scholarly journals Characterization of an ²⁴¹Am-Be neutron irradiation facility at Institute for Nuclear Science and Technology

2021 ◽  
Vol 7 (2) ◽  
pp. 16-24
Author(s):  
Ngoc Toan Tran ◽  
Vu Long Chu ◽  
Duc Ky Bui ◽  
Duc Kien Nguyen ◽  
Duc Tam Nguyen
Keyword(s):  
Science And Technology ◽  
Neutron Field ◽  
Dose Equivalent ◽  
Neutron Fluence Rate ◽  
Nuclear Science ◽  
Equivalent Rate ◽  
Ambient Dose Equivalent ◽  
Spectral Unfolding ◽  
Ambient Dose

An automated panoramic irradiator with a 241Am-Be neutron source of 5 Ci is installed in a bunker-type medium room at the Institute for Nuclear Science and Technology (INST) for calibration of neutron devices. Bonner Sphere Spectrometer (BSS) formed by 6 spheres plus bare detector, with cylindrical, almost point like, 6LiI(Eu) scintillator and 2 different spectral unfolding FRUIT and BUNKIUT codes are used to characterize the neutron field in different measurement points along the irradiation bench. The neutron field is also simulated by MCNP5 software and compared with measurements performed by the BSS. The paper shows the main results obtained in terms of neutron spectra at fixed distances from the source as well as their neutron fluence rate (totaland direct) and ambient dose equivalent rate. These values measured by the BSS with two unfolding FRUIT and BUNKIUT codes are in good agreement with that of simulated by MCNP5 within 10%.

scholarly journals Neutron calibration field at Institute for Nuclear Science and Technology

2016 ◽  
Vol 6 (4) ◽  
pp. 1-7
Author(s):  
Ngoc Thiem Le ◽  
Ngoc Quynh Nguyen ◽  
Quang Tuan Ho ◽  
Van Giap Trinh ◽  
Tuan Khai Nguyen ◽  
...  
Keyword(s):  
Theoretical Calculations ◽  
Science And Technology ◽  
Free Field ◽  
Dose Equivalent ◽  
Nuclear Science ◽  
Bonner Sphere ◽  
Ambient Dose Equivalent ◽  
Bonner Sphere Spectrometer ◽  
Ambient Dose ◽  
Good Agreement

In this study, a neutron calibration field of a 241Am-Be standard source at the Institute for Nuclear Science and Technology is characterized in terms of neutron spectral fluxes and neutron ambient dose equivalent ( ) rates based on ISO 8529 recommended generalized fit method together with measurements using a Bonner Sphere Spectrometer and MAXED unfolding techniques. The total, direct and scattered neutron components as well as rates and neutron spectral fluxes are separated from each other. The direct  rates and neutron spectral fluxes in the free field as functions of distances from the source are also theoretically calculated based on the neutron source strength. The comparison between experimental data and theoretical calculations of the  rates and neutron spectral fluxes shows good agreement within 3%, this has confirmed the reliability of the field characterization process and its applicability in the practical calibration works for neutron survey meters.

scholarly journals Study of the screening survey using an ambient dose equivalent rate survey meter in criticality accidents

2019 ◽  
Vol 6 (0) ◽  
pp. 152-155
Author(s):  
Katsuya Hoshi ◽  
Norio Tsujimura ◽  
Tadayoshi Yoshida ◽  
Osamu Kurihara ◽  
Eunjoo Kim ◽  
...  
Keyword(s):  
Dose Equivalent ◽  
Equivalent Rate ◽  
Ambient Dose Equivalent ◽  
Criticality Accidents ◽  
Screening Survey ◽  
Ambient Dose

Correction Coefficients for Measuring the Ambient Dose Equivalent Rate of Neutrons

ANRI ◽  
2021 ◽  
Vol 0 (4) ◽  
pp. 32-40
Author(s):  
Alexander Alexeev ◽  
Vladimir Pikalov ◽  
Pavel Alexeev
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Dose Equivalent ◽  
Equivalent Rate ◽  
Ambient Dose Equivalent ◽  
Ambient Dose

Calculations of the response for the most widely used neutron dosimeters at the Russian nuclear power plant (NPP) have been performed. It is shown that in some cases it is necessary to introduce a correction for the measured value of the ambient dose equivalent rate (AEDR). The experimentally tested values of the correction for measuring AEDR in the containment rooms of NPP with VVER-1200 are given.

scholarly journals Indoor Radon Measurements Using Radon Track Detectors and Electret Ionization Chambers in the Bauxite-Bearing Areas of Southern Adamawa, Cameroon

2020 ◽  
Vol 17 (18) ◽  
pp. 6776
Author(s):  
Saïdou ◽  
Oumar Bobbo Modibo ◽  
Ndjana Nkoulou II Joseph Emmanuel ◽  
Olga German ◽  
Kountchou Noube Michaux ◽  
...  
Keyword(s):  
Indoor Radon ◽  
Geometric Mean ◽  
Reference Level ◽  
Dose Equivalent ◽  
Ionization Chambers ◽  
The Public ◽  
Average Value ◽  
Equivalent Rate ◽  
Ambient Dose Equivalent ◽  
Ambient Dose

