A study of radon emitted from building materials using plastic α-track detectors

Abstract

Films made from cellulose nitrate LR-115 (Pathé Kodak) and CR-39 have been used for long-term measurements of the radon-222 emanation from building materials and the resultant activity inside houses. The emanation from crushed granite bricks is found to be produced from within the brick while in the clay bricks it originates in the surface layers only. The airborne radon activity inside houses constructed from clay brick is found on average to be 22 mBq 1-1 (0.57 pCi 1-1) while inside a closed vessel sealed to the brick the average equilibrium activity is 40 mBq 1-1 pCi 1-1).

Study of Indoor Radon, Thoron, Their Progeny Concentration and Radon Exhalation Rate in the Environs of Mohali, Punjab, Northern India

“…The radon exhalation rates of soil samples were measured by closed canister techniques (Abu-Jarad et al, 1980;Khan et al, 1992;Singh et al, 1997;Kumar et al, 2003;Mahur et al, 2013). The soils samples collected from the dwellings and other areas under study were dried and sieved through a 100-mesh sieve and 100 g was placed in the canisters similar to those used in the calibration experiment of Singh et al (1997) and were sealed.…”

Indoor radon monitoring in some buildings surrounding the national Hydroelectric Power Corporation (NHPC) project at upper Siang in Arunachal Pradesh, India

“…LR-115 type-II films are sensitive to = particles of energy range 0.1 to 4 MeV and are unaffected by electrons, X-rays and C-rays [5]. Due to its being sensitive to only a specific range of energy, it is ideal for the use as radon dosimeter even in bare mode as it is free from plate out effect [6].…”

Radon Exhalation Rates and Radium Estimation Studies in Soil Samples Collected from Various Locations in the Environment of Shahjahanpur District of Uttar Pradesh, India

“…For the measurement of radon exhalation rates and radium content from soil samples ""Sealed Can Technique"" has been used ( [11], [12], [13], [14]). The amount of radon emanated from a given sample per unit mass is known as mass exhalation rate and surface area per unit time is known as surface exhalation rate.…”

“…After drying, samples were sieved to obtain the fine quality of samples. About 130 gm (130 x10 −3 kg) of sample was enclosed in a plastic "cylindrical can" ( [11], [12], [16]) and sealed for a period of four weeks in order to get equilibrium between radium and radon. After that the LR-115 type-II plastics track detector of size 2cm x 2cm was fixed on the bottom of the lid of each can having dimension 8cm in total height and 7cm in diameter such that the sensitive side of the detector always faced the soil sample as shown in figure 2.…”