Naslov
A CASE STUDY OF THE FIRST REMEDIATION OF ELEVATED RADON LEVELS IN ONE PUBLIC BUILDING IN CROATIA

Autori
Radolić, Vanja ; Poje Sovilj, Marina ; Navratilova Rovenska, Katerina ; Fojtikova, Ivana ; Stanić, Denis ; Miklavčić, Igor

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Zbornik sažetaka 13. Simpozija Hrvatskog društva za zaštitu od zračenja / Petrinec, Branko ; Pavelić, Luka ; Popić, Jelena ; Kopjar, Nevenka - Zagreb : Hrvatsko društvo za zaštitu od zračenja, 2023, 128-128

Skup
13. Simpozij Hrvatskog društva za zaštitu od zračenja

Mjesto i datum
Poreč, Hrvatska, 18.04.2023. - 21.04.2023

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Domaća recenzija

Ključne riječi
radon concentration ; remediation ; public building

Sažetak
Radon concentrations in 117 schools and 87 kindergartens of Istria county were systematically measured by track-etched detectors from November 2013 until February 2015. Detectors were exposed for one year in every playroom in kindergartens and selected classrooms and offices evenly distributed across areas and floors in schools. The obtained average radon concentrations were higher than the reference value (300 Bq/m^3) in 15.5% of kindergartens and 21.0% of schools including this elementary school of interest in Pula. In this school building integrated follow-up radon measurements were performed in 2018-19 by track-etched detectors exposed in every classroom and office. Simultaneously, continuous radon measurements were conducted by TSR3 radon detectors which were exposed for several weeks during the heating season and the time resolution was adjusted to 1-hour. The observed daily variations of radon concentrations show a strong dependence on increased natural ventilation during working hours ; a significantly decrease of radon concentrations in the morning and early afternoon and a consequently increase at night and during weekends. However, increased natural ventilation reduce radon concentration in the building during working hours only by 15% and therefore, the design and application of some more effective radon reduction techniques were suggested. The project of radon mitigation has been proposed in September 2021 by one architectural bureau and realized in spring 2022. At six locations around the school building, radon sumps have been created underground beneath the building which serve as the lowest pressure points in the ground to collect radon gas from the soil rather than it being drawn into the building. The pipeworks and inline fans have been installed on the outside walls of the building to continuously exhaust radon from the sump into the atmosphere outside the building. The effectiveness of the installed system has been checked during the IAEA regional workshop on the best practices for reducing radon concentrations in buildings held in Pula in November 2022. During three days, 25 continuous radon monitors (RadonEye Plus 2, Corentium Pro, Tesla TSR4 and AlphaGUARD) were exposed across areas and floors in the school building. Results of this short term measurement show that when the system was fully operable (all fans are switched on) radon concentrations were reduced to levels well below 200 Bq/m^3 ; when fans were switched off, radon concentrations rapidly increased. Optimization of the installed system for energy- saving purposes was recommended.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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