scholarly journals Occupational exposure to Am-Be neutron calibration source mounted in OB26 shielding container

Nukleonika ◽  
2014 ◽  
Vol 59 (3) ◽  
pp. 97-103 ◽  
Author(s):  
Kamil Szewczak ◽  
Slawomir Jednorog
Keyword(s):  
Occupational Exposure ◽  
Reference Points ◽  
Radiological Protection ◽  
Individual Dose ◽  
Control Room ◽  
Dose Equivalent ◽  
Calibration Source ◽  
Equivalent Rate ◽  
Ambient Dose Equivalent ◽  
Ambient Dose

Abstract Laboratory for Dosimetric and Radon Instruments Calibration which is a part of Central Laboratory for Radiological Protection (CLRP) in Warsaw is equipped with 241Am-Be neutron calibration source with activity of 185 GBq since 1999. The capsule was mounted in the OB26 type shielding container. The control room is separated from the above source by a concrete wall of 0.5 m in thickness. The calibration hall is adjacent to one side of the offi ce room. To comply with the requirements of the radiological protection system, the occupational exposure of persons that are working both in the offi ce and control room needs to be assessed. Two methods were involved for ambient dose equivalent rate determination. The active instrument measurements (AIMs) performed with the Berthold LB6411 neutron probe and the Monte Carlo simulation method (MCS) based on MCNP5 code. These estimations were completed for fi ve reference points. Additionally the γ radiation component was measured by RSS131 ionisation chamber. An increased value of the ambient dose equivalent rate from neutrons was observed in two reference positions. The fi rst observation was done in the control room while the second one in the offi ce room. Expected individual dose equivalents were evaluated based on the results of the AIM and on the expected working time in particular reference points. The annual individual dose equivalent associated with calibration activities using mentioned neutron source was estimated at maximum 0.8 mSv.

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.

scholarly journals Calculating radiation dose rate from online real-time environmental -spectrum using NaI(Tl) detector

2021 ◽  
Vol 11 (1) ◽  
pp. 16-25
Author(s):  
Thu Bac Vuong ◽  
Hoang Tuan Truong ◽  
Duc Thang Duong ◽  
Dac Dung Bui ◽  
Duc Viet Cao ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Dose Rate ◽  
Real Time ◽  
Specific Activity ◽  
Radioactive Isotopes ◽  
Dose Equivalent ◽  
Radiation Dose Rate ◽  
Equivalent Rate ◽  
Ambient Dose Equivalent ◽  
Ambient Dose

Calculating gamma radiation dose rate from online real-time environmental gamma spectrum using NaI(Tl) detector has been developed into a software named RADAPROC V.1 in the Center for Operating the National Network of Environmental Radiation Monitoring And Warning (CONNERMAW). Currently, hundreds of online gamma spectra per day from online monitoring stations are processed to calculate the total ambient dose equivalent rate and the ambient dose equivalent rate of typical natural radioactive isotopes such as K-40, Bi-214, Tl-208 according to the method of using the function G(E) and the photo-peak area method. The calculated results have been compared with the results of calculating the dose rate from the specific activity of radioactive isotopes in soil samples collected at the same monitoring location and analyzed in the laboratory. The difference between the methods is less than 25%. The ambient dose equivalent rates of typical natural radioactive isotopes are a bit higher than those calculated with SARA-NMC software. The software will be improved shortly for better results.

Sign in / Sign up

Export Citation Format

Share Document