Abstract: A particle sizing sampling device to separate particles from a gaseous medium according to particle diameter so as to classify the particles which include one or more stages with a housing defining an impaction chamber therein, an impaction plate in the impaction chamber, at least one impaction nozzle which forces a jet of the gaseous medium against the impaction plate to separate those particles above the effective particle cut diameter of the stage of the sampler by jet impaction and at least one exit passage which extends through the impaction plate with an inlet spaced from the impaction plate a distance greater than the distance between the gas jet stream outlet from the impaction nozzle and the impaction plate.

Abstract: A preseparator for connection to the sampling inlet of a particle sizing sampler to preseparate those particles from the gaseous medium with particle diameters above the particle diameter acceptance range of the sampler which is characterized by a housing defining a preseparating chamber therein, an impaction plate dividing the preseparating chamber into two subchambers, a preimpaction nozzle which forces a jet of the gaseous medium against the impaction plate to separate those particles above the particle diameter acceptance range of the sampler by jet impaction and at least one exit passage which extends through the impaction plate with an inlet spaced from the impaction plate a distance greater than the distance between the outlet on the preimpaction nozzle and the impaction plate.