This study examined correlations between radon, thoron and thoron progeny concentrations based on surveys conducted in several different countries. For this purpose, passive detectors developed or modified by the National Institute of Radiological Sciences (NIRS) were used. Radon and thoron concentrations were measured using passive discriminative radon-thoron detectors. Thoron progeny measurem...

Radon, radon progeny and unattached radon progeny were measured in two chambers with different characteristics at the Jenolan Caves, New South Wales, Australia, in 1996. Meteorological parameters and condensation nucleus concentrations were measured in order to understand the processes governing the radon concentration and degree of disequilibrium with the progeny. One chamber was poorly ventil...

The lung dose derived from radon is not attributed to the radon gas itself, but instead to its short-lived progeny. However, in many epidemiological studies as well as in case control studies of the radon risk, the excess number of cancers are related to the radon gas exposure, and not to the radon progeny exposure. A justification for such an approach has resorted to the assumption that there ...

In recent years, a number of case-control epidemiological studies have taken place and others are in progress to evaluate the lung cancer risk to the general population from exposure to radon and its short-lived progeny in the indoor residential environment. While it is actually long term exposure over past decades to radon progeny by inhalation that dominates lung doses, for a number of practi...

Liquid Scintillation Counting (LSC) is a measuring technique, broadly applied in environmental monitoring of different radionuclides. One of the possible applications of LSC is the measurement of radon and thoron progeny. There are certain advantages of this method, especially high counting efficiency for alpha and beta particles emitted by radon and thoron progeny. This advantage has been poin...

Background: The potential hazards of exposure to radiation from radon have been of great concern worldwide, as it is associated with an increased risk of lung cancer. Radon (222Rn) and its progeny are the main sources of radioactivity in the environment. The half-life of 222Rn (3.82 days) is long enough for it to diffuse into and build up in homes. 220Rn or thoron from the 232Th series, and 219...

Among radiation exposure pathways to human beings, inhalation dose is the most prominent one. Radon, thoron, and their progeny contribute more than 50 per cent to the annual effective dose due to natural radioactivity. South west coast of India is classified as a High Natural Background Radioactivity Area and large scale data on natural radioactivity and dosimetry are available from these coast...

Inhalation of Rn progeny has been recognized as a health risk, primarily as a cause of human lung cancer. Rn progeny in the domestic environment contributes the greatest fraction of the natural radiation exposure to the public. The ultrafine activity of these progeny amounts up to about 10 percent of the total activity (attached and ultrafine), but is considered to yield about 50 percent of the...

Radon and progeny ((218)Po, (214)Pb, (214)Bi and (214)Po) in thermal spas are well known radioactive pollutants identified for additional radiation burden of patients due to the activity concentration peaks which appear during bath treatment or due to drinking of waters of high radon content. This burden affects additionally the working personnel of the spas. The present paper has focused on th...

Radon-222 (also known as radon) is a relatively long-lived isotope of radon and originates from uranium present in the earth's crust. Radon-220 (also known as thoron) is a short-lived isotope of radon and originates from thorium present in the earth's crust. Fundamental properties and health hazards of these gases are compared. On the average, the thoron contribution to the total dose to the lu...