The current work deals with indoor radon (222Rn) concentrations and ambient dose-equivalent rate measurements in the bauxite-bearing areas of the Adamawa region in Cameroon before mining from 2022. In total, 90 Electret Ionization Chambers (EIC) (commercially, EPERM) and 175 Radon Track Detectors (commercially, RADTRAK2) were used to measure 222Rn concentrations in dwellings of four localities of the above region. A pocket survey meter (RadEye PRD-ER, Thermo Scientific, Waltham, MA, USA) was used for the ambient dose-equivalent rate measurements. These measurements were followed by calculations of annual doses from inhalation and external exposure. 222Rn concentrations were found to vary between 36 ± 8–687 ± 35 Bq m−3 with a geometric mean (GM) of 175 ± 16 Bq m−3 and 43 ± 12–270 ± 40 Bq m−3 with a geometric mean of 101 ± 21 Bq m−3 by using EPERM and RADTRAK, respectively. According to RADTRAK data, 51% of dwellings have radon concentrations above the reference level of 100 Bq m−3 recommended by the World Health Organization (WHO). The ambient dose equivalent rate ranged between 0.04–0.17 µSv h−1 with the average value of 0.08 µSv h−1. The inhalation dose and annual external effective dose to the public were assessed and found to vary between 0.8–5 mSv with an average value of 2 mSv and 0.3–1.8 mSv with an average value of 0.7 mSv, respectively. Most of the average values in terms of concentration and radiation dose were found to be above the corresponding world averages given by the United Nations Scientific Commission on the Effects of Atomic Radiation (UNSCEAR). Even though the current exposure of members of the public to natural radiation is not critical, the situation could change abruptly when mining starts.

Aircraft crew radiation workplaces: Comparison of measured and calculated ambient dose equivalent rate data using the EURADOS in-flight radiation data base

2006 ◽  
Vol 118 (2) ◽  
pp. 182-189 ◽  
Author(s):  
Peter Beck ◽  
David Bartlett ◽  
Lennart Lindborg ◽  
Ian McAulay ◽  
Klaus Schnuer ◽  
...  
Keyword(s):  
Data Base ◽  
Rate Data ◽  
Dose Equivalent ◽  
Radiation Data ◽  
Equivalent Rate ◽  
Ambient Dose Equivalent ◽  
Ambient Dose

scholarly journals Ambient dose equivalent rate and soil contamination density with 137Cs in kitchen gardens in settlements of the Bryansk region, Russia in 2020–2021

2021 ◽  
Vol 14 (4) ◽  
pp. 85-95
Author(s):  
V. P. Ramzaev ◽  
A. N. Barkovsky ◽  
A. A. Bratilova
Keyword(s):  
Soil Contamination ◽  
Natural Radionuclides ◽  
Mean Value ◽  
Dose Equivalent ◽  
Kitchen Garden ◽  
Equivalent Rate ◽  
Kitchen Gardens ◽  
Ambient Dose Equivalent ◽  
Ambient Dose

The article provides results of application of the field (in situ) gamma spectrometry method for carrying out mass monitoring measurements of ambient dose equivalent rate and soil contamination density with 137Cs in kitchen garden plots located in the zone of radioactive contamination after the Chernobyl accident. In 2020 and 2021, 115 private farmsteads in 46 settlements of the Bryansk region were surveyed. At the time of the survey, the officially established average density of soil contamination with 137Cs in the settlements ranged from 27 to 533 kBq/m2 . The field spectra were measured using a portable scintillation gamma-spectrometer-dosimeter. Results of the field measurements and subsequent calculations of soil contamination density with 137Cs in the kitchen gardens were in good agreement with official data on the average soil contamination density with 137Cs in the surveyed settlements. The mean value of the ratio of the experimental data to the official data was 1.04. Individual values of experimental data deviated from corresponding official values by no more than two times. The use of the gamma spectrometry method in situ made it possible: 1) to determine separately values of the ambient dose equivalent rate from 137Cs and from natural radionuclides in the soil, and 2) to estimate the effective external doses to a person who worked in the kitchen gardens. The measured values of ambient dose equivalent rate varied from 17 to 53 nSv/h (mean ± standard deviation = 35 ± 9 nSv/h) for natural radionuclides and from 8 to 432 nSv/h (mean ± standard deviation = 125 ± 91 nSv/h) for 137Cs. The ambient dose equivalent rate from 137Cs normalized to the soil contamination density with 137Cs in the same kitchen garden was in the range of 0.41–0.84 (nSv/h)/(kBq/m2 ) with a mean value of 0.55 (nSv/h)/(kBq/m2 ). If a person stayed in kitchen garden for 840 hours per year, the estimated effective external doses from natural radionuclides and 137Cs were respectively in the range of 0.008–0.025 mSv/year and 0.004–0.20 mSv/year.

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