12 research outputs found
Recommended Corrective Security Measures to Address the Weaknesses Identified Within the Shapash Nuclear Research Institute
The Shapash Nuclear Research Institute (SNRI) data book was issued by the International Atomic Energy Agency (IAEA) in 2013. The hypothetical facility data book describes the hypothetical site, which is divided into two areas: the low-security area, known as the administrative area, and the very high-security area, known as the protected area. The book contains detailed descriptions of each area’s safety and security measures, along with figures of multiple buildings in both areas, and also includes information about the site’s computer networks.
This paper aims to identify security weaknesses related to the institute’s location, the Administrative Area (AA), the Protected Area (PA), and the Instrumentation and Control Technology system (ICT) within the SNRI and proposes corrective actions to improve the site’s security measures against malicious acts, based on the IAEA nuclear security series publications, and ultimately proposes a new layout for the whole site and the research reactor building presenting the changes made, using a software called Edraw Max
Volumic activities measurements and equivalent doses calculation of indoor 222Rn in Morocco
Purpose: As a way of prevention, we have measured the volumic activities of indoor 222Rn and we have calculated the corresponding effective dose in some dwellings and enclosed areas in Morocco. Seasonal variation of Radon activities and Relationships between variation of these activities and some parameters such height, depth and type of construction were also established in this work.Methods: The passive time-integrated method of using a solid state nuclear track detector (LR-115 type II) was employed. These films, cut in pieces of 3.4 ´ 2.5 cm2, were placed in detector holders and enclosed in heat-scaled polyethylene bags.Results: The measured volumic activities of radon vary in houses, between 31 and 136 Bq/m3 (0.55 and 2.39 mSv/year) with an average value of 80 Bq/m3 (1.41 mSv/year). In enclosed work area, they vary between 60 Bq/m3 (0.38 mSv/year) in an ordinary area to 1884 Bq/m3 (11.9 mSv/year) at not airy underground level of 12 m. the relatively higher volumic activities of 222Rn in houses were measured in Youssoufia and khouribga towns situated in regions rich in phosphate deposits. Measurements at the geophysical observatory of Berchid show that the volumic activity of radon increases with depth, this is most probably due to decreased ventilation. Conclusion: The obtained results show that the effective dose calculated for indoor dwellings are comparable to those obtained in other regions in the word. The risks related to the volumic activities of indoor radon could be avoided by simple precautions such the continuous ventilation. The reached high value of above 1884 Bq/m3 don't present any risk for workers health in the geophysical observatory of Berchid because workers spend only a few minutes by day in the cellar to control and reregister data
Measurement of radium isotope activities in reservoir and spring water in the Cameroon Central Region
Purpose: To determine the activities of 226Ra and 228Ra in the reservoir and spring water samples respectively during the dry and the rainy seasons; and to calculate the annual intake Ii (Bq/y) for each type of water samples. Methods: Using both well calibrated Canberra NaI(Tl) and HPGe detector systems, it was possible to determine the average specific activity of those radium’s isotopes in water samples which were collected in 2010, from Reservoirs and springs in Cameroon central region including Ngoaekelle, Minboman, Etoudi and Njoungolo. Results: The average specific activity values obtained for 226Ra and 228Ra in reservoir water samples were 8.76 ± 3.50 BqL-1 and 0.64 ± 0.28 BqL-1 during the dry season and, 8.24 ±3.48 BqL-1 and 0.58 ± 0.24 BqL-1 during the rainy season respectively. For spring water, the average values were 3.50 ± 0.63 BqL-1 and below 0.0002 BqL-1 (detection limit of 228Ra in water) during the dry season; 3.20 ± 0.60 BqL-1 and below 0.0002 BqL-1 (detection limit of 228Ra in water) during the rainy season respectively. Assuming that the volume of drinking water for adult is 2.5 litres per day, the average annual intakes of 226Ra and 228Ra through ingestion in these water samples were 7702 Bq/y and 575 Bq/y for reservoir water; 2993 Bq/y and < 0.25 for spring water respectively. Conclusion: The results have indicated that the annual intake by the population of sampling region as a result of 226Ra in these drinking waters is 7.7 × 103Bq/y more than the maximum limit fixed by ICRP which is 7 × 103 Bq/y. There is a need for regular monitoring the radiological water quality aspect in this region
Difficulties in dating Pleistocene marine levels using fossil mollusk shells: the Ouljian level on the High Atlas shore, Morocco
In order to comprehend the difficulty of dating
marine strata using samples of mollusks shells and in an attempt to establish criteria that help in judging
the validity of a 230Th /234U age determination, we present here the results of a radioactive element
analysis of some 80 samples of mollusk shells. The shells were taken from fossil marine beaches between
4 and 8 meters above current sea level. When compared with the Egyptian shore of the Red Sea
these levels are taken to be related to climate stage 5 dated as about 122,000 years ago. The ages
obtained are often rejuvenated regardless of site, the incidence of calcite, the amount of uranium and
the relationships of 234U/238U.
