The ERWEKA Type Dosage Unit Sampling App. DUSA-MDI has been designed for the sampling and testing of pressurised Metered Dose Inhalers (MDI's). It is used to perform those tests specified by the relevant compendial standards, namely, "Total Number of Discharges per Container or Inhaler", "Dose Uniformity" and "Dose Uniformity Over the Entire Contents" as well as those tests designed to simulate the performance of the inhaler during actual use.