What is a Good Wearable Medical Alarm Design, Anyway?: Do we really know to design a wearable medical alarm?

Designing alarms for medical equipment may seem easy, but the standards' requirements combined with the nonlinearity of the acoustic transducers, with the difficulties of assessing the acoustic impedance of the transducer chamber, and with criteria such as power consumption and efficiency of the electric to acoustic conversion make the design challenging. We systematically analyze the related problems and discuss design solutions specifically for wearable alarms; examples are shown for an implemented alarm with usual driver. The main focus is on the power efficiency and the sound spectra of these alarms.