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 premetered 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.]. NOTE There might be times when a device falls under the scope of this International Standard and that of ISO 27427. The committee envisions that the intended use of the product and the risk assessment of the device will derive which International Standard the manufacturer chooses for design verification of the ADDD. This International Standard outlines the process by which ADDD design verification is to be performed in conjunction with a risk-based device functionality profile of the ADDD with either the medication, a placebo or a representative medication. ISO 27427 outlines the process by which the characterization of the aerodynamic aerosol performance of a nebulizing system for use with a non-specific class of active pharmaceutical ingredient(s) is made.