New Concept for the Variable Flow Rate Andersen Cascade Impactor and Calibration Data

A Multi-laboratory in Vitro Study to Compare Data from Abbreviated and Pharmacopeial Impactor Measurements for Orally Inhaled Products: a Report of the European Aerosol Group (EPAG)

“…The remainder opted to use the ACI under pharmacopeial flow rate conditions. Organization B tested their DPI at 60 L/min with collection stages −1 to 6 in sequence, followed by the back-up filter, in accordance with the recommendations of Nichols for high flow rate testing with this apparatus (14). Organizations C and E undertook their measurements with the flow rate at 28.3 L/min, with the standard stage configuration for pMDI testing (stages 0 to 7 in sequence, followed by the back-up filter).…”

Aerodynamic deposition of combination dry powder inhaler formulations in vitro: A comparison of three impactors

“…Eur., 2004). A modification to the ACI has been proposed (Nichols et al, 1998) to allow an increase in the flow rate to 60 L min −1 by removing stage 7 and adding a new stage (−1). A further modification was also suggested (Nichols, 2000) by removing stages 6 and 7 and adding stages (−2) and (−1) enabling the impactor to be operated at 90 L min −1 .…”

Particle Size Analysis of Aerosols from Medicinal Inhalers

“…Size ranges appropriate to these and other CIs occasionally used for inhaler testing that are based on published calibration data, are summarized in Tables 5-9. Cascade impactors are typically calibrated on a stage-by-stage basis using monodisperse aerosol particles [64][65][66][67][68][69][70][71][72][73][74] that are ideally electrostatically charge equilibrated [73]. The process is both labor intensive and time consuming, so that measurement of stage nozzle diameters (so-called stage mensuration) is currently regarded as an acceptable substitute to verify that impactor performance is maintained with use [12].…”