Alpha Scintillation Cells Research Articles

Bureau of Mines Method of Calibrating a Primary Radon Measuring Apparatus.

One important requirement for accurate monitoring of radon in working environments, dwellings, and outdoors is to ensure that the measurement instrumentation is properly calibrated against a recognized standard. To achieve this goal, the U.S. Department of Interior Bureau of Mines (BoM) Radiation Laboratory has participated since 1983 in a program to establish international radon measurement standards. Originally sponsored by the Organization for Economic Cooperation and Development (OECD), the program is also sponsored by the International Atomic Energy Agency. While the National Institute of Standards and Technology (NIST) radium solution ampules are acceptable to all participating laboratories as a primary standard, a method of transferring radon from the NIST source into each laboratory’s primary counting apparatus is a critical problem. The Bureau’s method transfers radon from the primary solution by bubbling 3 L of air through it into a steel cylinder. After homogenizing the radon concentrations in the cylinder, eight alpha-scintillation cells are filled consecutively and measured in a standard counting system. The resulting efficiency is 81.7±1.2%.

Atmospheric radon concentrations in dwellings in Slovenia, Yugoslavia

About 120 homes in Slovenia, Yugoslavia, were selected in urban areas, in a uranium raine and mill region, around coal-fired plants and around a phosphate mill. Radon-222 in air was determined using alpha scintillation cells and the gamma dose rate measured with thermoluminescent dosimeters. The levels obtained were explained by differences in building materials and ventilation rates of homes, as well as by the influence of man-made radioactivity sources. The results show that in the same region radon concentration, expressed as geometric mean, can be up to eight times higher in winter than in the autumn (Pohorje) or nine times higher in one region relative to another (Zirovski vrh - Zasavje).

A method for determination of indoor radon concentrations using α-scintillation cells

Radon air concentrations in dwellings are usually too low to be measured directly by alpha scintillation cells. Thus, a preconcentration of radon from a larger air volume is necessary. A method is described in which air is sampled into a 1.2 dm 3 glass vessel by a simple pump, transported to the laboratory where radon is isolated in a spiral glass tube filled with glass beads cooled with liquid nitrogen, and then transferred to a 180 cm 3 alpha scintillation cell and counted. Using this method radon was determined in some selected homes in different regions of Slovenia, Yugoslavia.