Data-acquisition System for Radon Monitoring.
Franklin-JC; Zawadzki-RJ; Meyer-TO; Hill-AL
NTIS: PB 250 739 :19 pages
A data-acquisition system was designed by the Bureau of Mines to monitor five detectors with radon continuously flowing through each. These detectors could be monitored up to 12 times an hour, but were only monitored according to a preset time, thus allowing radon to be monitored continuously in a uranium mine. The counter can be set to monitor each detector for any period of time up to 16.5 Minutes. This allows very low concentrations to be monitored longer to reduce statistical error. There would be no upper limit in radon concentration that could be monitored, but there would be a lower limit of 50 picocuries per liter (pci/l). Each detector was calibrated in the laboratory by the Lucas Flask Method. Multiple samples were taken at two different concentrations, and the correction factor for each detector was determined by a least squares fit of the data. Our agreement at low radon concentrations (300 pci/l) with the two-filter method was within 3 percent. At high concentrations the coefficient of variation ranged between 2.1 and 9.8 percent for the five different detector units.
IH; Report of Investigations
NTIS Accession No.
NTIS: PB 250 739