An evaluation of thoron (and radon) equilibrium factor close to walls based on long-term measurements in dwellings

Thoron gas and its progeny behave quite differently in room environments, owing to the difference in their half-lives; therefore, it is important to measure simultaneously gas and progeny concentrations to estimate the time-integrated equilibrium factor. Furthermore, thoron concentration strongly depends on the distance from the source, i.e. generally walls in indoor environments. In the present work, therefore, measurements of both gas and progeny concentrations were carried out close to the walls, in 43 dwellings located in the Sokobanja municipality, Serbia. Three different types of instruments have been used in the present survey to measure time-integrated gas and progeny concentrations simultaneously. The equilibrium factor for thoron measured “close to the wall”, FTnW, ranged from 0.0014 to 0.077 with GM(GSD) of 0.0060 (2.2), whereas the equilibrium factor for radon, FRn, ranged from 0.06 to 0.95 with GM(GSD) of 0.23 (2.0).

MISHRA R;  ZUNIC Zora S.;  VENOSO Gennaro;  BOCHICCHIO Francesco;  STOJANOVSKA Zdenka;  CARPENTIERI Carmen;  PRAJITH R;  SAPRA B K;  MAYYA Y S;  ISHIKAWA T;  OMORI Y;  VESELINOVIC Nenad C.;  TOLLEFSEN Tore;  UJIC P;  BOSSEW Peter; 

2014-11-25

OXFORD UNIV PRESS

JRC89536

0144-8420,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC89536,   

10.1093/rpd/ncu083,