This International Standard applies to the design, labelling, instructions for use and testing requirements for hand-held single- and multi-use aerosol drug delivery devices (ADDDs) intended to deliver a metered or pre-metered aerosolized medication to or by means of the human respiratory tract (including nasal, oral, tracheal, bronchial and alveolar sites). This International Standard applies to both refillable and disposable devices intended for personal use. This International Standard is intended for device design verification and not for drug product quality assessment. The objective of this International Standard is to verify, by laboratory (in-vitro) testing, that the ADDD design consistently meets the manufacturer's design specification by satisfying a device functionality profile and system verification test both of which are determined from a risk assessment and evaluated in accordance with the instructions for use.This International Standard excludes continuous or semi-continuous aerosolization devices covered in ISO 27427, aerosolization devices which do not emit active pharmaceutical ingredient (API), general purpose aerosolization devices (for use with ventilators) and atomizers. This International Standard does not apply to manufacturers of single parts or components of the ADDDs [e.g. (spray) pumps, valves, containers, etc.].