Unlike coral, mineralogical criteria cannot be used to select mollusk shells unaffected by recrystallization,
for present-day shells may be composed of aragonite, others are calcitic, and others contain both
minerals. In any case, the rules concerning their effects of composition on radioactivity are as yet poorly
understood. With these problems in mind, we made multiple analyses on several species of of mollusks,
always collected from the same sites, in order to understand progressive changes in the process
of age rejuvenation and to attempt eventually to determine systematic criteria providing information on
the validity of the calculated age. Possible mechanisms that may influence the incorporation of uranium
in rejuvenation have been conceived and are discussed.Afin de comprendre la difficulté de datation des niveaux marins à l'aide des échantillons de
coquilles de mollusques et d'essayer d'établir des outils méthodologiques pouvant aider à juger de la
validité d'un âge 230Th /234U, nous confrontons 80 analyses radiochimiques d'échantillons de coquilles
de mollusques prélevés dans des plages marines fossiles situées entre 4 et 8 m par rapport au niveau
de l'eau actuel. les niveaux où ont été faits les prélèvements, analogues à ceux de la côte égyptienne
de la Mer Rouge, sont sensés appartenir au stade climatique 5e daté à 122 ka environ. On note que les
âges obtenus sont souvent rajeunis indépendamment du site, du taux de calcite, de la teneur en uranium
et du rapport 234U/238U.
Contrairement aux échantillons de coraux, le critère minéralogique ne peut pas être utilisé pour choisir
les échantillons non recristallisés, certaines coquilles de mollusques actuelles sont en aragonite, d'autres
sont en calcite et d'autres contiennent les deux formes sans que les rapports de proportion en
soient encore bien connus. Devant cette situation, nous avons multiplié les analyses sur des échantillons
de coquilles de mollusques appartenant à plusieurs espèces prélevés aux mêmes endroits afin de
comprendre le scénario de rajeunissement des âges et d'essayer d'établir éventuellement des critères
méthodologiques pouvant nous renseigner sur la validité de l'âge calculé. Des scénarios sur le mode
d'incorporation de l'uranium et son rôle dans le rajeunissement de l'âge ont été également imaginés et
discutés
Uranium and radium activities measurements and calculation of effective doses in some drinking water samples in Morocco
Purpose: As a way of prevention, we have measured the activities of uranium and radium isotopes (234U, 238U, 226Ra, 228Ra) for 30 drinking water samples collected from 11 wells, 9 springs (6 hot and 3 cold), 3 commercialised mineral water, and 7 tap water samples. Methods: Activities of the Ra isotopes were measured by ultra-gamma spectrometry using a low background and high efficiency well type germanium detector. The U isotopes were counted in an alpha spectrometer.Results: The measured Uranium and radium activities are similar to those published for other non-polluting regions of the world. Except in one commercialised gaseous water sample, and in two hot spring water samples, the calculated effective doses during one year are inferior to the reference level of 0.1 mSv/year recommended by the International Commission on Radiological Protection. Conclusion: These activities don't present any risk for public health in Morocco. The sparkling water of Oulmes is occasionally consumed as table water and waters of warm springs are not used as main sources of drinking water.
The INSEN Experience, by INSEN Chairs
As a feature of this issue, we asked INSEN chairs to share their thoughts about what the organization has meant to them as they led this network of colleagues in the mission of improving nuclear security education and training at institutions and organizations around the world.
Below are their stories. The chairs describe their paths to INSEN leadership, the organization’s work, challenges, and successes, and how the experience of leading INSEN affected their professional and personal lives. IJNS thanks each of the authors contributing to this collaborative article.
Every chair has done a tremendous job in their tenure as INSEN’s leader—and we, the membership and all who have benefitted from their dedication and expertise, are deeply grateful. We look forward to INSEN’s next decade under the leadership of colleagues and friends like these
Distribution of the Rare Earth Elements in the Sediments of the Bouregreg River (Morocco) Using the Instrumental Neutron Activation Analysis (INAA).
