Radiation Protection French Institute (IRSN) presents its latest assessment from up-to-date diagnostic reference levels (DRL) national data in nuclear medicine (NM). NM departments annually send data to IRSN to estimate the representativeness of current DRLs. Complementary analyses of the data have been performed to evaluate the influence of equipment evolution on practice and patient radiation exposure. Based on data from almost 90% of the French NM departments, some DRL update are proposed...
October 13, 2017: Radiation Protection Dosimetry
Weihua Zhang, Ning Ni, Zhiqiang Wang, Yina Liu, Chunjuan Li, Hailong Luo
Tissue-equivalent proportional counter (TEPC) is a very promising dosemeter for radiation protection in mixed radiation fields. In this article, a portable TEPC system including a spherical homemade TEPC detector and the compact low-power integrated circuit prototype was constructed and tested in gamma and neutron radiation fields. The microdosimetric spectra results displayed that the portable TEPC system could deal with four orders of magnitude voltage pulse signals. And the measured dose equivalent values agreed with reference values, which means the portable TEPC system had fulfilled the test and satisfied the requirement for radiation monitor...
October 13, 2017: Radiation Protection Dosimetry
T Liamsuwan, J Channuie, S Wonglee, M Kowatari, S Nishino
This article describes the characterization of an in-house developed multi-cylindrical moderator neutron spectrometer, which consists of a cylindrical 3He proportional counter and cylindrical moderator shells of different sizes. The response matrix of the spectrometer was calculated by Monte Carlo simulations for neutron energies from 1 × 10-8 to 10 MeV and verified with measurements in 0.144 MeV, 1.2 MeV and 241AmBe neutron standard fields. Influence of scattered neutrons was properly eliminated from the measured response using the shadow cone technique...
October 13, 2017: Radiation Protection Dosimetry
Munish Kumar
No abstract text is available yet for this article.
October 13, 2017: Radiation Protection Dosimetry
N P Hawkes, P Kolkowski, N J Roberts, P Salvador-Castiñeira, G C Taylor, D J Thomas
As part of its wide-ranging neutron metrology capabilities, the National Physical Laboratory in the UK has a thermal neutron facility in which accelerator-produced neutrons are moderated within a large assembly or pile of graphite bricks. The neutron field has previously been well characterised in terms of the fluence rate and energy spectrum at various irradiation positions. However, recent changes to the structure (e.g. enlarging the central irradiation cavity) have prompted a renewal and extension of this work...
October 13, 2017: Radiation Protection Dosimetry
Juha Koivisto, Maureen van Eijnatten, Timo Kiljunen, Xie-Qi Shi, Jan Wolff
The objective of the present study was to assess and compare the effective doses in the wrist region resulting from conventional radiography device, multislice computed tomography (MSCT) device and two cone beam computed tomography (CBCT) devices using MOSFET dosemeters and a custom made anthropomorphic RANDO phantom according to the ICRP 103 recommendation. The effective dose for the conventional radiography was 1.0 μSv. The effective doses for the NewTom 5 G CBCT ranged between 0.7 μSv and 1.6 μSv, for the Planmed Verity CBCT 2...
October 13, 2017: Radiation Protection Dosimetry
N Mojzeszek, M Klodowska, W Komenda, L Stolarczyk, R Kopec, P Olko
For commissioning of a proton therapy unit depth dose distributions must be determined and introduced into the Treatment Planning System. In pencil beam scanning (PBS) technique, integral depth dose (IDD) acquisition should be performed with detector large enough to ensure entire beam laterally broadened by scattered and secondary contributions. The purpose of this article is to quantify, using measurements and Monte Carlo transport calculations, the ionization chamber's (IC) geometrical efficiency versus the chamber radius and proton beam energy...
October 11, 2017: Radiation Protection Dosimetry
Yoomi Choi, Eun-Hee Kim
Assessing the environmental dispersion of radioactive effluents from a nuclear facility under normal operation is a prerequisite in applying for the construction permit and operation license of the facility. In Korea, the Nuclear Safety and Security Commission requires at least 1- and 2-year periods of site-specific meteorological data to assess the atmospheric dispersion of the effluents from a nuclear reactor facility for a construction permit and operating license, respectively. In this study, we investigated if an extended period of meteorological data would be certainly preferable for the prospective assessment of dispersion of the atmospheric effluents under current data handling approaches...
