Current Approaches to APSD Measurements of OIPs Based on Inertial Impaction - Good Cascade Impactor Practices, AIM and EDA for Orally Inhaled Products - page 49

Fig. 2.23 Trudell Medical International “delay” apparatus coupled to USP/Ph.Eur. induction port
with low-flow five-stage MMI developed for testing inhalation devices intended for use by infants
or small children

Vertical Moving Shutter Plate

VHC

Solenoid

MIC

OMRON
Timer

Reset

MIC Power Solenoid

Control

Fig. 2.24 Schematic diagram of Trudell Medical International “delay” apparatus showing work-
ing components ( From [ 67 ] —used with permission )

elapsed time between MDI actuation and the onset of sampling is achieved by inter-
posing a mechanical shutter housed in a purpose-built adapter that locates on axis
between the VHC and induction port leading to a CI that is operated at a flow rate
appropriate for the intended patient category for the VHC (Fig. 2.24 ).