US EPA

1435582 

Journal Article 

Concentration of radon, thoron and their progeny levels in different types of floorings, walls, rooms and building materials 

Sathish, LA; Nagaraja, K; Ramanna, HC; Nagesh, V; Sundareshan, S 

2009 

7 

1 

1-9 

WOS:000283803800001 

Background: Radon, thoron and their progenies are the most
important contributions to human exposure from natural sources. Radon exists in soil gas,
building materials, Indoor atmosphere etc. Among all the natural sources of radiation dose to
human beings, inhalation of radon contributes a lot. The work presented here emphasizes the long
term measurements of radon, thoron and their progeny concentrations in about 100 dwellings using
solid state nuclear track detectors. Materials and Methods: Measurements were made using
dosimeters and the concentrations were estimated by knowing the track density of films through
spark counter, and sensitivity factor for bare, filter and membrane films. Results: Presence of
radon and thoron in houses is the effect of several aspects such as the activity concentrations
of uranium, radium and thorium in the local soil, building materials, ventilation of houses and
also entry of radon into houses through the cracks in floor/wall. Conclusion: The observations
reveal that the concentrations of radon and/or thoron are relatively higher in granite than in
concrete, cement and bricks. In continuation to this the concentration observed in bathrooms is
more compared to kitchen, bedroom and living rooms. This study discloses that the residential
rooms of good ventilation will avoid the health hazards due to radon and its rich materials.
Iran. J. Radiat. Res., 2009; 7 (1): 1-9 

SSNTDs; radon; thoron; dosimeter; building materials