|M.Sc Student||Russo Olga|
|Subject||Testing of Radon Exhalation Rate from Building Materials|
|Department||Department of Quality Assurance and Reliability||Supervisor||Professor Konstantin Kovler|
The present study deals with radioactivity of building materials and different methods of measurement of the radon exhalation rate.
Radon is formed as a result of natural radioactive decay of uranium; therefore radon is in high concentration in the ground and in rock containing radioactive elements. In open spaces its concentration is low, but inside closed spaces (such as dwellings) it accumulates. Its level in an apartment is determined both by the composition of the building materials and radon’s concentration in the ground under the building.
A high level of radon in dwellings is considered as a health hazard. In this connection, effective measures for protection of dwellings against radon have to be taken already at the design stage, and building materials have to be subjected to strict radiation control.
The purpose of the work is to review the state of the art in the area of measurements of radioactivity and exhalation properties of different building materials and components, experimentally to study the process of radon exhalation from concrete, pumice blocks and specimens of hardened cement paste, in which part of the cement has been substituted by fly ash, and to compare different methods of measuring the radon exhalation rate from building materials.
As radon is both invisible and odorless, special equipment is needed for it detection. In our experiments three radon detection methods were used: the electrostatic electrets chamber (Integrated Measurement Method), the activated charcoal detector (Integrated Measurement Method) and the solid state alpha spectrometer RAD-7 (Continuous Monitoring Method).