An automated radon progeny analysis, data transmittal and computer processing system

A system is described which automatically samples and monitors environmental concentrations of radon and thoron progeny in the air. The detector system has been combined with a data logger and modem to transmit accumulated measurements daily from a remote measurement site to a laboratory computer. Measurements are repeated at thirty-minute intervals and the concentrations are stored on magnetic tape on an HP-85 computer which is part of the Alpha Nuclear-Model 750 radon-thoron progeny analyzer. The instrument must be serviced at weekly intervals to rewind the moving filter tape. Once per day the data logger communicates with the laboratory computer and arranges the transfer of accumulated measurements of 218Po, 214Pb, 214Bi, 216Po, 212Pb and working levels along with counting statistic precision estimates for each measurement. The system has been used to monitor radon-progeny concentrations in two homes in Edgemont, South Dakota. In addition to the radon-thoron progeny monitoring, the data logger is used to measure 15-minute averages of parameters which can influence radon-progeny concentrations. Those parameters, such as air-exchange rates, temperature and barometric pressure, are recorded and transmitted to the laboratory computer during the same daily transfer interval used for the radon-thoron progeny data transfer. Data arrays will be subjected to statistical analysis to determine correlations between parameters