Today, thermal mass flowmeters are used to measure the flow of gases in a growing range of applications, such as chemical reactions or thermal transfer applications that are difficult for other flowmetering technologies. Some other typical applications of flow sensors can be found in the medical field like, for example, CPAP devices, anesthesia equipment or respiratory devices. This is because thermal mass flowmeters monitor variations in one or more of the thermal characteristics (temperature, thermal conductivity, and/or specific heat) of gaseous media to define the mass flow rate.