AN INTEGRATING AIR SAMPLER FOR DETERMINATION OF 222RN

The actual radiological hazard from radon emitted from tailings piles remaining from processing uranium ores is extremely difficult to assess. Exhalation of radon from the ground varies markedly with time and is particularly dependent on the condition of the surface and the prevailing meteorological conditions. Using present techniques, the sampling required to permit a realistic estimate of the dose sustained by a significant population in a year's time is economically prohibitive. A sampler has been developed to collect air continuously at 10 ml/min for 48 hr to provide an integrated sample which can be analyzed to determine the average radon concentration to which people at that location were exposed during the same period of time. A small aquarium aerator pumps filtered air through a precision needle valve with a digital indicating handle into a collapsible 40 1. bag made of laminated 3/4 mil Mylar. The pump can be used either directly from an a.c. line or from a battery with a small power inverter. Each station is resampled at 3-week intervals for a calendar year, amounting to approximately 10% of the total time available. A 1 yr program involving 57 stations in four different cities has been started. © 1969 Health Physics Society.