October 10, 2017: Radiation Protection Dosimetry
P Batistoni, R Villari, B Obryk, L W Packer, I E Stamatelatos, S Popovichev, A Colangeli, B Colling, N Fonnesu, S Loreti, A Klix, M Klosowski, K Malik, J Naish, M Pillon, T Vasilopoulou, P De Felice, M Pimpinella, L Quintieri
The design and operation of ITER experimental fusion reactor requires the development of neutron measurement techniques and numerical tools to derive the fusion power and the radiation field in the device and in the surrounding areas. Nuclear analyses provide essential input to the conceptual design, optimisation, engineering and safety case in ITER and power plant studies. The required radiation transport calculations are extremely challenging because of the large physical extent of the reactor plant, the complexity of the geometry, and the combination of deep penetration and streaming paths...
October 5, 2017: Radiation Protection Dosimetry
I Ambrožová, M Davídková, K Pachnerová Brabcová, R V Tolochek, V A Shurshakov
Cosmic radiation consists of primary high-energy galactic and solar particles. When passing through spacecraft walls and astronauts' bodies, the spectrum becomes even more complex due to generating of secondary particles through fragmentation and nuclear interactions. Total radiation exposure is contributed by both these components. With an advantage, space research uses track etched detectors from the group of passive detectors visualizing the tracks of particles, in this case by etching. The detectors can discriminate between various components of cosmic radiation...
September 29, 2017: Radiation Protection Dosimetry
Tatsuhiko Sato, Aiko Nagamatsu, Haruka Ueno, Ryuho Kataoka, Shoko Miyake, Kazuo Takeda, Koji Niita
Estimation of cosmic-ray doses is of great importance not only in aircrew and astronaut dosimetry but also in evaluation of background radiation exposure to public. We therefore calculated the cosmic-ray doses on Earth, Moon and Mars as well as inside spacecraft, using Particle and Heavy Ion Transport code System PHITS. The same cosmic-ray models and dose conversion coefficients were employed in the calculation to properly compare between the simulation results for different environments. It is quantitatively confirmed that the thickness of physical shielding including the atmosphere and soil of the planets is the most important parameter to determine the cosmic-ray doses and their dominant contributors...
September 29, 2017: Radiation Protection Dosimetry
J Lillhök, L Persson, C E Andersen, A Dasu, O Ardenfors
The microdosimetric variance-covariance method was used to study the stray radiation fields from the photon therapy facility at the Technical University of Denmark and the scanned proton therapy beam at the Skandion Clinic in Uppsala, Sweden. Two TEPCs were used to determine the absorbed dose, the dose-average lineal energy, the dose-average quality factor and the dose equivalent. The neutron component measured by the detectors at the proton beam was studied through Monte Carlo simulations using the code MCNP6...
September 29, 2017: Radiation Protection Dosimetry
Wladyslaw Pohorecki, Barbara Obryk
The results of nuclear heating measured by means of thermoluminescent dosemeters (TLD-LiF) in a Cu block irradiated by 14 MeV neutrons are presented. The integral Cu experiment relevant for verification of copper nuclear data at neutron energies characteristic for fusion facilities was performed in the ENEA FNG Laboratory at Frascati. Five types of TLDs were used: highly photon sensitive LiF:Mg,Cu,P (MCP-N), 7LiF:Mg,Cu,P (MCP-7) and standard, lower sensitivity LiF:Mg,Ti (MTS-N), 7LiF:Mg,Ti (MTS-7) and 6LiF:Mg,Ti (MTS-6)...
September 29, 2017: Radiation Protection Dosimetry
Piotr Tulik, Monika Tulik, Maciej Maciak, Natalia Golnik, Damian Kabat, Tomasz Byrski, Jan Lesiak
The aim of this study is to investigate secondary mixed radiation field around linac, as the first part of an overall assessment of out-of-field contribution of neutron dose for new advanced radiation dose delivery techniques. All measurements were performed around Varian Clinic 2300 C/D accelerator at Maria Sklodowska-Curie Memorial, Cancer Center and Institute of Oncology, Krakow Branch. Recombination chambers REM-2 and GW2 were used for recombination index of radiation quality Q4 determination (as an estimate of quality factor Q), measurement of total tissue dose Dt and calculation of gamma and neutron components to Dt...
September 29, 2017: Radiation Protection Dosimetry
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