Radioactivity Monitoring After Dirty Bomb Explosion Simulation

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F70565813%3A_____%2F22%3AN0000011" target="_blank" >RIV/70565813:_____/22:N0000011 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Radioactivity Monitoring After Dirty Bomb Explosion Simulation

Original language description

Two experiments simulating radioactive dirty bomb explosions in an urban area were provided at the National Institute of NBC Protection (SUJCHBO v.v.i.), Czech Republic. A model of a 100 m2 square with four adjacent streets was built in an open space. Its surface was covered with filters to capture radioactive aerosol’ particles after the dirty bomb explosion. A solution containing radionuclide 99mTc of activity ca. 1GBq was dispersed during the experiments using an explosive device. The radionuclide was chosen due to its short half-life, absence of alpha or beta rays and gamma rays of low energy. After the explosion, contaminated filters were collected into measuring vessels and spectra of gamma rays were measured by a hand-held NaI(Tl) spectrometer and laboratory HPGe spectrometers. The ambient dose equivalent rate at measuring vessels was set as well. Two different geometries were used for both detectors: a Marinelli beaker of volume 450 ml, containing a contaminated filter of dimensions 30 x 40 cm, and a gallipot of volume 90 ml, containing a contaminated filter of dimensions 20 x 25 cm. Self-made standards had been prepared by dripping a defined amount of 99mTc solution uniformly on the filters, subsequently inserted into the measuring vessels to set the 99mTc surface activity of measured samples. Measured values of 99mTc surface activity at individual filters, gained by the three above mentioned measurement methods, were recalculated to the time of the explosion and compared. A map of radioactive contamination of the model was set using previously determined filters’ location. The defined amount of 99mTc solution was dripped non-homogenously on some filters, used for self-made standards (i.e. at the filters’ centre or the filters‘ border only) to estimate the impact of non-homogenous filters’ coverage by radioactive aerosol’ particles. The non-homogenous standards 99mTc surface activity deviation from the homogenous standards 99mTc surface activity was determined.

Czech name

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Czech description

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Type

O - Miscellaneous

CEP classification

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OECD FORD branch

10304 - Nuclear physics

Project

<a href="/en/project/VH20182021036" target="_blank" >VH20182021036: Modern methods of detection and identification of dangerous CBRN compounds, methods for decreasing of their danger and decontamination; modern means of persons protection</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů