Thoron versus radon: measurement and dosimetry

Measurement of radon concentration and exhalation rate in some mud houses of district Lahore, Pakistan

“…The concept of D E was launched by the ICRP32 to take into account the biological effects of different types of ionizing radiation by a single index. The exposure from alpha particles of radon and its decay products in terms of effective dose can be determined using the following relation, Equation (2), described by the ICRP33 and UNSCEAR:10 where, C R is the average radon concentration (Bq m −3 ), F is the equilibrium factor equal to 0.4 indoors and 0.6 outdoors have been widely accepted for most of the radon measurements,10 , 12 O is the fraction of time spent in houses: for indoor and outdoor the occupancy factor was 0.7 and 0.3, respectively, both for the male and female based on data obtained from the inhabitants of the understudy mud houses, T is the number of the hours per year, which is equal to 8,760 h y −1 , and F D is the concentration to dose rate conversion factor, which has been estimated to be 9 nGy h −1 per Bq m −3 10 , 34 , 35…”

“…where, C R is the average radon concentration (Bq m À3 ), F is the equilibrium factor equal to 0.4 indoors and 0.6 outdoors have been widely accepted for most of the radon measurements, 10,12 O is the fraction of time spent in houses: for indoor and outdoor the occupancy factor was 0.7 and 0.3, respectively, both for the male and female based on data obtained from the inhabitants of the understudy mud houses, T is the number of the hours per year, which is equal to 8,760 h y À1 , and F D is the concentration to dose rate conversion factor, which has been estimated to be 9 nGy h À1 per Bq m À3 . 10,34,35 The ELCR due to average radon concentration in mud houses was determined using the following relation, Equation (3), as per methodology described by the EPA 21 and adopted by the UNSCEAR: 10…”

Precursory Subsurface 222Rn and 220Rn Degassing Signatures of the 2004 Seismic Crisis at Tenerife, Canary Islands

“…Several analytical methods have been historically used to measure radon and thoron activities: Lucas cells, alpha track films, scintillation method and ionization chamber. Currently it is possible to measure 222 Rn and 220 Rn in high frequency sampling devices based on electrostatic techniques (one measurement per hour or less) (LABRECQUE, 2002;HARLEY et al, 2005) in which an electrostatic potential gradient sweeps the products derived from the decay of the 220 Rn and 222 Rn in the chamber. The 220 Rn and 222 Rn activities are determined by high-resolution alpha spectroscopy of the deposited decay products.…”

Standardization and difficulties of the thoron exhalation rate measurements using an accumulation chamber

“…Nowadays, the significance of thoron has been recognized and interest on the measurement of the indoor thoron concentration is growing (Dwivedi et al, 2005;Pennington, 2006;Harley et al, 2005;Tokonami, 2005;Yonehara et al, 2005). In some cases, when thoron exhalation is high, exposure to thoron may be even higher than exposure to radon .…”