ACFM ambient cascade impactor

The Andersen low-pressure cascade impactor (LPl) is an adaptor assembly which is used with stages 0 through 7 of an Andersen 1 ACFM ambient cascade impactor (Section 4.1) to extend the range of particle classification below 0.4 pm. Standard aerosol cascade impactors are nor- 

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Analyses of such radioactive aerosols were performed by Yu et al. (1993) at Chin-Shan Nuclear Power Plant, NPP in Taiwan, comprising a 636-MWe boiling water reactor (BWR) that has been in operation since 1977. They used Andersen ambient cascade impactors (1 ACFM normal cascade impactors at an airflow rate of 28.3 1 min ) with a preseparator to discriminate large particles with an aerodynamic diameter greater than 10 pm. For the segregation of smaller size aerosol particles in the accumulation mode, they applied a low-pressure adaptor to the Andersen cascade impactor. At an airflow rate of 3 lmin the effective cutoff aerodynamic diameter of sampled aerosols by the low-pressure Andersen cascade impactor (LPI) was between 0.08 and 35 pm. Fission products including and " La and the ac-... 

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