Rare earth elements (REE), define a group of fifteen chemical elements
from lanthanum to lutetium (atomic numbers 57-71) characterized by
similar chemical properties. To study their distribution in sediment
samples of the Bouregreg river and its tributaries, 10 sampling sites
have been chosen. The collected sediment samples were analysed by
instrumental neutron activation analysis (INAA) using the Orph\ue9e
and Osiris reactors of CEA Saclay (France). The chondritic
normalisation curves show enrichment in light rare earth elements
(LREE), a negative Eu anomaly in several samples, and a progressive
depletion of heavy rare earth elements (HREE). Two hypotheses are
discussed: the nature of parent rocks of these sediments and the
phisico-chemical conditions of sedimentation especially complexation
and oxydo-reduction phenomenons
A potential groundwater aquifer for palaeoclimate reconstruction: Turonian aquifer, Tadla basin, Morocco
K
Volumic activities measurements and equivalent doses calculation of indoor 222Rn in Morocco
Purpose: As a way of prevention, we have measured the volumic activities of indoor 222Rn and we have calculated the corresponding effective dose in some dwellings and enclosed areas in Morocco. Seasonal variation of Radon activities and Relationships between variation of these activities and some parameters such height, depth and type of construction were also established in this work.Methods: The passive time-integrated method of using a solid state nuclear track detector (LR-115 type II) was employed. These films, cut in pieces of 3.4 ´ 2.5 cm2, were placed in detector holders and enclosed in heat-scaled polyethylene bags.Results: The measured volumic activities of radon vary in houses, between 31 and 136 Bq/m3 (0.55 and 2.39 mSv/year) with an average value of 80 Bq/m3 (1.41 mSv/year). In enclosed work area, they vary between 60 Bq/m3 (0.38 mSv/year) in an ordinary area to 1884 Bq/m3 (11.9 mSv/year) at not airy underground level of 12 m. the relatively higher volumic activities of 222Rn in houses were measured in Youssoufia and khouribga towns situated in regions rich in phosphate deposits. Measurements at the geophysical observatory of Berchid show that the volumic activity of radon increases with depth, this is most probably due to decreased ventilation. Conclusion: The obtained results show that the effective dose calculated for indoor dwellings are comparable to those obtained in other regions in the word. The risks related to the volumic activities of indoor radon could be avoided by simple precautions such the continuous ventilation. The reached high value of above 1884 Bq/m3 don't present any risk for workers health in the geophysical observatory of Berchid because workers spend only a few minutes by day in the cellar to control and reregister data.</p
Measurement of radium isotope activities in reservoir and spring water in the Cameroon Central Region
Purpose: To determine the activities of 226Ra and 228Ra in the reservoir and spring water samples respectively during the dry and the rainy seasons; and to calculate the annual intake Ii (Bq/y) for each type of water samples. Methods: Using both well calibrated Canberra NaI(Tl) and HPGe detector systems, it was possible to determine the average specific activity of those radium’s isotopes in water samples which were collected in 2010, from Reservoirs and springs in Cameroon central region including Ngoaekelle, Minboman, Etoudi and Njoungolo. Results: The average specific activity values obtained for 226Ra and 228Ra in reservoir water samples were 8.76 ± 3.50 BqL-1 and 0.64 ± 0.28 BqL-1 during the dry season and, 8.24 ±3.48 BqL-1 and 0.58 ± 0.24 BqL-1 during the rainy season respectively. For spring water, the average values were 3.50 ± 0.63 BqL-1 and below 0.0002 BqL-1 (detection limit of 228Ra in water) during the dry season; 3.20 ± 0.60 BqL-1 and below 0.0002 BqL-1 (detection limit of 228Ra in water) during the rainy season respectively. Assuming that the volume of drinking water for adult is 2.5 litres per day, the average annual intakes of 226Ra and 228Ra through ingestion in these water samples were 7702 Bq/y and 575 Bq/y for reservoir water; 2993 Bq/y and < 0.25 for spring water respectively. Conclusion: The results have indicated that the annual intake by the population of sampling region as a result of 226Ra in these drinking waters is 7.7 × 103Bq/y more than the maximum limit fixed by ICRP which is 7 × 103 Bq/y. There is a need for regular monitoring the radiological water quality aspect in this region.</p