In this article, we summarize the theory and practice of applying both the “effective diameter test” and the “jet-to-plate test” to the question of the suitability for continued use of a cascade impactor. The overall goal is to help users eliminate both Type I and Type II errors when assessing impactor suitability. Perhaps surprisingly, no data other than that already gathered by optical stage mensuration is required to apply both tests, allowing the impactor user community, with no additional measurements, to ensure that impactors in use are aerodynamically equivalent to a new impactor.
A practical method for eliminating type I and type II errors when assessing the suitability for continued use of a cascade impactor
Both effective diameter and jet-to-plate criteria are required but the approach is easy.