The system is of the type for use by a person and including a handpiece and an imaging device, the handpiece containing a breath alcohol tester and the imaging device being adapted to capture an image including the handpiece when a breath sample is delivered to the handpiece. The improvement includes a sensor arrangement and a computing functionality. The sensor arrangement is adapted to provide information from which an orientation and position of the handpiece can be calculated. The computing functionality is adapted to: generate a calculated orientation and position of the handpiece; and if a face appears in the image, precisely locate the features thereof. The features of the face are located using the calculated orientation and position of the handpiece.