Simple Method of Size Estimation of Radioactive Aerosols in Air Monitoring

A new simplified method for particle size estimation of radioactive aerosols was proposed for air monitoring. It does not need any new instruments but a traditional aerosol sampling device with a multistage filter system. The method is based on the particle size dependency of penetration for air filter. Decontamination factor data measured in each filter stage is inversed to a size distribution of aerosols. When air filter for a dust sampler such as Toyo HE-40T is used, the method can be applied for a size estimation of aerosols ranging from 0.2 to 10 m in which ICRP is interested for lung deposition model. In a size measurement of 19BAu aerosols, it was shown that the size distribution estimated by the present method was in a good agreement with the distribution by the existent method using a cascade impactor.